Can anyone please help me. I recently spent a fortune having my engine rebuilt as my mechanic said there was oil on the spark plugs. He checked the compresssion and recommended a rebuild. I had gaskets, valve stem seals etc and spent a load. However it is still not running right. At tick over when when i try to rev it often stalls, throttle response is wooly, i wondered if it might be running too rich? I also keep losing the front left cylinder and when i take out the plug it is black, but smells of petrol? I know i should just take it back to him but i don't want to spend more money if i don't have to. Can anyone help?
Thankyou

Sounds like your mechanic does not know his arse from a hole in the ground..

slightly oily plugs is common when these bikes fail to start..I'd start with checking your carbs and swapping the plugs about a bit.

New plugs is always a good start too..

Are you in the UK? Might be better people to go and see....

Yes i am in Sheffield, can you recommend anywhere?
Thanks

Yes I agree CMSMJ1, this fella rebuild the bike so you are with in your rights to take it back and get it sorted for NO CHARGE ! The prick wanted you to rebuild to fleece you but things are still the same , Grease MONKEY comes to mind

morganRVF wrote:Yes i am in Sheffield, can you recommend anywhere?
Thanks

Really...how convenient! Where abouts? PM me, I'll come give you the benefit of my extremely nerdy NC skills...

Who advised you btw?

CMSMJ1 wrote:

morganRVF wrote:Yes i am in Sheffield, can you recommend anywhere?
Thanks

Really...how convenient! Where abouts? PM me, I'll come give you the benefit of my extremely nerdy NC skills...

Who advised you btw?

I'm confident that CM knows all of this but...

Check for a faulty coil thats breaking down under heat / load / intermittently too. I've seen that before.
The plugs are very fragile and die easily, have you replaced them?

If the coil(s) are ok and plugs are new have a look at the pilot screws / float height.

Is it smoking at all? Mine was rich and burning oil and the combination of these meant a fouled plug and non firing cylinder within minutes.. And you can tell not all cyls are firing from a sluggish throttle response.. If its not smoking then oils not getting into the chambers, so the plugs must be fouling from overly rich fuelling