Bizzy13
XS400 Addict
Mixture screws are the 1st thing you do after any mod to jets. I never touch floats but only last resort. Those mixture screw adjustments are a critically necessary adjustment.
I have a similair problem its back firing out the carbs but I have fixed some of the lean condition.I need to adjust the slide needles but Im reletivly clueless on how this is done given the fact I have to use spacers and dont have notches.Im in need of some advice also.Having gotten the bike running again, it still has the high rev problem and some backfire, with some hesitations. Again with lean mix.
I have a similair problem its back firing out the carbs but I have fixed some of the lean condition.I need to adjust the slide needles but Im reletivly clueless on how this is done given the fact I have to use spacers and dont have notches.Im in need of some advice also.
Start up bike, let choke for 2 minutes, return choke, adjust idle to ca. 150 0rpm. That's all good, bike idles fine. Then I go for a ride and accelerate quickly, up to say 6k rpm and pull in clutch/go in neutral but the idle is now at ca. 4k rpm. However I can adjust the throttle stop so that it returns to 1500 rpm, but when I ride again, same thing happens. All the time, idle fine, ride, idle too high, have to adjust idle...
Check the needles. If they aren't seated properly they will rub on the needle jet and cause the slides to hang-up.
The needles should be perfectly vertical and centered in the needle jet. Some carbs use a nylon washer with a locating pin to center the needle in the slides. If the pin hasn't dropped into it's hole, then the needle will be canted at an angle.
The needles could also be bent. Or the diaphragm could be swollen and hanging up. MikesXS.com should have replacement needles. If the diaphragms are shot, then JBM Industries would be your best bet for replacements.