My dads mate called round today to see the car. He was playin around with the loom when he noticed we dont hav an EXUP?? Anyone know wat this is, and do we need it to make the engine run??
Cheers

It's a valve that adjusts the exhaust flow Without it there may be a power lull at about 3k revs but it shoudn't affect you driving as I can't see 3Krevs being used much in a BEC.

most people ditch it IIRC, I seem to remember its to do with making the bike conform to certain countries noise level regulations

If you ditch the exup the tacho displays an error code from the cdi unit.
You can either put up with this or make a circuit to fool the cdi into thinking exup is there & working. There's an example in www.biketransplant (sommat like that)
Bob C

I bought an EXUP servo off ebay for £25, which is now mounted under the dash. No fault codes here then!

Yeah keep the servo dump the valve.

Cheers every1

Have a read of this, and follow the links within the thread. I have this info stored in my 'Favorites' for when I finally get my R1 engine...