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Radio Control: Aerobatics

Author: R. Allison


Edition: Model Aviation - 1997/04
Page Numbers: 83, 84, 85, 87, 89

RADIO CONTROL AEROBATICS 1T Wi II Ls] RU OM have new modeling products anxiously awaited new generation Pattern engines now appearing under hobby shop counters across country development engines such Webra-based UAV Bully 120 two-stroke 05 140 two-stroke YS 1 4OFZ inevitable soon lifting old engine displacement limits FAI F3A 1995 AMA Pattern 1996 became law Ive yet run either new twostrokes Steve Helms Futaba offered chance try out new YS 1 4OFZ advance its introduction easily persuaded After have duty alert readers column possible nifty goodies horizon Yes Pattern fliers got small taste coming attractions couple years ago introduction YS l205C SC powerhouse awesome dimensions consequences squeezing much grunt out mere 1996cc significant handling durability problems Simply put YSl20 SC its original configuration too highly stressed live up Yamada s well-earned reputation producing competition engines almost bullet-proof stupid-proof Modifications carburetion compression ratio yielded later editions SC considerably user-friendly detuning traded some top-end performance better handling solution obvious As Hot Rod Magazine pointed out regular intervals during youth no substitute cubic inches holds true fractions cubic inchor case few cubic centimeters YS 140 FZ bored stroked version late-edition YS l205C Displacement has boosted 23cc accomplished 16mm bore job 32mm 15mm stroke increase 29mm overall bore/stroke ratio remains nearly same engine slightly over-square valve cover air-box concept vented intake valve seat 1 205C has retained rocker arms springs valves components upper valve train shared SC front rear bearings cam bearings same components now-familiar YS regulator valve cover gaskets identical part numbers disc valve wrist pin wrist pin retainers some 0-rings few other minor parts like fuel nipples new 140 needle valve smaller lighter old version throttle also match mounting-bolt pattern needlevalve placement exterior dimensions engine also identical earlier YS 120 engines making new hauler near drop-in replacement difference may cause minor difficulty some installations 4mm about 1/ inch increase cylinder height measured bottom mounting flange exhaust port also raised same amount Other new engine looks roughly same drops old hole runs same mounts headers pipes YS l20s much same what really new about YSl4OFZ Nearly everything counts terms Left The new 11gram 140 magnesium piston left new conrod SC piston right comparison power output handling like crankcase head crank conrod piston liner carb body throttle barrel needle valve assembly camshaft Im engine guru profession didnt complete teardown get out calipers exact comparison some things obvious partially informed eye Obviously bore-and-stroke job required new crankcase crank rod head machined alloy rod much beefier SC version Piston pin crank pin wear problem SC new rod has drilled wrist pin end lubrication double-drilled crank pin end new parts seem capable handling increased load turning some needed longevity boot pesky crankshaft rings April 1997 83 Above YS 140 FZ left YS 1 2OSC right Note rear takeoff return line 140 crankshaft right feature YS 120 AC SC made reassembly such bear gone crankshaft/regulator pressure vent has closed off internally exterior jumper line has fitted front regulator nipple backplate-mounted pressure takeoff behind disc valve location camshaft all-new part drastically different-looking lobe rise sharper lift seems have increased duration decreased flow passages head interior seem relieved smoother needle valve needle valve body have totally redesigned much smaller lighter should save vibration-induced wear throttle barrel has much larger bleed-groove early late SC versions Perhaps significant change new magnesium piston dished top differs slightly shape later SC lower-compression piston new piston weighs mere 11 grams ring compared 16 grams SC/AC pistons front end engine has new drive washer split-collet retainer butted against steel standoff rides front bearing riman arrangement similar YS front seal kit marketed several years ago cure leaky AC front end Last far least new larger 140 lighter previous version YS 120 875 grams 31 oz its published weight 75 grams lighter AC least 20 grams lighter SC Bench-top comparisons fine Snake Drive installed YS 120 mockup Throttle barrel Snake Drive view throttle servo end fitting shown fitting screws retains cable setscrew threads directly throttle servo output shaft informative real engine comparing done airplane bolted onto back end two-meter 10 lb Python 1100 rudely awakened midwinter hibernation refitted experiment readers refit enthusiasts will disappointed learn project consumed total 27 minutesfive spent looking wrench someone borrowed new engine total five minutes run-time received additional tank run through before flying factory settings idle regulator untouched main needle set fairly rich untweaked idle solid smooth 1900 rpm right out box transition smooth instantaneous 16 x 13n APC prop turning 7600-7700 rpm 20% nitro SC turned same prop 7800 rpm 30% nitro seemed much less vibration apparent engine speeds possibly benefit reduced reciprocating mass engine very solid stable through midrange 1 4OFZ hauled 10-lb twometer beast straight up out top box discernible effort transitioned flawlessly generally ran pulled like well-behaved welltuned well-broken YS 2OSC B&P Associates Gives Total Flight Line FREEDOM new electnc starter battery pack cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop ___________________________________________ have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 SCREAMING DIVE ATEACKS AUDIBLE FLIGHT MANEUVERS DrIopdfoRC -if R1S RPM dbI ,kd bNgS No,M, , Uy airspeed Sire deuiI, a ,diil airspeed Udiaaa FOR FREE BROCHURE Air Screamer CM