Cutting out on idle?
 

My 97 748Bip has just developed a funny problem. When starting it from warm, and letting it idle before pulling off (rocker protection measure!), it sometimes just stops. It will restart immediately, but when its having a bad fit, it will do it seversal times before I set off.

When running the bikes fine, it has never cut out at lights etc. It does sometimes pop when pulling from low revs in town etc. I recently replaced and carefully reset the TPS.

It doesnt seem to happen when starting the bike from cold, even in this hot weather.

Anyone else had this problem, or have any ideas?

ah that'll be the....
 

......when you reset the TPS did you also set up the throttle body balance, air bleeds, and the co trimmer? All 4 of these are crucial for the bike to run smoothly. It sounds like it might be running a bit lean, but to be honest if any of the above are out it could cause idling/running problems.

I'm sure if you do a search you'll find more info on the above.

Could be the TPS isn't quite right? What procedure did you use for resetting it?
Mitch is correct that the throttles and idle mixture will need balancing/adjusting to complete the job.

Thanks for the advice.

I will look at the air bleed, idle balance and co trim as you suggest.

i reset the TPS by unscrewing the idle screw until it was clear of the cam, and held the throttles closed with my thumb whilst adjusting the pot. I set the pot to 150mv on the nose using the 5v from the ECU and a test lead plugged into the TPS as shown in the manual, earthing the negative lead to the bike, I checkesd the voltage once the locking screws were tight again. It was a bit fiddly to get right.

Any advice on setting the ait bleeds and idle balance using a flow meter (which is what I have)? Also is it possible to set the co pot without a co meter (which I dont have), Perhaps by setting the voltage to 2.5v at the pot wiper pin?

When you clsoed the throttles, did you back off the balance bar so the front butterfly was closed and not being held off by the rear?
Did you disconnect the throttle cable?
The air bleeds need closing to balance the throttles with a vacuum gauge. After that, you'll need a CO analyser to set the mixture and balnce the cylinder mixture.

Thanks Nelly. I will get stuck in next weekend, and report back!

Well as usual it looks as though Nelly was spot on!

I checked the TPS with the linkage disconnected (It was fine - 149mv), closed the air bleeds and then balanced the carbs on the thumbwheel on the likage, balanced the mixture on the air bleeds, and reset the co using the ECU pot, and its a lot better.

It may just be hesitatiing on pick up from very low speeds, but that may be my paranoia! Ity also seems to run a cbit cooler in towns etc.

Thanks everyone!