by dickfaber » Tue Oct 25, 2011 6:16 am
how many k's are on the carbies; and have they ever run without air filters?
the carbies on gpx and zzr 250's are almost consumables.
the butterfly valves on the throttle plates can and do float around, wearing an oval where there should be a round at the throttle plate, and chewing out the throttle shft bore. this causes an almost untunable engine. symptoms like high idle, then no idle, then idle hang, then no idle then no rev as the a/f mixture is changed everytime the throttle is moved.easy to check, hold up to the light, there should be an even gap all the way 'round, or if the idle stop screw has been taken out, no gap (no light) all the way round). snap the throttle a coupla times and check again. if not, carbies are rooted; get bran-new-second-hand ones. check them as well.
and dont bother trying to get fcr keihin's, yes they do make some that small, but not in pairs and it will cost more than the bike!
experiance of this? rebuilt at least 5 gpx250's and 2 zzr 250's
I am a bilingual illiterate; i can't read or write in two different languages