PLUS $475 SHIPPING USA i C products PLUS 5375 SHIPPING USA 6924 E 92nd a OK 74133 DEALERS WELCOME918-492-9435 918-492-9375 LECerelsa RIC SERVICE AT ITS BEST BcONreOt Sales Service Anything Radio Controlled Repairs Updates Custom Modifications Frequency Changes 6 Meter conversions ACE Airtronics Aristo-craft Cirrus EK Futaba Hitec Heathkit Hobby Shack JR Kraft KGL KSE Kline KoPropo Pro-Line RCD Tower Hobbies World Engines & others Calibrated Equipment Quick Turnaround Walk-in daily service 800 am-5OO pm Send Legal sized SAE 1996 Catalog containing lists R/C maintenance hints Discover MCard VISA COD UPS USMAIL FEDEX etc KMI 7420 Seven Mile Rd Northville Michigan 48167 Ph 810-486-4800 Fax 810-486-1603 INSTANT HORSPOWERI wiVh UlVraVhrusV Mufflers Tuned Pipe Performance Hassle Engines Up 1500 RPM Gain over Stock Mufflers Sport & Racing Versions AvailalIe 0525 5F/FX 0532 F/FX 0540 5F/FX/F5R 0546 5F/FX 0561 5F/FX ENYA 40/45/53 CX PEIFOIMANCE SPECIALTIES PO 0X 3146 GARDNERVILLE NV 89410PHONE 702-265-7523 ROSSI 40/45/53 THUNDER TIGER PRO 36/40/46/61 MAGNUM XL 28/32/36/40/45/53 5UIERTIGRE 34/40/45/51/60 MVV54O WERA 28/32/40/505PEED/GT FAX 702-265-7522 April 1997 85 model engine compression Broken rings excessive ring wear excessive piston wear bent valves leaking head gasket can detected thru compression testing Regular testing can determine fasi wear occues allows take corrective action Helps determine condilion used engines buying selling must engine performance modifications EACH GAUGE COMES COMPLETE WITHI GLOWPLUG ADAPTER FOR GLOW ENGINES UPARK PLUG ADAPTER FOR GAS ENGINES EXTRA VALVE CORES SPARE CAPS AND 0-RING except brand new slobbering rich running factory adjustments burning fuel 10% less nitro Toward end second tank revs started pick up engine began come would have flown just sheer fun weather started close test brief apparent new YS 14OFZ monster very friendly huggable sort like Barney attitude Lighter smoother easier handle cubes powerful fewer partscall crazy cant seem find down side predict YS 14OFZ will popular choice now under hobby shop counters will soon going over same counters another new product Im betting will find home Pattern Scale aerobatic model unique patented throttle cable/control system called Snake Drive brainchild retired aircraft mechanic Ralph DeLorio Snake Drive wound flex cable much like small speedometer cable running double Teflon sleeve turn carried -inch aluminum housing available larger gas-burning engines also version fits YS 91 through 140 engines Ive tested latter unit 91-powered model works spectacularly well heart Snake Drive concept idea using rotary output motion servo directly control rotary motion throttle barrel converting linear motion via pushrod cable middle accomplishes several important things gets rid mechanical reverse expo type nonlinear motion servo arm throttle arm bring usual hookup nonlinear motion makes * * Long Engine Life * * Use BRU LINE Air Cleaner Completely Fuel Proof Nylon Rubber Parts Cat No 102 Air Cleaner Coarse $299 Cat No 202 Air Cleaner Fine $299 Replacement Inserts Cat No 104 Pkl2 Inserts Coarse $239 Cat No 204 Pkl2 Inserts Fine $239 FITS MOST ENGINES 25 UP SEE YOUR LOCAL HOBBY DEALER IF UNAVAILABLE LOCALLY SEND TO Bru Line Industries Inc P0 9ox3786 conte Lrs Mchgan4SOl5 Add $2 50 sh pp ng M ch gan es dents add 4% sales tax April 1997 87 EDGE SANDER throttles behave like on-off switches drives us use radio features like throttle expo effort make engine speed actually relate somewhat throttle stick position properly installed absorbs engine shake idle slightest change throttle barrel positionwhich leads rock-solid idle softest mounts An added benefit idle can often set 200-300 rpm lower still stable installed directed almost eliminates friction drag thus extra current draw throttle servo Any features would make worth trying together promote Snake Drive gotta have goodie category first tested Snake Drive surprised throttles engines actually linear nature always blamed poor dump transition carb design carb designs fine problem has always screwy rotary motionllinear motion rotary motion hookups Going through pattern main thing notice throttle changes much smoother todays popular on-again off-again partial throttle flying style much easier execute Snake Drive requires radio end-point adjustments throttle channel beyond no special equipment needed unit will make 900 bend less 3/4 inch measured throttle barrel face throttle arm removed Price YS-sized unit $3495 now order directly Ralph DeLorio 888 742-7737 Webster Hobby Shop 888 546-5159 would expect will able find usual Pattern equipment specialty outlets near future 4I wait longer etoenence awesome thrill paintin sky wIth SLJPER0DRI ri KEOLJ SUPERDRI AVIATIO#J SMOKE OIL prernioro smoke Oil etoditimS WhyOLjR COIIIVENIENT UNITS 0 Supenor intense Smoke 0 Excolinnt persintencein9 1gt$1200 0 COflsistCflt PettofltOflOOCa. 4 191 in9$4800 SUPERDRI ins eneted its rtpototion its 000 Aol, haitI Ask Dnoe PetoOk Dootoon Linsoono OtonO StOcker Ask odostry renutotorers like AMP ond TMEPSII IS-on$0000 ______________________________________Drn,100gnt $27500 ITS TIME YOU TRIED SOME Order Toll-Free Calling 800 545~7 MOW AVIATION ASSOCIATES INC 9707 South 70th Avenue Sddgeview IL 60486 ~~_____ 9999 Fax 706 599-1040 Spa* SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM No MOVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REVOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND WILL RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTH OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32Cc MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDt IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62CC AND Z445 TWIN AND THE U S ENGINES 35 & 41CC WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING April 1997 89 $3995 Pius SHIPPING & HANDLING MANY MORE NCESSORIES PARTS CUSTOM INSTALLATIONI SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTiONSI

