Thread: XR650R Thread!
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Old 01-20-2013, 05:24 AM   #15789
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Joined: Aug 2007
Location: Brasov, Romania
Oddometer: 289
Originally Posted by RideFreak View Post
Hanging idle is usally too tight of cables or the valves are too tight. When the cables are too tight the work against each other to hold the slide up for a period of time, when it does come down the other adjustments may be off not letting it idle. Check the freeplay at the grip and make sure it will rotate back and forth a little bit (ensuring they aren't too tight) To check for a cable prob forcebly close the throttle after a rev so the push cable pulls the slide down, if the revs drops down immediately then it's a cable issue.

If the valves are too tight it makes all kinds of wierd running cond including hanging idle and failure to idle. I've seen some pretty worn carbs that had no adverse effect on the running, I'm sure that could happen esp since we can't really see how bad the carb is but it'd be very unusual.

It's not uncommon for the valves to settle in the head a good bit right after a topend job, that would cause them to tighten up relatively quickly. Tight valves = hard starting also. Im thinking that's the issue.

The cable is new and oiled, freeplay is fine, valve clearence is in specs, timing is fine. I started the bike with a makeshift gas tank, without the cable. The bike revs itself up, dosen't respond to air screw movement.
It's driving me crazy.

Went to the garage, took off the carb.
-the throtle valve rotates around it's center(left-right) and the lower gap changes in size
-the valve has a bit of play and can rattle back and forth
-the levers that operate the throtle valve are worn

I will take the carb apart and check the extent of the wear.

achile screwed with this post 01-20-2013 at 05:58 AM
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