There are basically 3 ways of doing this depending on the model of the bike…
Changing the ECU
Fitting Inlet and/or Throttle Restrictor
Fitting Inlet and/or Carburettor Restrictor
This is usually done on new bikes using the genuine manufacturers’ kit. The ECU which controls the engine management restricts the fuel injection to cut the power down to 35Kw.
Inlet Manifold Restriction
This is the most popular form of restriction for carburetted models. Our techs remove the carburettors from the inlet manifold and place one restriction blade into each manifold. Sometimes the blades will have an off centre aperture or a small pilot hole. In this instance the aperture or hole needs to be at the lowest point in the relation to the slide. If the blades are oval in shape and match the shape of the inlet manifold these should be fitted between the inlet manifold and cylinder head.
Carburettor restrictions generally consist of tubes, caps or pins that limit the amount of travel of the slides. Our techs remove the carburettor tops and place the restriction tube or cap on top of the diaphragm or in the slide hole. Sometimes the slides will be severely restricted.
With more and more bikes being produced with fuel injection systems this type of restriction is becoming more popular. The basics of the kit are that a device is attached to the side of the injection bodies which stops the throttle cam from opening fully.
Certificate of Compliance
Once the kits fitted you will get a Certificate of Compliance. This is proof that a restriction kit is fitted to your bike and you may need to show this to your insurance company or the police should they ever be requested.