Motor Boys

bicycle engine kit installation

Fittinginstructions for 80cc bicycleengines

Please take the time to readthese instructions before commencing your project.

Some mechanical ability is verydesirable to properlyinstall your engine. Some buyers can complete the job in 2 hours whilstothers may take 2 days. It is not important how long it takes - youwill gain great pleasure and satisfaction from doing the job right.Have fun. The easiest installation is performed on the standard v frame26" bike with 25mm round tube frame. It can be mounted to some otherbikes but it best to stick with the standard bike. Some motors comewith a frame adapter plate for fitting to non standard oval or largertube configurations. If time and care is taken with the initialinstallation and ongoing maintenance, you should have many thousands onkilometers of trouble freeoperation.

Vibration is a factor with allsingle cylinderbicycle engines so it is a good idea use a spot of 'Holdtite' or'Locktite' on all screws and nuts when installing the engine. If thehead nuts vibrate loose they will cause the head gasket to blow and ifthe side cover plates come loose it will let water into the magneto andcause damage to your electrical system. Engine mounts can also vibrateloose.

Fitted engine

INSTALLING REARSPROCKET

STEP 1

There are two rear sprocket rubberpackers. Cut only one of them. Cut between the drilled holes.

STEP 2

Place the cut one inside of thespokes.

STEP 3

Place the other packer on theoutside of the spokes.

STEP 4

Thread the nine bolts through thesprocket and usethe half moon backing plates on the inside. Tighten all nine boltsmoving across in a star fashion and a little at a time to allow for aneven pull down. Once the sprocket is tight, spin the wheel and checkthat the sprocket runs true. Deviation can be no more than 1.5mm bothways. Any side-to-side excess deviation can be corrected by spinningthe wheel and then tightening the sprocket where needed in order to getcorrect alignment. Make sure bolts are tight. Notice that concavity orindentation of teeth of the rear sprocket is inward towards spokes.This helps keep the chain closer to the inside of the wheel and spokesand allows for better clearance of the rear stays of the bicycle frame.

STEP 4 COMPLETED

Here is how it looks whencompleted. Nice, tight and true.

MOUNTING ENGINE TO FRAME

STEP 5

Mount the engine into the frame.This is the frontmotor mount. Some bikes have a large diameter lower bar and some needclearance for the air box intake so you need to use the parts providedin the kit. Use spacer provided with the kit. This spacer normallywould require the drilling of a hole in the frame to bolt the centre ofthe spacer through (shown below). I prefer the method shown, which isto pull the studs and replace them with longer ones (threaded rod) thatyou can get at the local hardware store. Then you can use the steelmotor mount clamp that came with the kit and not have to drill a holein your frame. Then cut the excess off. My bike had an ovoid shapedlower bar about 50mm across. I used this method.

Here is how the front motor mountlooks if you haveto use the 3 hole adaptor. Yes, you drill and as you can see it worksperfectly and you may have to get a longer bolt and bend the exhaustpipe some too. To bend the pipe, simply get a vice and use some wood toblock the pipe and then bend it. RAW motors has made special galvanisedU-bolt adaptor assemblies.if you don't want to drill a hole throughyourfronttube.

RAW U-clamp large frame adaptor

STEP 5

Here is step 5 complete with studsnipped and lookinggood!! Notice how well the intake inlets clear. Always mount air intakewith inlets down! Always! If you need to, you can put the air box on agrinder and cut down on the inlet tubes a little to make sure theyclear the frame. If you use the spacer on the front engine mount,usually this is enough to clear. Also, you may need to file down anywater bottle screw mounts if they protrude and are in the way of aengine mount.

FITTING CONTROLS

STEP 6

The new style throttle is fittedto the r/h side ofthe handle bars - before you slip the throttle onto bars you will needto drill a 5mm hole in the handle bar 125mm from the end to locate theplastic throttle location tit. Put a drop of machine oil into the cablesheath whilst you have it apart. Care should be taken with the cablelocation grove - if you are too rough with it, you will break it. Begentle when installing the throttle. The throttle has a kill switchincorporated into it. Earth the kill switch anywhere on bike frameusing the wire with the lug on its end. Attach the remaining killswitch wire to the white wire from the engine. Pressing kill switchwill cut power to the spark plug and stop engine running. If your bikehas twist action gear shifter it may cause problems when fitting yourthrottle. The twist action gear shifter can be replaced with a thumbaction gear shifter available from any bike shop or fromthe RAW.