Author: R. Allison


Edition: Model Aviation - 1997/04
Page Numbers: 83, 84, 85, 87, 89

RADIO CONTROL AEROBATICS 1T Wi II Ls] RU OM have new modeling products anxiously awaited new generation Pattern engines now appearing under hobby shop counters across country development engines such Webra-based UAV Bully 120 two-stroke 05 140 two-stroke YS 1 4OFZ inevitable soon lifting old engine displacement limits FAI F3A 1995 AMA Pattern 1996 became law Ive yet run either new twostrokes Steve Helms Futaba offered chance try out new YS 1 4OFZ advance its introduction easily persuaded After have duty alert readers column possible nifty goodies horizon Yes Pattern fliers got small taste coming attractions couple years ago introduction YS l205C SC powerhouse awesome dimensions consequences squeezing much grunt out mere 1996cc significant handling durability problems Simply put YSl20 SC its original configuration too highly stressed live up Yamada s well-earned reputation producing competition engines almost bullet-proof stupid-proof Modifications carburetion compression ratio yielded later editions SC considerably user-friendly detuning traded some top-end performance better handling solution obvious As Hot Rod Magazine pointed out regular intervals during youth no substitute cubic inches holds true fractions cubic inchor case few cubic centimeters YS 140 FZ bored stroked version late-edition YS l205C Displacement has boosted 23cc accomplished 16mm bore job 32mm 15mm stroke increase 29mm overall bore/stroke ratio remains nearly same engine slightly over-square valve cover air-box concept vented intake valve seat 1 205C has retained rocker arms springs valves components upper valve train shared SC front rear bearings cam bearings same components now-familiar YS regulator valve cover gaskets identical part numbers disc valve wrist pin wrist pin retainers some 0-rings few other minor parts like fuel nipples new 140 needle valve smaller lighter old version throttle also match mounting-bolt pattern needlevalve placement exterior dimensions engine also identical earlier YS 120 engines making new hauler near drop-in replacement difference may cause minor difficulty some installations 4mm about 1/ inch increase cylinder height measured bottom mounting flange exhaust port also raised same amount Other new engine looks roughly same drops old hole runs same mounts headers pipes YS l20s much same what really new about YSl4OFZ Nearly everything counts terms Left The new 11gram 140 magnesium piston left new conrod SC piston right comparison power output handling like crankcase head crank conrod piston liner carb body throttle barrel needle valve assembly camshaft Im engine guru profession didnt complete teardown get out calipers exact comparison some things obvious partially informed eye Obviously bore-and-stroke job required new crankcase crank rod head machined alloy rod much beefier SC version Piston pin crank pin wear problem SC new rod has drilled wrist pin end lubrication double-drilled crank pin end new parts seem capable handling increased load turning some needed longevity boot pesky crankshaft rings April 1997 83 Above YS 140 FZ left YS 1 2OSC right Note rear takeoff return line 140 crankshaft right feature YS 120 AC SC made reassembly such bear gone crankshaft/regulator pressure vent has closed off internally exterior jumper line has fitted front regulator nipple backplate-mounted pressure takeoff behind disc valve location camshaft all-new part drastically different-looking lobe rise sharper lift seems have increased duration decreased flow passages head interior seem relieved smoother needle valve needle valve body have totally redesigned much smaller lighter should save vibration-induced wear throttle barrel has much larger bleed-groove early late SC versions Perhaps significant change new magnesium piston dished top differs slightly shape later SC lower-compression piston new piston weighs mere 11 grams ring compared 16 grams SC/AC pistons front end engine has new drive washer split-collet retainer butted against steel standoff rides front bearing riman arrangement similar YS front seal kit marketed several years ago cure leaky AC front end Last far least new larger 140 lighter previous version YS 120 875 grams 31 oz its published weight 75 grams lighter AC least 20 grams lighter SC Bench-top comparisons fine Snake Drive installed YS 120 mockup Throttle barrel Snake Drive view throttle servo end fitting shown fitting screws retains cable setscrew threads directly throttle servo output shaft informative real engine comparing done airplane bolted onto back end two-meter 10 lb Python 1100 rudely awakened midwinter hibernation refitted experiment readers refit enthusiasts will disappointed learn project consumed total 27 minutesfive spent looking wrench someone borrowed new engine total five minutes run-time received additional tank run through before flying factory settings idle regulator untouched main needle set fairly rich untweaked idle solid smooth 1900 rpm right out box transition smooth instantaneous 16 x 13n APC prop turning 7600-7700 rpm 20% nitro SC turned same prop 7800 rpm 30% nitro seemed much less vibration apparent engine speeds possibly benefit reduced reciprocating mass engine very solid stable through midrange 1 4OFZ hauled 10-lb twometer beast straight up out top box discernible effort transitioned flawlessly generally ran pulled like well-behaved welltuned well-broken YS 2OSC B&P Associates Gives Total Flight Line FREEDOM new electnc starter battery pack cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop ___________________________________________ have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 SCREAMING DIVE ATEACKS AUDIBLE FLIGHT MANEUVERS DrIopdfoRC -if R1S RPM dbI ,kd bNgS No,M, , Uy airspeed Sire deuiI, a ,diil airspeed Udiaaa FOR FREE BROCHURE Air Screamer CM PLUS $475 SHIPPING USA i C products PLUS 5375 SHIPPING USA 6924 E 92nd a OK 74133 DEALERS WELCOME918-492-9435 918-492-9375 LECerelsa RIC SERVICE AT ITS BEST BcONreOt Sales Service Anything Radio Controlled Repairs Updates Custom Modifications Frequency Changes 6 Meter conversions ACE Airtronics Aristo-craft Cirrus EK Futaba Hitec Heathkit Hobby Shack JR Kraft KGL KSE Kline KoPropo Pro-Line RCD Tower Hobbies World Engines & others Calibrated Equipment Quick Turnaround Walk-in daily service 800 am-5OO pm Send Legal sized SAE 1996 Catalog containing lists R/C maintenance hints Discover MCard VISA COD UPS USMAIL FEDEX etc KMI 7420 Seven Mile Rd Northville Michigan 48167 Ph 810-486-4800 Fax 810-486-1603 INSTANT HORSPOWERI wiVh UlVraVhrusV Mufflers Tuned Pipe Performance Hassle Engines Up 1500 RPM Gain over Stock Mufflers Sport & Racing Versions AvailalIe 0525 5F/FX 0532 F/FX 0540 5F/FX/F5R 0546 5F/FX 0561 5F/FX ENYA 40/45/53 CX PEIFOIMANCE SPECIALTIES PO 0X 3146 GARDNERVILLE NV 89410PHONE 702-265-7523 ROSSI 40/45/53 THUNDER TIGER PRO 36/40/46/61 MAGNUM XL 28/32/36/40/45/53 5UIERTIGRE 34/40/45/51/60 MVV54O WERA 28/32/40/505PEED/GT FAX 702-265-7522 April 1997 85 model engine compression Broken rings excessive ring wear excessive piston wear bent valves leaking head gasket can detected thru compression testing Regular testing can determine fasi wear occues allows take corrective action Helps determine condilion used engines buying selling must engine performance modifications EACH GAUGE COMES COMPLETE WITHI GLOWPLUG ADAPTER FOR GLOW ENGINES UPARK PLUG ADAPTER FOR GAS ENGINES EXTRA VALVE CORES SPARE CAPS AND 0-RING except brand new slobbering rich running factory adjustments burning fuel 10% less nitro Toward end second tank revs started pick up engine began come would have flown just sheer fun weather started close test brief apparent new YS 14OFZ monster very friendly huggable sort like Barney attitude Lighter smoother easier handle cubes powerful fewer partscall crazy cant seem find down side predict YS 14OFZ will popular choice now under hobby shop counters will soon going over same counters another new product Im betting will find home Pattern Scale aerobatic model unique patented throttle cable/control system called Snake Drive brainchild retired aircraft mechanic Ralph DeLorio Snake Drive wound flex cable much like small speedometer cable running double Teflon sleeve turn carried -inch aluminum housing available larger gas-burning engines also version fits YS 91 through 140 engines Ive tested latter unit 91-powered model works spectacularly well heart Snake Drive concept idea using rotary output motion servo directly control rotary motion throttle barrel converting linear motion via pushrod cable middle accomplishes several important things gets rid mechanical reverse expo type nonlinear motion servo arm throttle arm bring usual hookup nonlinear motion makes * * Long Engine Life * * Use BRU LINE Air Cleaner Completely Fuel Proof Nylon Rubber Parts Cat No 102 Air Cleaner Coarse $299 Cat No 202 Air Cleaner Fine $299 Replacement Inserts Cat No 104 Pkl2 Inserts Coarse $239 Cat No 204 Pkl2 Inserts Fine $239 FITS MOST ENGINES 25 UP SEE YOUR LOCAL HOBBY DEALER IF UNAVAILABLE LOCALLY SEND TO Bru Line Industries Inc P0 9ox3786 conte Lrs Mchgan4SOl5 Add $2 50 sh pp ng M ch gan es dents add 4% sales tax April 1997 87 EDGE SANDER throttles behave like on-off switches drives us use radio features like throttle expo effort make engine speed actually relate somewhat throttle stick position properly installed absorbs engine shake idle slightest change throttle barrel positionwhich leads rock-solid idle softest mounts An added benefit idle can often set 200-300 rpm lower still stable installed directed almost eliminates friction drag thus extra current draw throttle servo Any features would make worth trying together promote Snake Drive gotta have goodie category first tested Snake Drive surprised throttles engines actually linear nature always blamed poor dump transition carb design carb designs fine problem has always screwy rotary motionllinear motion rotary motion hookups Going through pattern main thing notice throttle changes much smoother todays popular on-again off-again partial throttle flying style much easier execute Snake Drive requires radio end-point adjustments throttle channel beyond no special equipment needed unit will make 900 bend less 3/4 inch measured throttle barrel face throttle arm removed Price YS-sized unit $3495 now order directly Ralph DeLorio 888 742-7737 Webster Hobby Shop 888 546-5159 would expect will able find usual Pattern equipment specialty outlets near future 4I wait longer etoenence awesome thrill paintin sky wIth SLJPER0DRI ri KEOLJ SUPERDRI AVIATIO#J SMOKE OIL prernioro smoke Oil etoditimS WhyOLjR COIIIVENIENT UNITS 0 Supenor intense Smoke 0 Excolinnt persintencein9 1gt$1200 0 COflsistCflt PettofltOflOOCa. 4 191 in9$4800 SUPERDRI ins eneted its rtpototion its 000 Aol, haitI Ask Dnoe PetoOk Dootoon Linsoono OtonO StOcker Ask odostry renutotorers like AMP ond TMEPSII IS-on$0000 ______________________________________Drn,100gnt $27500 ITS TIME YOU TRIED SOME Order Toll-Free Calling 800 545~7 MOW AVIATION ASSOCIATES INC 9707 South 70th Avenue Sddgeview IL 60486 ~~_____ 9999 Fax 706 599-1040 Spa* SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM No MOVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REVOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND WILL RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTH OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32Cc MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDt IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62CC AND Z445 TWIN AND THE U S ENGINES 35 & 41CC WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING April 1997 89 $3995 Pius SHIPPING & HANDLING MANY MORE NCESSORIES PARTS CUSTOM INSTALLATIONI SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTiONSI

