richard 72 Posted January 2, 2010 Share Posted January 2, 2010 I own a 1987 fz 750 with 28000 km on it the bike is all orginal but has a flat spot in the throtle that makes it really hard to ride. I have spent many hours as well as the local yamaha shop trying to fix this they are telling me that the timing is so high that it happens with all these bikes. sorry i dont buy this does any one have any info I did some reseach on this and some shops say its the choke ciruit that is to blame Link to comment Share on other sites More sharing options...
Speedshop Posted January 2, 2010 Share Posted January 2, 2010 This does sound like a typical 'know nothing' answer you get from dealers. The timing would have to be significantly wrong to cause major flat spots. More often then not these problems are caused by several minor mis-adjustments plus one underlying fault. They all act together to cause confusion however. You need to provide more info, have you rebuilt the carbs? Have you had all the jets out and checked none are blocked? Are the diaphragms in good condition? What new parts have to fitted to them if any? Do they balance up OK and stay that way? Are the valves correctly adjusted? What exhaust is fitted? Have you put a timing light on the bike and checked the timing is as it should be (which would knock out your dealer's theory if it is)? You don't say where in the rev range you get the flat spot. Link to comment Share on other sites More sharing options...
Recommended Posts