125cc 2-stroke engines are restricted, because they can produce significantly more than 15hp. 125cc 4-stroke engines tend to be designed to produce only about 15hp. As such, they're already running at full power. Sorry. _____ '10 SV650SF, '83 GS650GT (it lives!), Questionable DIY dash project, 3D Printer project, Lasercutter project Detach the carburetor from the intake valves and remove from the motorcycle so that you can access the intakes of the cylinders. Fit a restrictor ring inside the front cylinder intake, you will have a ring with you that will reduce the amount of speed and air that gets through to the carburetor, therefore slowing down the motorcycle. All of my search term words; Any of my search term words; Find results in Content titles and body; Content titles only 1995 Yamaha TZR 80RR service manual. Be the first to answer Feb 08, 2010 • 1995 Yamaha TZR 250 R. derestricting a 3xv for racing,there are no rules for the track,the more power the better - Yamaha 1995 TZR 250 R question. The speed of your 4-stroke, 50CC scooter is restricted by a small washer found in the scooter's variator system. Detach the kickstart from the variator system. It is attached to the system by a pin that is tightened into place with a small bolt. Loosen the bolt and pull the pin and you can remove the kickstart from the scooter. Undo the two nuts which hold the silencer can together and pull it apart. Here you can visibly see the Yasuni quality which you won't see in any other scooter exhausts. All joints are perfectly matched and sealed with O-rings. On many other exhausts the silencer clamps together against the cylindrical sleeve. You missed a good deal on pistonheads a week or so ago 2002 model went for £400, it needed work but as with any bike especially a 2 stroke budget in for for things like, a new piston, top end gasket kit, check things like chain/sprockets, brake pad and disc wear and tyres. These will add a large chunk to the overall price of your bike if needed. 1.E-bike Tool Kits. The first method of derestricting a bike is by using e-bike tool kits. As time passed and the popularity of e-bikes increased, many bike enthusiasts complained about the set speed limits and the need for them to be higher. These concerns were brought to the e-bike manufacturers, who started introducing tool kits to help the Instructions for Making Your 50cc Scooter Faster: Start by locating the kickstand on the side of your scooter. Remove the pin that attaches the kickstand to the scooters body. This is easy to do by loosening the bolt and removing the kickstand pin. Next, you’ll want to find the variator system. You won't get much speed out of a 50cc. 2 realistic options: a big bore kit upping ot to 70cc or another scootie that's at least 150cc. They'll only muster another 4-5 mph at best by only removing the variator shims. To get an extra 15 mph is going to require a BBK, clutch kit, carb, the works. T0Ceoc.