Author: R. Allison


Edition: Model Aviation - 1997/04
Page Numbers: 83, 84, 85, 87, 89

RADIO CONTROL AEROBATICS 1T Wi II Ls] RU OM have new modeling products anxiously awaited new generation Pattern engines now appearing under hobby shop counters across country development engines such Webra-based UAV Bully 120 two-stroke 05 140 two-stroke YS 1 4OFZ inevitable soon lifting old engine displacement limits FAI F3A 1995 AMA Pattern 1996 became law Ive yet run either new twostrokes Steve Helms Futaba offered chance try out new YS 1 4OFZ advance its introduction easily persuaded After have duty alert readers column possible nifty goodies horizon Yes Pattern fliers got small taste coming attractions couple years ago introduction YS l205C SC powerhouse awesome dimensions consequences squeezing much grunt out mere 1996cc significant handling durability problems Simply put YSl20 SC its original configuration too highly stressed live up Yamada s well-earned reputation producing competition engines almost bullet-proof stupid-proof Modifications carburetion compression ratio yielded later editions SC considerably user-friendly detuning traded some top-end performance better handling solution obvious As Hot Rod Magazine pointed out regular intervals during youth no substitute cubic inches holds true fractions cubic inchor case few cubic centimeters YS 140 FZ bored stroked version late-edition YS l205C Displacement has boosted 23cc accomplished 16mm bore job 32mm 15mm stroke increase 29mm overall bore/stroke ratio remains nearly same engine slightly over-square valve cover air-box concept vented intake valve seat 1 205C has retained rocker arms springs valves components upper valve train shared SC front rear bearings cam bearings same components now-familiar YS regulator valve cover gaskets identical part numbers disc valve wrist pin wrist pin retainers some 0-rings few other minor parts like fuel nipples new 140 needle valve smaller lighter old version throttle also match mounting-bolt pattern needlevalve placement exterior dimensions engine also identical earlier YS 120 engines making new hauler near drop-in replacement difference may cause minor difficulty some installations 4mm about 1/ inch increase cylinder height measured bottom mounting flange exhaust port also raised same amount Other new engine looks roughly same drops old hole runs same mounts headers pipes YS l20s much same what really new about YSl4OFZ Nearly everything counts terms Left The new 11gram 140 magnesium piston left new conrod SC piston right comparison power output handling like crankcase head crank conrod piston liner carb body throttle barrel needle valve assembly camshaft Im engine guru profession didnt complete teardown get out calipers exact comparison some things obvious partially informed eye Obviously bore-and-stroke job required new crankcase crank rod head machined alloy rod much beefier SC version Piston pin crank pin wear problem SC new rod has drilled wrist pin end lubrication double-drilled crank pin end new parts seem capable handling increased load turning some needed longevity boot pesky crankshaft rings April 1997 83 Above YS 140 FZ left YS 1 2OSC right Note rear takeoff return line 140 crankshaft right feature YS 120 AC SC made reassembly such bear gone crankshaft/regulator pressure vent has closed off internally exterior jumper line has fitted front regulator nipple backplate-mounted pressure takeoff behind disc valve location camshaft all-new part drastically different-looking lobe rise sharper lift seems have increased duration decreased flow passages head interior seem relieved smoother needle valve needle valve body have totally redesigned much smaller lighter should save vibration-induced wear throttle barrel has much larger bleed-groove early late SC versions Perhaps significant change new magnesium piston dished top differs slightly shape later SC lower-compression piston new piston weighs mere 11 grams ring compared 16 grams SC/AC pistons front end engine has new drive washer split-collet retainer butted against steel standoff rides front bearing riman arrangement similar YS front seal kit marketed several years ago cure leaky AC front end Last far least new larger 140 lighter previous version YS 120 875 grams 31 oz its published weight 75 grams lighter AC least 20 grams lighter SC Bench-top comparisons fine Snake Drive installed YS 120 mockup Throttle barrel Snake Drive view throttle servo end fitting shown fitting screws retains cable setscrew threads directly throttle servo output shaft informative real engine comparing done airplane bolted onto back end two-meter 10 lb Python 1100 rudely awakened midwinter hibernation refitted experiment readers refit enthusiasts will disappointed learn project consumed total 27 minutesfive spent looking wrench someone borrowed new engine total five minutes run-time received additional tank run through before flying factory settings idle regulator untouched main needle set fairly rich untweaked idle solid smooth 1900 rpm right out box transition smooth instantaneous 16 x 13n APC prop turning 7600-7700 rpm 20% nitro SC turned same prop 7800 rpm 30% nitro seemed much less vibration apparent engine speeds possibly benefit reduced reciprocating mass engine very solid stable through midrange 1 4OFZ hauled 10-lb twometer beast straight up out top box discernible effort transitioned flawlessly generally ran pulled like well-behaved welltuned well-broken YS 2OSC B&P Associates Gives Total Flight Line FREEDOM new electnc starter battery pack cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop ___________________________________________ have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 SCREAMING DIVE ATEACKS AUDIBLE FLIGHT MANEUVERS DrIopdfoRC -if R1S RPM dbI ,kd bNgS No,M, , Uy airspeed Sire deuiI, a ,diil airspeed Udiaaa FOR FREE BROCHURE Air Screamer CM PLUS $475 SHIPPING USA i C products PLUS 5375 SHIPPING USA 6924 E 92nd a OK 74133 DEALERS WELCOME918-492-9435 918-492-9375 LECerelsa RIC SERVICE AT ITS BEST BcONreOt Sales Service Anything Radio Controlled Repairs Updates Custom Modifications Frequency Changes 6 Meter conversions ACE Airtronics Aristo-craft Cirrus EK Futaba Hitec Heathkit Hobby Shack JR Kraft KGL KSE Kline KoPropo Pro-Line RCD Tower Hobbies World Engines & others Calibrated Equipment Quick Turnaround Walk-in daily service 800 am-5OO pm Send Legal sized SAE 1996 Catalog containing lists R/C maintenance hints Discover MCard VISA COD UPS USMAIL FEDEX etc KMI 7420 Seven Mile Rd Northville Michigan 48167 Ph 810-486-4800 Fax 810-486-1603 INSTANT HORSPOWERI wiVh UlVraVhrusV Mufflers Tuned Pipe Performance Hassle Engines Up 1500 RPM Gain over Stock Mufflers Sport & Racing Versions AvailalIe 0525 5F/FX 0532 F/FX 0540 5F/FX/F5R 0546 5F/FX 0561 5F/FX ENYA 40/45/53 CX PEIFOIMANCE SPECIALTIES PO 0X 3146 GARDNERVILLE NV 89410PHONE 702-265-7523 ROSSI 40/45/53 THUNDER TIGER PRO 36/40/46/61 MAGNUM XL 28/32/36/40/45/53 5UIERTIGRE 34/40/45/51/60 MVV54O WERA 28/32/40/505PEED/GT FAX 702-265-7522 April 1997 85 model engine compression Broken rings excessive ring wear excessive piston wear bent valves leaking head gasket can detected thru compression testing Regular testing can determine fasi wear occues allows take corrective action Helps determine condilion used engines buying selling must engine performance modifications EACH GAUGE COMES COMPLETE WITHI GLOWPLUG ADAPTER FOR GLOW ENGINES UPARK PLUG ADAPTER FOR GAS ENGINES EXTRA VALVE CORES SPARE CAPS AND 0-RING except brand new slobbering rich running factory adjustments burning fuel 10% less nitro Toward end second tank revs started pick up engine began come would have flown just sheer fun weather started close test brief apparent new YS 14OFZ monster very friendly huggable sort like Barney attitude Lighter smoother easier handle cubes powerful fewer partscall crazy cant seem find down side predict YS 14OFZ will popular choice now under hobby shop counters will soon going over same counters another new product Im betting will find home Pattern Scale aerobatic model unique patented throttle cable/control system called Snake Drive brainchild retired aircraft mechanic Ralph DeLorio Snake Drive wound flex cable much like small speedometer cable running double Teflon sleeve turn carried -inch aluminum housing available larger gas-burning engines also version fits YS 91 through 140 engines Ive tested latter unit 91-powered model works spectacularly well heart Snake Drive concept idea using rotary output motion servo directly control rotary motion throttle barrel converting linear motion via pushrod cable middle accomplishes several important things gets rid mechanical reverse expo type nonlinear motion servo arm throttle arm bring usual hookup nonlinear motion makes * * Long Engine Life * * Use BRU LINE Air Cleaner Completely Fuel Proof Nylon Rubber Parts Cat No 102 Air Cleaner Coarse $299 Cat No 202 Air Cleaner Fine $299 Replacement Inserts Cat No 104 Pkl2 Inserts Coarse $239 Cat No 204 Pkl2 Inserts Fine $239 FITS MOST ENGINES 25 UP SEE YOUR LOCAL HOBBY DEALER IF UNAVAILABLE LOCALLY SEND TO Bru Line Industries Inc P0 9ox3786 conte Lrs Mchgan4SOl5 Add $2 50 sh pp ng M ch gan es dents add 4% sales tax April 1997 87 EDGE SANDER throttles behave like on-off switches drives us use radio features like throttle expo effort make engine speed actually relate somewhat throttle stick position properly installed absorbs engine shake idle slightest change throttle barrel positionwhich leads rock-solid idle softest mounts An added benefit idle can often set 200-300 rpm lower still stable installed directed almost eliminates friction drag thus extra current draw throttle servo Any features would make worth trying together promote Snake Drive gotta have goodie category first tested Snake Drive surprised throttles engines actually linear nature always blamed poor dump transition carb design carb designs fine problem has always screwy rotary motionllinear motion rotary motion hookups Going through pattern main thing notice throttle changes much smoother todays popular on-again off-again partial throttle flying style much easier execute Snake Drive requires radio end-point adjustments throttle channel beyond no special equipment needed unit will make 900 bend less 3/4 inch measured throttle barrel face throttle arm removed Price YS-sized unit $3495 now order directly Ralph DeLorio 888 742-7737 Webster Hobby Shop 888 546-5159 would expect will able find usual Pattern equipment specialty outlets near future 4I wait longer etoenence awesome thrill paintin sky wIth SLJPER0DRI ri KEOLJ SUPERDRI AVIATIO#J SMOKE OIL prernioro smoke Oil etoditimS WhyOLjR COIIIVENIENT UNITS 0 Supenor intense Smoke 0 Excolinnt persintencein9 1gt$1200 0 COflsistCflt PettofltOflOOCa. 4 191 in9$4800 SUPERDRI ins eneted its rtpototion its 000 Aol, haitI Ask Dnoe PetoOk Dootoon Linsoono OtonO StOcker Ask odostry renutotorers like AMP ond TMEPSII IS-on$0000 ______________________________________Drn,100gnt $27500 ITS TIME YOU TRIED SOME Order Toll-Free Calling 800 545~7 MOW AVIATION ASSOCIATES INC 9707 South 70th Avenue Sddgeview IL 60486 ~~_____ 9999 Fax 706 599-1040 Spa* SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM No MOVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REVOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND WILL RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTH OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32Cc MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDt IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62CC AND Z445 TWIN AND THE U S ENGINES 35 & 41CC WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING April 1997 89 $3995 Pius SHIPPING & HANDLING MANY MORE NCESSORIES PARTS CUSTOM INSTALLATIONI SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTiONSI

