Motorized Bicycle Information

8/18/2019 Motorized Bicycle Information

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Motorized Bicycle

Information

Driving

• Before each ride check all nuts, bolts, mounting fasteners and safety equipment.

• Open the fuel valve. When the small lever is parallel to the fuel line, the gas is on. When the

lever is sideways, the valve is off. Remember to always turn the valve off when the bike is

not in use.

• The small lever on the right side of the carburetor is the choke. Lift the choke lever up to start

the bike when the engine is cool to the touch. Keep the choke down when the engine is warm.

The choke should only stay up for a few seconds of riding and should quickly be pushed back down for normal riding.

• Pull in the clutch (left handlebar lever). Pedal up to 5 or 6 miles per hour. Quickly release the

clutch lever while continuing to pedal, pull back the throttle and the engine should start. Push

the choke back down and allow the engine to idle and warm for several seconds before riding

away.

• Once the engine is started, always pull in the clutch lever before coming to a stop to allow the

motorized bicycle to idle. With the engine running, always pedal away from a stop before

releasing the clutch to assist the motor.

•

To stop the engine, push kill switch button and turn off the fuel valve.• During the break-in period (first 2 gallons of gas) keep the speed under 20 mph.

Fuel

• Gas/oil ratio during break-in period: 20:1 After break in period: 16-18:1

• This engine is a 2 cycle design, therefore, a gasoline/oil mixture is necessary. During the

break-in period (1st 2 gallons of fuel) and after, the ratio is kept at 20 parts gasoline to 1 part

oil. Use a good quality MOTORCYCLE SYNTHETIC 2-STROKE OIL. This ratio isachieved by mixing 7-8 ounces of Synthetic 2 stroke oil with 1 gallon of gasoline. I suggest

purchasing a fuel container and pre-mixing in the gas can.

Safety• Always wear a helmet.

• Obey all traffic laws.

• Use head and tail lights when driving at night.

• Drive defensively. Cars may not see you or may not realize how fast you can move.

• Do not drive on pedestrian walkways while using the engine.


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• Wipe up any spilled fuel. Never fuel a hot engine or smoke while fueling. This could result in

sudden fire and personal injury. Move your bike at least 10 feet from any fueling area before

starting it. Never leave the tank fuel cap off after fueling as rain water will contaminate the

fuel and cause engine failure.

• Do not store fuel or your bike with fuel in the tank inside an enclosed living space (i.e. an

apartment). In case of fire, it will cause an explosion.

Legal

MOTORIZED BICYCLE – DEFINITION

A pedal bicycle which has a helper motor, or a

non-pedal bicycle which has a motor, with a

cylinder capacity not exceeding fifty (50) cubic

centimeters, an automatic transmission, and

which is capable of a maximum speed of no

more than thirty (30) miles per hour (mph).

OPERATION OF MOTORIZED BICYCLESUnder Massachusetts law, mopeds fall into the category of

“motorized bicycles”(with or without pedals) and are thereforeregulated by the Registrar of Motor Vehicles. Individuals must

have a valid learner’s permit or driver’s license to operate amotorized bicycle or moped.

Mopeds must have automatic transmissions and cylinder

capacities of no more than 50 cubic centimeters. In addition,

mopeds must meet all federal motor vehicle safety standards

and have maximum speeds of no more than 30 mph. Thefollowing limitations apply:

• Individuals may not operate at speeds greater than 25 mph;

• Individuals may not operate on state highways or limited access

roads with signs prohibiting bicycles;

• Individuals may not operate on off-street recreational paths;

• Individuals may use bicycle lanes along roadways;

• Individuals must use the proper hand signals beforestopping or turning;

• Individuals and their passengers must wear United StatesDepartment of Transportation (US DOT) approved helmets

when operating;• Individuals may not carry passengers while operating on a

permit.

Note: In simple terms, your motorized bicycle must be registered with the RMV. This is the form to

take to the RMV to register: http://www.mass.gov/rmv/forms/20017.pdf

It will cost $40 for a two year registration. For the VIN number, use the bicycle’s serial number

filling in zeros in the extra spaces:

http://www.mass.gov/rmv/forms/20017.pdfhttp://www.mass.gov/rmv/forms/20017.pdf


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When you go to the RMV office, say you want to register a moped (which, by law, it is). Don’t

describe it too carefully or it may confuse them. You don’t need to prove the speed or engine size, no

one will inspect it. You don’t even need to take it with you to the RMV office.

Some RMV offices have been known to ask you to apply for a VIN number. Insist that this is not

necessary. If they will not, simply try another office. Motorized bicycles can be legally registered in

MA and I know many who have done so. Unfortunately, some RMV employees are not wellinformed about the variety of moped builds.When registering, you may be asked for a bill or sale or certificate of origin. I am not a store and

cannot provide this, so just say you bought it off Craig’s List or eBay and don’t have one. I have

never known anyone to be rejected for not having one.

By law, motorized bicycles can only be driven at 25 mph or less. To be registered, they must not be

able to exceed 30 mph. However, sometimes RMV employees will ask if they exceed 25 mph. You

may simply answer ‘no’ or point to the law.

It might also be wise to carry a copy of the registration form with you to prove that your bike is street

legal incase you are pulled over. If you are driving too fast or are not wearing a helmet you may still

be ticketed for these offenses.

You must carry your driver’s license or learners permit while driving your motorized bicycle.

General Maintenance

• Consistently running at full RPM is about the worst thing that can be done an engine long

term. Always running at full throttle does not leave enough time for the oil mixed in the gas

to circulate around the engine and lubricate the cylinder wall and lower engine bearings.

