Friction Drive Mounting Instructions For All Engines:
Mounting instruction for the Friction drive Bicycle/Trike Kits, model FDR & FDF. Check out our web site before you start mounting the bike kit if available. You can look at the pictures of several bikes and see the many different options of using the mounting brackets.
Note: All engines mount the same regardless of engine brand or size.
These kits are Very easy to install.
ALL Mitsubishi engines are Two Cycle - oil & gas mix. Break in the engine with a 32 to 1 mix ratio or 4.0 oz of two cycle oil to the gallon of unleaded gas. One gallon is enough to break in the engine. Higher octane unleaded gas works best. After break in use a 40-1 mix ratio or mix 3.2 oz of high grade two cycle oil with one gallon of unleaded gas. Note: Engine & starter position can be changed.
All Tanaka engines are two cycle engines. Break in the engine with a 32 to 1 mix ratio or 4.0 oz of two cycle oil to the gallon of unleaded gas. One gallon is enough to break in the engine. After break in mix at a 50 to 1 ratio or 2.6 oz of high quality two cycle oil to one gallon of unleaded gas. Higher octane unleaded gas works best. Note: Engine & starter position can be changed.
Robin - Subaru Four Cycle engine: FDR-335-1.125 (standard drive roller is 1 - 1/8" OD) Micro Four Stroke: Read and follow manual. You must add SAE 10W-30 oil to the engine. EH035 33.5 cc add 3.33 oz and the EH025 24.5 cc add 2.68 oz. You may need to "level" the engine in order to check the oil level correctly. The stop switch mounted on the engine.
Honda GX25, Honda GX35 & Honda GXH50 are all four cycle engines.
Strip 3/8” of the rubber coating off both ends of the wire. Place the stripped wire Plug the male end into the female end that is on the engine, crimp the ends on the black wire. Test to make sure you have a good connection before riding and that the stop switch stops the engine. The 2nd wire is a ground, but usually is not needed to stop the engine. A very few bikes may require that you run a ground or 2nd wire from the engine to the kill switch mount. To stop the engine you can pull the spark plug wire or lift the "chock" lever and the engine will die. If your stop switch is not working, it's best that you do not ride until the switch is replaced.
Rear mounting: You may need to remove the rear fender or cut a space out so the drive roller will engage the tire without making contact with the fender. You also may need to drill a 1/4" hole in the left lower mounting bracket above the rear axle, most bikes have a 5mm threaded hole. Drilling the hole out will allow you to adjust the tension without using any tools.
Use the 1/4" pin with the 3/8" jam nut (as a spacer only) to hold the bottom part of the rod to the frame of the bike. Use the 1/4" bolt & nylon nut to hold the top part of the bracket in place, using a flat washer on each side.
You can place the angle on either side of the ¼“ black housing, trying to keep as straight as line from the housing to the lower axle mount. You may need to drill a ¼“ hole in the “U” shaped bracket to off set the mounting. The quick release will slide up or down, to engage or disengage the drive roller.
Attach the "U" shaped bracket above the rear wheel, you may be able to use the center brake hole, if the bolt is long enough, if not mount the bracket above the brake. Use the 1/4-20 x 1 - 3/4" bolts to attach the backer plate to the "U" bracket. DO NOT over tighten the bolts or you may bend your frame. Some customers will place a small piece of rubber under the mounting brackets.
A old inner tube works great for this. Check to make sure it is tight enough and still positioned correctly after your test ride. Center the drive roller over the center of the tire, or where most of the “knurled” surface is in contact with the smooth tread tire, then tighten the two "keps" nuts against the black Alum. housing to keep in alignment. Tighten the outside 3/8-16 nylon nuts so it is even with the end of the carriage bolt. You may need to have someone squeeze the “U” bracket together so you can place the 3/8-16 nylon nut on the carriage bolt, or use a clamp.
Front mounting: You will need to drill the 1/4" hole in the 1/8" x 1" x 2" flat bar that is welded to a 3/8-16 coupling nut to match the dia. of the axle on the front of the trike or bike. Some axles are 5/16", 3/8" or 10mm. You may want to use a lock washer, "double nut" , or use lock tight to keep the axle nut from coming off. Most front fender can stay on as long as the drive roller does not contact the fender. Some front forks may require longer bolts that are not included.
Run the throttle cable and the remote stop switch wire along the frame up to the handle bars to the right or left side. Install the throttle lever with hose clamp or twist grip first, then the remote stop switch close to the throttle. This way you can "stop" the engine without moving your hand if needed. Use the nylon ties to hold the cable in place, but do not tighten the nylon ties against the cable & wire too tight, leave enough play so the cable will not bind. Be sure and turn the wheel full left and full right and make sure the throttle cable & wire does not bind. Test with the engine not running and make sure the throttle returns to the idle position. Most kick stands will NOT hold the bike up right.
Install the tension rod as shown in the pictures. When the drive roller is not engaged, the slot will be in the higher position, when engaged, it will be in the lower position. Make sure the drive roller does NOT slip on the smooth tread tire or it will wear it. You can place the engaging rod in many positions, use the best position that your bike requires. A extra engaging rod can be added to the right side if needed or wanted.
Starting the engine: After you have mixed the gas and 2-cycle oil in a gas can, fill the tank, then press the primer bulb several times until you see the fuel go in the clear line.
Lift up the chock lever, make sure the stop switch is in the "ON" position, pull the starter rope while supporting the engine. Make sure your hand is not in contact with the drive roller or any hot places on the engine.
Short fast pulls work best. Do not over pull or pull too hard as you may damage the starter.
After the engine starts, let it warm up for about 20 seconds, then lower the lever down.
Read this section real close. You must use a "smooth tread, street style or slick" type tire tread with all friction drive units. This will allow for a better contact point for the drive roller to contact the tire. Check air pressure in the tires, do not over fill, use the amount stated on the tire. Then apply enough pressure to the tire so the drive roller does not slip when given full throttle. A 1/8” to 3/16” depression is about what you will need depending on the engine size and style of tire. If the drive roller slips, be sure and rotate the tire to a new location and adjust more pressure by turning the coupling nut (down by the axle) counter clockwise two full turns then test again. If you do not have enough pressure on the drive roller, it will slip and wear the tire. If you have too much pressure on the tire the engine will not perform very well. Having the correct pressure and style of tire is most important when using a friction drive kit.
Tires with Kevlar work great. Some customers claim up to 1,400 miles on one tire.
Most of these engines will gain about 27% more power after you have used 4 to 6 full tanks of gas and/or gas/mix.
NOTE: There will / may be a "Noise" when the clutch rotor engages the clutch drum. As you increase your speed the noise will stop. The clutch engaging noise is normal. It is best when starting out that you pedal the bike 3-5 turns and help get moving. The larger the drive roller you have the longer the “clutch noise” will sound.
Ride at a slow safe speed and obey all local city and state laws. Always wear ridding and safety gear. A bright colored flag will help others see you. A speedometer, light and reflectors are a good addition to your bike. Make sure you have good front & rear brakes. In most states & cities there is no age limit, tag, license or insurance required on Motorized bikes and trikes. Be sure and check your local city & state laws for complete details. Ride at your own risk. Watch out for the other drivers. Auto traffic may not see you and pull out in front of you.
Be sure and Lock your bike and engine kit up so no one can steel it.
We also offer different sizes of drive rollers for the engines. The smaller the drive roller the more low end power you have, the larger OD drive rollers have a faster top speed but less low end power.
Drive roller stock sizes: 7/8", 1", 1.125”, 1.25" & 1.50".
Do Not Allow the bike fall over. The starter and or engine may be damaged.