Author: R. Allison


Edition: Model Aviation - 1997/04
Page Numbers: 83, 84, 85, 87, 89

RADIO CONTROL AEROBATICS 1T Wi II Ls] RU OM have new modeling products anxiously awaited new generation Pattern engines now appearing under hobby shop counters across country development engines such Webra-based UAV Bully 120 two-stroke 05 140 two-stroke YS 1 4OFZ inevitable soon lifting old engine displacement limits FAI F3A 1995 AMA Pattern 1996 became law Ive yet run either new twostrokes Steve Helms Futaba offered chance try out new YS 1 4OFZ advance its introduction easily persuaded After have duty alert readers column possible nifty goodies horizon Yes Pattern fliers got small taste coming attractions couple years ago introduction YS l205C SC powerhouse awesome dimensions consequences squeezing much grunt out mere 1996cc significant handling durability problems Simply put YSl20 SC its original configuration too highly stressed live up Yamada s well-earned reputation producing competition engines almost bullet-proof stupid-proof Modifications carburetion compression ratio yielded later editions SC considerably user-friendly detuning traded some top-end performance better handling solution obvious As Hot Rod Magazine pointed out regular intervals during youth no substitute cubic inches holds true fractions cubic inchor case few cubic centimeters YS 140 FZ bored stroked version late-edition YS l205C Displacement has boosted 23cc accomplished 16mm bore job 32mm 15mm stroke increase 29mm overall bore/stroke ratio remains nearly same engine slightly over-square valve cover air-box concept vented intake valve seat 1 205C has retained rocker arms springs valves components upper valve train shared SC front rear bearings cam bearings same components now-familiar YS regulator valve cover gaskets identical part numbers disc valve wrist pin wrist pin retainers some 0-rings few other minor parts like fuel nipples new 140 needle valve smaller lighter old version throttle also match mounting-bolt pattern needlevalve placement exterior dimensions engine also identical earlier YS 120 engines making new hauler near drop-in replacement difference may cause minor difficulty some installations 4mm about 1/ inch increase cylinder height measured bottom mounting flange exhaust port also raised same amount Other new engine looks roughly same drops old hole runs same mounts headers pipes YS l20s much same what really new about YSl4OFZ Nearly everything counts terms Left The new 11gram 140 magnesium piston left new conrod SC piston right comparison power output handling like crankcase head crank conrod piston liner carb body throttle barrel needle valve assembly camshaft Im engine guru profession didnt complete teardown get out calipers exact comparison some things obvious partially informed eye Obviously bore-and-stroke job required new crankcase crank rod head machined alloy rod much beefier SC version Piston pin crank pin wear problem SC new rod has drilled wrist pin end lubrication double-drilled crank pin end new parts seem capable handling increased load turning some needed longevity boot pesky crankshaft rings April 1997 83 Above YS 140 FZ left YS 1 2OSC right Note rear takeoff return line 140 crankshaft right feature YS 120 AC SC made reassembly such bear gone crankshaft/regulator pressure vent has closed off internally exterior jumper line has fitted front regulator nipple backplate-mounted pressure takeoff behind disc valve location camshaft all-new part drastically different-looking lobe rise sharper lift seems have increased duration decreased flow passages head interior seem relieved smoother needle valve needle valve body have totally redesigned much smaller lighter should save vibration-induced wear throttle barrel has much larger bleed-groove early late SC versions Perhaps significant change new magnesium piston dished top differs slightly shape later SC lower-compression piston new piston weighs mere 11 grams ring compared 16 grams SC/AC pistons front end engine has new drive washer split-collet retainer butted against steel standoff rides front bearing riman arrangement similar YS front seal kit marketed several years ago cure leaky AC front end Last far least new larger 140 lighter previous version YS 120 875 grams 31 oz its published weight 75 grams lighter AC least 20 grams lighter SC Bench-top comparisons fine Snake Drive installed YS 120 mockup Throttle barrel Snake Drive view throttle servo end fitting shown fitting screws retains cable setscrew threads directly throttle servo output shaft informative real engine comparing done airplane bolted onto back end two-meter 10 lb Python 1100 rudely awakened midwinter hibernation refitted experiment readers refit enthusiasts will disappointed learn project consumed total 27 minutesfive spent looking wrench someone borrowed new engine total five minutes run-time received additional tank run through before flying factory settings idle regulator untouched main needle set fairly rich untweaked idle solid smooth 1900 rpm right out box transition smooth instantaneous 16 x 13n APC prop turning 7600-7700 rpm 20% nitro SC turned same prop 7800 rpm 30% nitro seemed much less vibration apparent engine speeds possibly benefit reduced reciprocating mass engine very solid stable through midrange 1 4OFZ hauled 10-lb twometer beast straight up out top box discernible effort transitioned flawlessly generally ran pulled like well-behaved welltuned well-broken YS 2OSC B&P Associates Gives Total Flight Line FREEDOM new electnc starter battery pack cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop ___________________________________________ have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 SCREAMING DIVE ATEACKS AUDIBLE FLIGHT MANEUVERS DrIopdfoRC -if R1S RPM dbI ,kd bNgS No,M, , Uy airspeed Sire deuiI, a ,diil airspeed Udiaaa FOR FREE BROCHURE Air Screamer CM PLUS $475 SHIPPING USA i C products PLUS 