If you are going to run at high RPMs, do a plug check. Pull the spark plug once in a while

and see what color it is. If your plug is tan, white, dry and clean, then you need to either

slow down, not ride for so long, and/or increase the oil/gas ratio. If your plug is black and

moist, then you're doing well. Even better is if a little black drop occasionally falls from the

exhaust tip.

• Check EVERY nut and bolt on your bike for tightness – your bike will have lots ofvibrations. If you find any nuts regularly coming loose, add a drop of Loctite.\

• Keep your bike dry. I’d recommend keeping it in a garage if possible. If you live in an

apartment it may not be wise to keep it inside unless you drain the fuel tank. (See safety

section) If you must store it outside, you can buy a bike cover. A cheaper but less effective

cover would be a plastic drop cloth from a hardware store.

Parts Maintenance

#1. How to Adjust Clutch if signs of slipping or squealing are encountered:

A) Disengage clutch by pulling handle bar clutch lever inward and lock into catch lock.

B) Remove right side engine clutch cover and remove small locking screw on center Clutch Adjust

Nut.

C) Pull clutch arm on left rear engine inward. Back off Clutch Adjust Nut ¼ turn counterclockwise.

D) Release handlebar clutch lever and check for slight 1/16" free-play on engine clutch arm.

E) Readjust Clutch Adjust Nut as required to get required 1/6” clutch arm free play.

F) Tighten Clutch Adjust Nut on clutch plate clockwise until just snug.

G) Then re-install small locking screw in outer edge of Clutch Adjust Nut .


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H) Good idea to place a small gob of grease at the gear mesh area. Use grease sparingly! Then

replace the cover.

I ) Squirt light grade oil down clutch cable sheathing to reduce friction and make for easy lever pull.

#2. Carburetor

After every 5 hours of operation check the adjustment of the mixture screw by rotating screwclockwise until seated and then rotate screw 4½ turns back counterclockwise. Depending on dusty

riding conditions, clean air filter every 5 to 20 hours of operation by removing the filter cover to

access the screen and element. Wash element with a degreasing agent such as Simple Green™ or

Purple Stuff ™. Be sure element is completely dry before re-assembly. IMPORTANT: If engine runs

poorly clean tank shut off value filter.

#3.Spark Plug

Remove spark plug and inspect for excess carbon build up. Clean, re-gap to .028- .034 of an inch if

necessary. Check plug after every 20 hours of operation.

#4.Exhaust systemExcessive periods of low speed operation, idling or leaving fuel petcock in the “on” position during

shut down periods may cause the pipe and muffler to become clogged with unburned fuel.

#5.Chain

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

A) Rolling the bicycle forward to remove slack from the bottom of the chain.

B) Find the center and push downward on the top of chain while measuring the deflection.

C) Tighten chain if deflection is more than ½ inch.

#6.Head Bolts Tighten all fasteners after each 10 hours of operation. Most important to check

Cylinder head bolts : Tighten in a X pattern to 8 to 9 ft/lb. for 48cc 55cc; 12 ft/lb for 70cc 80ccengines using a torque wrench. A two piece cylinder and head design engine requires head bolts be

kept tight.

Important: Check head bolts before each and every long ride, vibration can cause them to loosen and

blow a head gasket. Caution: Do not over torque or head bolts may break off. ( Twisted or broken

head bolts due to over tightening is not covered by warranty. )

#7.Right side gears: Remove cover plate and keep small amount of heavy grease on gear train. Do

not over grease as leaks will occur and also may adversely affect clutch operation. Regular

greasing if required will help reduce gear wear and keep gear train quiet.

#8.Left side drive: Routinely pack grease in the shaft hole behind 10T drive sprocket and also in

cover bushing hole. This will also help deduce noise. Make sure drive sprocket nut remains tight.

#9. Combustion Chamber: If your spark plug is black, dry, and sooty, then it may be time to

clean the combustion chamber. "Decarbonisation" was a common maintenance procedure in the days

when British motorcycles roamed the streets and leather clad rockers owned the roads. You need to

keep a clean environment in the combustion chamber. With high mile heavy use (5,000 miles+), we


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do see a build up of carbon beneath the cylinder head and on the combustion chamber. If the carbon

buildup is thick, this barnacle-like substance can cause a piston seizure if any small piece breaks off

and lodges between the piston and cylinder wall.

To "Decarbonise" an engine, remove the 4 nuts on top of the cylinder head, remove the cylinder head

and metal head gasket. Bring the piston to the top of its stroke. Using sand paper or a soft wire

wheel, remove the carbon from the top of the piston crown and the bottom of the cylinder head. Becareful not to score any of the inner surfaces.

#10. Air Filter: Clean your air filter often to prevent foreign particles from entering the piston

chamber.

Hints

• Vibration is an issue with motorized bicycles. If this becomes a problem for you, remove the

left handlebar grip, then fill the handlebars with sand. For more weight, mix in led fillings or

ball bearings. Be sure the right side is being filled, too. This will increase the weight of the

bike by a few pounds, but should reduce vibrations.

• For an extra boost in horsepower, remove the baffle from the exhaust pipe and then drill 2small holes in the long skinny pipe about an inch and a half from the end closest to the outlet.

This will increase the noise level a tad, but the horse power increase will be dramatic! For

max horse power increase, simple cut the pipe about an inch to 2 inches from the outlet and

then replace, or drill one hole, replace and then ride and see how much noise is increased vs.

power gained. You can then drill another hole to increase the power and, as you do, decide if

you have enough power vs. the increase in noise.

Motorized Bicycle Information

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