STEP 7

Mount the clutch lever.

STEP 7 COMPLETE

Here is what the clutch cableconnection should look like at the motor.

The larger spring is a heat shield for the clutch cable:

Standard mounting to 28mmtube.

STEP 8

Screw in the fuel valve filtercombo into the tankand then mount the tank. Tip... Wrap top frame tube with bar wrap wheretank clamps are. Also, if you have cable runs on the top bar that areopen cables, you may need to run them through cable sheath the lengthof the tank in order for them to work once tank is clamped over them.Apply plumber’s tape to thread if leaking.

STEP 9

Mount your coil. Tip...Use 2 highquality cable zipties. Go up and over and around the coil and zip tie it to the frame.Loop one zip tie up and over and also through the holes that wouldnormally have the screws going through them. This is a better methodthan using the screws that come with the kit. You will have a moresolid mount and not break the coil. It is not hard the break the coilears off using the screws. Wire Connections: Blue to Blue and Black ToBlack.

Engine vibration can often causethe HT lead betweenthe black box and plug cap to come loose. If this happens you will haveno spark so twist the HT leads in a clockwise direction at both ends toclose connection.

It is very important to ensure thecover plate on themagneto remains tightly sealed (use 'Holdtite' or 'Locktite' onscrews). If water is allowed to get into the magneto chamber, it willcause the magneto to fuse out. Also seal the wire outlet with siliconor similar sealant to ensure water is not carried into the magneto viathe wires. Silicon sealant and 'Holdtite' is available onthe RAW spareparts page.

Testing resistance on magnetocoil should read:
blue to black = about 340ohms; black to white = 2.3ohms

Special Note:If your spark plug has its crown screwed on. Unscrew it and remove itso that you can put your spark plug cap on. Failure to remove thiscrown can damage or ruin the spark plug cap.

Here is what the idler pulleylooks like installed.Notice the wheel is at the most down position so as the chain getsslack, you simply move the wheel upwards to take out the slack.

STEP 10

Remove the 3 screws from Countershaft side cover andalso remove spark plug. Remove clip from master link of chain and thenthread chain up and over counter shaft sprocket by rotating thesprocket using tool. Having the spark plug removed allows engine to beturned easily to thread chain. Tip... Since you have this cover off,hold clutch arm and rotate cover and pull clutch arm out of cover andthen grease it and rotate it back in. RAW engines are fitted with anextra heavy duty 415 chain so it is a good idea to remove the sharptips from the small drive sprocket with a file or grinder to ensuresmoother travel of the chain over the teeth.

STEP 11

Put some molly grease on the shaftand in the hole.

STEP 12

Cut chain to length and usingmaster link put chainback together. Do not cut chain too short! Install idler pulley. Do notover tighten chain. Install chain guard. Use some tin snips to cutcover at the rear if needed. Use a good zip tie at the rear and theextra long bolt for the counter shaft cover will hold the front.

If you ever need a new chain andcan't buy the 415chain locally, you can buy BMX stunt chain (probably even better than415 heavy) from any good bicycle shop - save the waiting time and saveon the freight costs from Bellingen to you.

STEP 13

Install exhaust pipe. If you needto bend the pipe soit will not hit the frame or bolts, clamp the pipe into wood blocks andbend. Don't bend it too much because you don't want to break it. Don'tbend the exhaust whilst mounted to engine. If you do, you will not bendthe exhaust, you will break the motor! Exhaust pipe is very strong -much stronger than the 2 mounting studs on the motor.

STEP 14

Mount the carburetor. Check theother screwsincluding the brass fuel inlet screw for tightness. Typically they needsome slight turning. Once the carburetor is on and tight, you are readyto connect the tank line to the carburetor. Even though thefuelpetcock has a screen filter, it is porous and allows sediment through.A high quality RAW inline fuel filter with paper element isthe way togo to keep fine particulate out of the carburetor and the engine.