5375 SHIPPING USA 6924 E 92nd a OK 74133 DEALERS WELCOME918-492-9435 918-492-9375 LECerelsa RIC SERVICE AT ITS BEST BcONreOt Sales Service Anything Radio Controlled Repairs Updates Custom Modifications Frequency Changes 6 Meter conversions ACE Airtronics Aristo-craft Cirrus EK Futaba Hitec Heathkit Hobby Shack JR Kraft KGL KSE Kline KoPropo Pro-Line RCD Tower Hobbies World Engines & others Calibrated Equipment Quick Turnaround Walk-in daily service 800 am-5OO pm Send Legal sized SAE 1996 Catalog containing lists R/C maintenance hints Discover MCard VISA COD UPS USMAIL FEDEX etc KMI 7420 Seven Mile Rd Northville Michigan 48167 Ph 810-486-4800 Fax 810-486-1603 INSTANT HORSPOWERI wiVh UlVraVhrusV Mufflers Tuned Pipe Performance Hassle Engines Up 1500 RPM Gain over Stock Mufflers Sport & Racing Versions AvailalIe 0525 5F/FX 0532 F/FX 0540 5F/FX/F5R 0546 5F/FX 0561 5F/FX ENYA 40/45/53 CX PEIFOIMANCE SPECIALTIES PO 0X 3146 GARDNERVILLE NV 89410PHONE 702-265-7523 ROSSI 40/45/53 THUNDER TIGER PRO 36/40/46/61 MAGNUM XL 28/32/36/40/45/53 5UIERTIGRE 34/40/45/51/60 MVV54O WERA 28/32/40/505PEED/GT FAX 702-265-7522 April 1997 85 model engine compression Broken rings excessive ring wear excessive piston wear bent valves leaking head gasket can detected thru compression testing Regular testing can determine fasi wear occues allows take corrective action Helps determine condilion used engines buying selling must engine performance modifications EACH GAUGE COMES COMPLETE WITHI GLOWPLUG ADAPTER FOR GLOW ENGINES UPARK PLUG ADAPTER FOR GAS ENGINES EXTRA VALVE CORES SPARE CAPS AND 0-RING except brand new slobbering rich running factory adjustments burning fuel 10% less nitro Toward end second tank revs started pick up engine began come would have flown just sheer fun weather started close test brief apparent new YS 14OFZ monster very friendly huggable sort like Barney attitude Lighter smoother easier handle cubes powerful fewer partscall crazy cant seem find down side predict YS 14OFZ will popular choice now under hobby shop counters will soon going over same counters another new product Im betting will find home Pattern Scale aerobatic model unique patented throttle cable/control system called Snake Drive brainchild retired aircraft mechanic Ralph DeLorio Snake Drive wound flex cable much like small speedometer cable running double Teflon sleeve turn carried -inch aluminum housing available larger gas-burning engines also version fits YS 91 through 140 engines Ive tested latter unit 91-powered model works spectacularly well heart Snake Drive concept idea using rotary output motion servo directly control rotary motion throttle barrel converting linear motion via pushrod cable middle accomplishes several important things gets rid mechanical reverse expo type nonlinear motion servo arm throttle arm bring usual hookup nonlinear motion makes * * Long Engine Life * * Use BRU LINE Air Cleaner Completely Fuel Proof Nylon Rubber Parts Cat No 102 Air Cleaner Coarse $299 Cat No 202 Air Cleaner Fine $299 Replacement Inserts Cat No 104 Pkl2 Inserts Coarse $239 Cat No 204 Pkl2 Inserts Fine $239 FITS MOST ENGINES 25 UP SEE YOUR LOCAL HOBBY DEALER IF UNAVAILABLE LOCALLY SEND TO Bru Line Industries Inc P0 9ox3786 conte Lrs Mchgan4SOl5 Add $2 50 sh pp ng M ch gan es dents add 4% sales tax April 1997 87 EDGE SANDER throttles behave like on-off switches drives us use radio features like throttle expo effort make engine speed actually relate somewhat throttle stick position properly installed absorbs engine shake idle slightest change throttle barrel positionwhich leads rock-solid idle softest mounts An added benefit idle can often set 200-300 rpm lower still stable installed directed almost eliminates friction drag thus extra current draw throttle servo Any features would make worth trying together promote Snake Drive gotta have goodie category first tested Snake Drive surprised throttles engines actually linear nature always blamed poor dump transition carb design carb designs fine problem has always screwy rotary motionllinear motion rotary motion hookups Going through pattern main thing notice throttle changes much smoother todays popular on-again off-again partial throttle flying style much easier execute Snake Drive requires radio end-point adjustments throttle channel beyond no special equipment needed unit will make 900 bend less 3/4 inch measured throttle barrel face throttle arm removed Price YS-sized unit $3495 now order directly Ralph DeLorio 888 742-7737 Webster Hobby Shop 888 546-5159 would expect will able find usual Pattern equipment specialty outlets near future 4I wait longer etoenence awesome thrill paintin sky wIth SLJPER0DRI ri KEOLJ SUPERDRI AVIATIO#J SMOKE OIL prernioro smoke Oil etoditimS WhyOLjR COIIIVENIENT UNITS 0 Supenor intense Smoke 0 Excolinnt persintencein9 1gt$1200 0 COflsistCflt PettofltOflOOCa. 4 191 in9$4800 SUPERDRI ins eneted its rtpototion its 000 Aol, haitI Ask Dnoe PetoOk Dootoon Linsoono OtonO StOcker Ask odostry renutotorers like AMP ond TMEPSII IS-on$0000 ______________________________________Drn,100gnt $27500 ITS TIME YOU TRIED SOME Order Toll-Free Calling 800 545~7 MOW AVIATION ASSOCIATES INC 9707 South 70th Avenue Sddgeview IL 60486 ~~_____ 9999 Fax 706 599-1040 Spa* SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM No MOVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REVOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND WILL RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTH OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32Cc MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDt IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62CC AND Z445 TWIN AND THE U S ENGINES 35 & 41CC WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING April 1997 89 $3995 Pius SHIPPING & HANDLING MANY MORE NCESSORIES PARTS CUSTOM INSTALLATIONI SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTiONSI

Author: R. Allison


Edition: Model Aviation - 1997/04
Page Numbers: 83, 84, 85, 87, 89

RADIO CONTROL AEROBATICS 1T Wi II Ls] RU OM have new modeling products anxiously awaited new generation Pattern engines now appearing under hobby shop counters across country development engines such Webra-based UAV Bully 120 two-stroke 05 140 two-stroke YS 1 4OFZ inevitable soon lifting old engine displacement limits FAI F3A 1995 AMA Pattern 1996 became law Ive yet run either new twostrokes Steve Helms Futaba offered chance try out new YS 1 4OFZ advance its introduction easily persuaded After have duty alert readers column possible nifty goodies horizon Yes Pattern fliers got small taste coming attractions couple years ago introduction YS l205C SC powerhouse awesome dimensions consequences squeezing much grunt out mere 1996cc significant handling durability problems Simply put YSl20 SC its original configuration too highly stressed live up Yamada s well-earned reputation producing competition engines almost bullet-proof stupid-proof Modifications carburetion compression ratio yielded later editions SC considerably user-friendly detuning traded some top-end performance better handling solution obvious As Hot Rod Magazine pointed out regular intervals during youth no substitute cubic inches holds true fractions cubic inchor case few cubic centimeters YS 140 FZ bored stroked version late-edition YS l205C Displacement has boosted 23cc accomplished 16mm bore job 32mm 15mm stroke increase 29mm overall bore/stroke ratio remains nearly same engine slightly over-square valve cover air-box concept vented intake valve seat 1 205C has retained rocker arms springs valves components upper valve train shared SC front rear bearings cam bearings same components now-familiar YS regulator valve cover gaskets identical part numbers disc valve wrist pin wrist pin retainers some 0-rings few other minor parts like fuel nipples new 140 needle valve smaller lighter old version throttle also match mounting-bolt pattern needlevalve placement exterior dimensions engine also identical earlier YS 120 engines making new hauler near drop-in replacement difference may cause minor difficulty some installations 4mm about 1/ inch increase cylinder height measured bottom mounting flange exhaust port also raised same amount Other new engine looks roughly same drops old hole runs same mounts headers pipes YS l20s much same what really new about YSl4OFZ Nearly everything counts terms Left The new 11gram 140 magnesium piston left new conrod SC piston right comparison power output handling like crankcase head crank conrod piston liner carb body throttle barrel needle valve assembly camshaft Im engine guru profession didnt complete teardown get out calipers exact comparison some things obvious partially informed eye Obviously bore-and-stroke job required new crankcase crank rod head machined alloy rod much beefier SC version Piston pin crank pin wear problem SC new rod has drilled wrist pin end lubrication double-drilled crank pin end new parts seem capable handling increased load turning some needed longevity boot pesky crankshaft rings April 1997 83 Above YS 140 FZ left YS 1 2OSC right Note rear takeoff return line 140 crankshaft right feature YS 120 AC SC made reassembly such bear gone crankshaft/regulator pressure vent has closed off internally exterior jumper line has fitted front regulator nipple backplate-mounted pressure takeoff behind disc valve location camshaft all-new part drastically different-looking lobe rise sharper lift seems have increased duration decreased flow passages head interior seem relieved smoother needle valve needle valve body have totally redesigned much smaller lighter should save vibration-induced wear throttle barrel has much larger bleed-groove early late SC versions Perhaps significant change new magnesium piston dished top differs slightly shape later SC lower-compression piston new piston weighs mere 11 grams ring compared 16 grams SC/AC pistons front end engine has new drive washer split-collet retainer butted against steel standoff rides front bearing riman arrangement similar YS front seal kit marketed several years ago cure leaky AC front end Last far least new larger 140 lighter previous version YS 120 875 grams 31 oz its published weight 75 grams lighter AC least 20 grams lighter SC Bench-top comparisons fine Snake Drive installed YS 120 mockup Throttle barrel Snake Drive view throttle servo end fitting shown fitting screws retains cable setscrew threads directly throttle servo output shaft informative real engine comparing done airplane bolted onto back end two-meter 10 lb Python 1100 rudely awakened midwinter hibernation refitted experiment readers refit enthusiasts will disappointed learn project consumed total 27 minutesfive spent looking wrench someone borrowed new engine total five minutes run-time received additional tank run through before flying factory settings idle regulator untouched main needle set fairly rich untweaked idle solid smooth 1900 rpm right out box transition smooth instantaneous 16 x 13n APC prop turning 7600-7700 rpm 20% nitro SC turned same prop 7800 rpm 30% nitro seemed much less vibration apparent engine speeds possibly benefit reduced reciprocating mass engine very solid stable through midrange 1 4OFZ hauled 10-lb twometer beast straight up out top box discernible effort transitioned flawlessly generally ran pulled like well-behaved welltuned well-broken YS 2OSC B&P Associates Gives Total Flight Line FREEDOM new electnc starter battery pack cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop ___________________________________________ have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 SCREAMING DIVE ATEACKS AUDIBLE FLIGHT MANEUVERS DrIopdfoRC -if R1S RPM dbI ,kd bNgS No,M, , Uy airspeed Sire deuiI, a ,diil airspeed Udiaaa FOR FREE BROCHURE Air Screamer CM PLUS $475 SHIPPING USA i C products PLUS 5375 SHIPPING USA 6924 E 