How to Remove the Part That Limits Speed on a 150CC Scooterby Samuel Hamilton
Though more powerful than their smaller, 50cc brothers, 150cc scooters can still be somewhat sluggish compared to larger motorcycles and automobiles. In addition to the smallness of their engine's output, this diminished speed can be attributed to a small washer found in the scooter's drivetrain or variator system which restricts the top speed of the scooter. Removing this piece is a completely legal procedure which will improve the overall acceleration power and top speed of your 150cc scooter.
Take the kickstand off of your scooter. The kickstand is held onto the side of the scooter with a small pin located near the top of it. Loosen the top of the pin, pull it slightly out and pull the kickstand off of the side of your scooter. This will give you access to your scooter's variator case.
Remove the molded intake case. This is the molded plastic part on the side of the scooter to which your kickstand was attached. On most scooters, this piece is held onto the body of the scooter with three bolts, which can be removed with a socket wrench. Other scooters do not have this piece.
Unscrew the six bolts around the outside of the flat, cylindrical piece that looks like a small gearbox. This is the variator case. It houses the belts which power your rear wheel. Three of the bolts are on the top of the case, three are on the bottom.
Remove the outside of the front pulley wheel inside the variator case with an impact wrench. An impact wrench is an air-powered wrench which spins fast enough to counteract the spinning of the wheel as you attempt to remove the single bolt that holds it in place. If you do not have an impact wrench or access to one, you can secure the front wheel with a strap wrench and use a regular socket wrench. Secure the wheel by wrapping the strap around it and then wedging the handle of the wrench underneath the back pulley wheel.
Pull the small washer from around the front pulley bar upon removing the outside of the front pulley wheel. This washer limits the speed of your 150cc scooter.
Put the front pulley wheel back onto the pulley rod, replace the variator case cover and the intake case, and put the kickstand back on the scooter.
- Though a legal procedure, removing the restricting washer could require you to reregister your scooter, as it will increase its overall top speed.
Items you will need
- Impact wrench
- Socket wrench
- Strap wrench
- "Scooters, Automatic Transmission 50 to 250cc (Hayne's Automotive Repair Manual)"; John Haynes; 2006
- scooter image by dead_account from Fotolia.com