The installation is now completed.Mix your oil withthe petrol before adding to tank. Fuel up the bike and fire it up. Itis recommended to pedal the bike up to about walking pace beforereleasing the clutch lever. Enjoy! Don't get too excited... this is anew motor and you need to take it easy for the first 500 kilometers inaccordance with the run-in procedure. You have to run it in but that isfun too...Enjoy!

NOTE: During run in, keepdrive chain snug.During run in keep the mix ratio at 16:1 for 500 kilometers and keepyour speed down to a maximum of 20kph and do not run your motor forlonger than 30 minute periods.

After running in you can allow the chain a littleslack. Also,keep mix ratio at 20:1 and use a high quality motorbike or lawnmowertwo stroke oil.

FAILURE TO FOLLOW THIS RUN-IN PROCEDUREWILL CAUSE YOUR ENGINE TO SIEZE UP AND WILL VOID ANY WARRANTY CLAIM.

WARNING

Do not operate engine without killswitch installed.It could result in personal injury if an emergency stop is required.The only other way of stopping the engine is by releasing the clutchlever with bike brakes on and engine at slowest idle - this is notrecommended.

MAINTENANCE ROUTINE

1. Clutch:

a) Removeright side cover from engine.

b) Place asmall dab of grease at gear mesh area.

c) Replacecover.

2. Carburetor

Depending on riding conditions, clean air filterevery 5 to 20hours of operation by removing the filter cover to access the screenand element. Wash element with a degreasing agent. Be sure element iscompletely dry before re-assembly.

3. Spark Plug

Remove spark plug and inspect for excess carbonbuild up. Clean,re-gap to .6mm - .7mm if necessary. Check plug after every 20 hours ofoperation. A suitable replacement plug an NGK B6HS; NGK B5HS or BOSCHWR 7AC or Champion equivalent is okay to use. The NGK R7-HS is alsorecommended for better performance and smoother idling.

4. Exhaust system

After 20 hours of operation check exhaust pipe forexcessive oiland carbon build-up. Be sure to use supplied support strap to secureexhaust muffler to a solid anchor point on bike frame or engine.

a) Remove exhaust pipe cap by looseningthe retaining screw.

b) Spray degreaser into baffle rinse anddry.

c) Re-assemble

NOTE: Excessiveperiods of low speed operation,idling or leaving fuel petcock in the “on” positionduring shut downperiods may cause the pipe to become clogged with unburned fuel.

5. Chain

Every time bike is ridden check the tension of thedrive chain by:

a) Rolling to bicycle forward to remove slack fromthe bottom of the chain.

b) Find the center and push downward on the top ofchain while measuring the deflection.

c) Tighten chain if deflection is more than 15mm.

d) Low speed "chain rattle" can be eliminated withthe application of graphite grease to chain.

6. Head Bolts

Tighten all fasteners after each five hours ofoperation. It'smost important to check cylinder head bolts: tighten in a X pattern to12 ft/lb. using a torque wrench. A two piece cylinder and head designengine requires head bolts be kept tight. Important:Check head bolts before each and every ride, vibration can cause themto loosen and blow a head gasket. Caution: Do not over torque or headbolts may break off. Use of a little 'Holdtite' or 'Locktite' isrecommended to keep head nuts secured against vibration.

7. Right side gears

Remove cover plate and apply a small amount of heavygrease on gear train. Do not over greaseas leaks will occur and also may adversely affect clutch operation.Regular greasing if required will help reduce gear wear and keep geartrain quiet.

8. Sealing the magneto coil from water
The magneto coil will fuse if it gets wet. Unfortunately with thedesign of the engine, the wire outlet hole faces forward into theweather and water can get into the magneto if the outlet hole is notproperly sealed. RAW engines will come fitted with a rubbergrummetthat will partially exclude water but you are strongly advised tocompletely seal the hole with silicone jelly or a similar product.Sealant and 'Holdtite' is available from the RAW spare partspage.Regularly check cover plates screws are tight. See image below:
General Information
Obey all traffic regulations.Always wear an approvedhelmet whilst riding. Remember that you are riding a motorized bicycleand other traffic may not be able to see you. Never operate yourmotorized bicycle on a pedestrian thoroughfare or pathway whilst theengine is operating. Never operate your motorized bicycle in an unsafemanner.