92nd a OK 74133 DEALERS WELCOME918-492-9435 918-492-9375 LECerelsa RIC SERVICE AT ITS BEST BcONreOt Sales Service Anything Radio Controlled Repairs Updates Custom Modifications Frequency Changes 6 Meter conversions ACE Airtronics Aristo-craft Cirrus EK Futaba Hitec Heathkit Hobby Shack JR Kraft KGL KSE Kline KoPropo Pro-Line RCD Tower Hobbies World Engines & others Calibrated Equipment Quick Turnaround Walk-in daily service 800 am-5OO pm Send Legal sized SAE 1996 Catalog containing lists R/C maintenance hints Discover MCard VISA COD UPS USMAIL FEDEX etc KMI 7420 Seven Mile Rd Northville Michigan 48167 Ph 810-486-4800 Fax 810-486-1603 INSTANT HORSPOWERI wiVh UlVraVhrusV Mufflers Tuned Pipe Performance Hassle Engines Up 1500 RPM Gain over Stock Mufflers Sport & Racing Versions AvailalIe 0525 5F/FX 0532 F/FX 0540 5F/FX/F5R 0546 5F/FX 0561 5F/FX ENYA 40/45/53 CX PEIFOIMANCE SPECIALTIES PO 0X 3146 GARDNERVILLE NV 89410PHONE 702-265-7523 ROSSI 40/45/53 THUNDER TIGER PRO 36/40/46/61 MAGNUM XL 28/32/36/40/45/53 5UIERTIGRE 34/40/45/51/60 MVV54O WERA 28/32/40/505PEED/GT FAX 702-265-7522 April 1997 85 model engine compression Broken rings excessive ring wear excessive piston wear bent valves leaking head gasket can detected thru compression testing Regular testing can determine fasi wear occues allows take corrective action Helps determine condilion used engines buying selling must engine performance modifications EACH GAUGE COMES COMPLETE WITHI GLOWPLUG ADAPTER FOR GLOW ENGINES UPARK PLUG ADAPTER FOR GAS ENGINES EXTRA VALVE CORES SPARE CAPS AND 0-RING except brand new slobbering rich running factory adjustments burning fuel 10% less nitro Toward end second tank revs started pick up engine began come would have flown just sheer fun weather started close test brief apparent new YS 14OFZ monster very friendly huggable sort like Barney attitude Lighter smoother easier handle cubes powerful fewer partscall crazy cant seem find down side predict YS 14OFZ will popular choice now under hobby shop counters will soon going over same counters another new product Im betting will find home Pattern Scale aerobatic model unique patented throttle cable/control system called Snake Drive brainchild retired aircraft mechanic Ralph DeLorio Snake Drive wound flex cable much like small speedometer cable running double Teflon sleeve turn carried -inch aluminum housing available larger gas-burning engines also version fits YS 91 through 140 engines Ive tested latter unit 91-powered model works spectacularly well heart Snake Drive concept idea using rotary output motion servo directly control rotary motion throttle barrel converting linear motion via pushrod cable middle accomplishes several important things gets rid mechanical reverse expo type nonlinear motion servo arm throttle arm bring usual hookup nonlinear motion makes * * Long Engine Life * * Use BRU LINE Air Cleaner Completely Fuel Proof Nylon Rubber Parts Cat No 102 Air Cleaner Coarse $299 Cat No 202 Air Cleaner Fine $299 Replacement Inserts Cat No 104 Pkl2 Inserts Coarse $239 Cat No 204 Pkl2 Inserts Fine $239 FITS MOST ENGINES 25 UP SEE YOUR LOCAL HOBBY DEALER IF UNAVAILABLE LOCALLY SEND TO Bru Line Industries Inc P0 9ox3786 conte Lrs Mchgan4SOl5 Add $2 50 sh pp ng M ch gan es dents add 4% sales tax April 1997 87 EDGE SANDER throttles behave like on-off switches drives us use radio features like throttle expo effort make engine speed actually relate somewhat throttle stick position properly installed absorbs engine shake idle slightest change throttle barrel positionwhich leads rock-solid idle softest mounts An added benefit idle can often set 200-300 rpm lower still stable installed directed almost eliminates friction drag thus extra current draw throttle servo Any features would make worth trying together promote Snake Drive gotta have goodie category first tested Snake Drive surprised throttles engines actually linear nature always blamed poor dump transition carb design carb designs fine problem has always screwy rotary motionllinear motion rotary motion hookups Going through pattern main thing notice throttle changes much smoother todays popular on-again off-again partial throttle flying style much easier execute Snake Drive requires radio end-point adjustments throttle channel beyond no special equipment needed unit will make 900 bend less 3/4 inch measured throttle barrel face throttle arm removed Price YS-sized unit $3495 now order directly Ralph DeLorio 888 742-7737 Webster Hobby Shop 888 546-5159 would expect will able find usual Pattern equipment specialty outlets near future 4I wait longer etoenence awesome thrill paintin sky wIth SLJPER0DRI ri KEOLJ SUPERDRI AVIATIO#J SMOKE OIL prernioro smoke Oil etoditimS WhyOLjR COIIIVENIENT UNITS 0 Supenor intense Smoke 0 Excolinnt persintencein9 1gt$1200 0 COflsistCflt PettofltOflOOCa. 4 191 in9$4800 SUPERDRI ins eneted its rtpototion its 000 Aol, haitI Ask Dnoe PetoOk Dootoon Linsoono OtonO StOcker Ask odostry renutotorers like AMP ond TMEPSII IS-on$0000 ______________________________________Drn,100gnt $27500 ITS TIME YOU TRIED SOME Order Toll-Free Calling 800 545~7 MOW AVIATION ASSOCIATES INC 9707 South 70th Avenue Sddgeview IL 60486 ~~_____ 9999 Fax 706 599-1040 Spa* SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM No MOVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REVOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND WILL RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTH OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32Cc MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDt IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62CC AND Z445 TWIN AND THE U S ENGINES 35 & 41CC WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING April 1997 89 $3995 Pius SHIPPING & HANDLING MANY MORE NCESSORIES PARTS CUSTOM INSTALLATIONI SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTiONSI

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