www.zxrworld.co.uk

Hey guys -

So got home from work today on my break, old man been working on the bike, we finally got her to start and run but now there is a problem it seems.
As he explained it - it ran beautifully for about two minutes, backfired and now sounds terrible, kinda like a thumper, very chunky sound and now we are very worried. anyone had issues like this before? I asked if it may be running on three cylinders but the sound does not match.

Rebuilt the motor. Timing should be fine, all setup up as the manual stated.
Carb rebuilt - new spark plugs, coils work fine just seems mechanical now.

A worried chris
Cheers

can you get a video up? Id say its probably running on 3 cylinders or less if its lumpy. The other thing to consider, re the carbs set up properly and balanced?

I shall put up a video tomorrow evening after I take a look at it again.

Will check out the carbs again.

To check for which cylinders are firing run the bike for about 10seconds and see which downpipes are getting hot or warm.

Ok all sorted - as I thought it was not that it was not firing on all pistons, something got down into one of the cylinders and bent the one valve stem, lucky for us we had the old head.

Bike runs beautifully.

thanks for the quick replies - really helps