Check local and statelaws before riding on streets.

WARNING! ALWAYS wear a helmet whilst riding.

Motorized bicyclestarting and operating instructions

IMPORTANT: PLEASE READ THIS
PETROLAND OIL MIXTURE RATIO
The engineis a 2 stroke design, therefore apetrol/oil mixture is necessary. During the first 500km run-in period,the ratio for engine is 16 parts petrol to 1 part high-grade 2 strokemotorcycle oil (65ml Penrite 2 stroke motor oil to 1 litre of 91 octaneunleaded petrol). After the run-in period, the ratio is increased to 20parts petrol to 1 part oil (50ml Penrite 2 stroke motor oil to 1 litreof 91 octane unleaded petrol).
Be sure to mix fuel and oil before adding to tank - don't addseparately.
Do not exceed 20km/h during run-in period.Speed may be increased to 35km/h after the first 500km.

Use only high grade 2 stroke motorcycle oil toensure proper engine lubrication.

WARNING Remember safety first: Wipe up any spiltfuel. NEVER refuel ahot engine or smoke whilst refueling. This could result in fire andpersonal injury. Always move your motorised bike at least 3 metres fromany refueling area before attempting to start it. Never leave the tankfuel cap off after refueling as rain water could contaminate the fueland cause engine failure.

Open the fuel valve. Small lever pointed down withfuel line is in the open position.
Depress the small round cap plunger (tickle button),to prime carburetor. One or two times is enough.
Lift choke lever to the upward position. This is thesmall lever onthe right side of the carburetor. All the way up the choke is on. Allthe way down the choke is off. Move progressively downward to offposition during engine warm up period.
Pull the handlebar clutch lever inward, to disengagethe engine from the rear wheel.
Pedal up to pedestrian walking speed (down hill ifpossible for first start).
Let out the clutch lever all the way out whilecontinuing to pedal.The result is a direct engine hook up with the rear wheel via chain andsprocket and the engine will now start spinning. Pedal until motorstarts. Accelerate slowly at first.
Twist throttle to increase speed, reverse twistthrottle todecrease speed. To stop, disengage clutch and apply brakes. Toaccelerate, pedal and release clutch whilst opening throttle.
Adjust choke to the smoothest engine running position.
After warm up push choke lever all theway down. If engine races too fast, or too slow, pullclutch lever and lock in the button, stop and adjust engine rpm.
If the rpm needs adjusting, turn the idle adjustscrew (top ofcarburetor) in or out slowly to obtain the proper idle speed of about1400 rpm +/- 100 rpm To correctly run the engine in, do not exceed20kph or 30 minutes of continual running for the first 500klms duringengine run in. Engine will develop more power after runin.
To stop the engine, push kill switch and turn offfuel valve attank. Turning off the fuel will prevent fuel from beingdrained fromtank.
Warning: Never leave the tankgas valve in “open” position when engine is notrunning or the bike is in storage.
After or before each ride check all mountingfasteners, includinghead bolts, axle and brakes. Using 'Holdtite' or 'Locktite' duringinitial installation will stop screws and nuts vibrating loose duringrunning.

Warning: Engine lock up or pistonseizure will occurdue to improper petrol/oil mixture. This is the responsibility of theowner/operator to make sure the petrol and oil is mixed correctly andthe run-in procedure is followed correctly.

Wiring: Black andBlue goes with Black and Blue wire. White wire goeswith Red/Yellow and Green is Ground

Oil 8oz of 2 stroke engine oil to 1 gallon of gas for the first 2tanks orfirst month, then change to 4 oz of oil to 1 gallonof gas for rest ofengine life.

Erox House Boots

Motor Boys

bicycle engine kit installation

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