stevefzr

Hi, I am looking for some advice on a problem with my motorbike.... it has never run correctly and the problem has gone from bad to worse! I bought a 1995 FZR600 a year ago and on the first outing it had a spluttering issue at about 7000 rpm. If you keep the power in it broke through it and then carried on revving okish. I contacted the guy I bought it from and he said "the bike has been sitting for a while so old fuel and/or blockage in the carbs could be the problem". Anyway I lived with the problem for a few hundred miles until one day it went from 4 cylinders to 2 and I crawled to my local bike mechanic. He discovered the the CDi was fried as was one of the ignition coils... so we got some second hand ones on Ebay and the bike worked better but he noticed the 7000 rpm problem and so I decided to get him to look at it while it was in the shop. The first run of attempts: Removed, cleaned and adjusted carbs - Didnt help New leads and plugs - Nope Removed K&Ns, and dyno kit and replaced with original airbox and filter - Problem changed. I took the bike for a run to discover the problem had moved to a bigger spluttering between 5000 and 7000 rpm which is difficult to break through and consistantly bad. Back to the work shop. Compression check - all fine So then the bike when to a mate of the mechanic with a dyno and the bike has been on it 10 times and had ALOT of work done on it (for free incidently) Leak down test - All Good Compression test - All Good Valve and ignition timing Swapped coils, cdi and caps for working ones to test - All Good New plugs again Swapped carbs to another ebay set - No Joy Taken off headers and checked - bit cokey but all good Checked pickups for leakage Valve clearances - All Good The outcome is the dyno guy phoned to say even though there was still a slight issue around 6000 rpm is was a good as they could do and I should try it. It felt better but by no means perfect for about 2 miles and then very bad splutter throughout the rev range though still worse in the 5-7k region. When I pulled up pot 3 is not firing correctly at all - I could touch the down pipe. The bike has gone back to the dyno guy and he is happy to keep investigating the problem. Please can some suggestions be thrown in at this point by anyone who thinks they might know the problem. Please please please Thanks Steve