Many of you will already know but for some of those who own the older 250cc Japanese motorcycles (particularly the 250cc race replicas) you may not be aware that some of these bikes were factory restricted to meet Japanese power regulations. In 1993 Japan limited motorcycle horsepower to specific amounts relevant to the size of the engine. 250cc's for example were limited to a maximum output of 40hp (30kw). Example those who own a ZXR250C (1993-1998) [Note this may not apply to Malaysian imports from 1993-2004] will only produce a factory output of 40hp, not the 45hp (33kw) found in the A, B and early C model. (Note- This assumes there are no modifications to your motorcycle at all since production and the bike was not un-restricted by importers) So to my question. Does anyone know what was used to restrict the ZXR250 engines?? I have a ZXR250A model.... frame.... my engines and carburetors are off a C model and I'd be interested to know how to check the restriction.
even the 45hp was restricted its too uncanny that all the big 4 makers had inline 4s that produced exactly 45hp problem is noone really knows exactly how they were restricted
to the best of my knowledge, the restriction is in the Carby and the CDI on the C models produced after 1993 , I have also read that the ignition can be retarded and advanced to produce different levels of power : this from Tec Peltier The ZXR250 is most likely restricted by ignition timing. Some have said it has to much others have said it needs more. Now you can adjust the timing by just removing the timing rotor and slotting it to allow you to adjust the timing on your bike if needed. http://www.tecpeltier.com/viewtopic.php?f=16&t=28
i think with modern premiums fuels we could advance the ignition timing fairly far without knocking.... anyone ever tried? someone on the forums who is cashed up should buy a Dyno chassis
I also read somewhere that it has something to do with the CDI (I don't even know what that is?) Also heard that you can tell if your bike's restricted by the speedo. Unrestricted goes up to 240km/h I think and restricted is 180 or 160? May or may not be true.
Capacitor Discharge Ignition http://en.wikipedia.org/wiki/Capacitor_discharge_ignition http://www.motoredbikes.com/showthr...ion-systems-trouble-shooting-how-do-they-work
