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XR650R high idle when hot

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After getting to know my new bike the more I ride it, I am noticing that the idle seems to randomly climb when the engine is hot and I'm in slow sections in the woods or in traffic a little while. What's strange is that it doesn't do it all the time. The bike is stock still...corked with stock jetting and stuff. A couple quick stabs of the throttle will bring it back down automatically occasionally but I sometimes have to manually turn down the idle screw to get her back to a normal RPM. Any suggestions? Thanks!

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Can you manually reduce it with the idle speed adjustment screw when it happens?  That's the easiest way to know whether it's a mechanical issue (worn or dirtly linkage, slide, etc.) or a varying fuel/air mix issue (worn or damaged idle mix screw, incorrect jetting, etc.).

Edited by Hollerhead
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yes i can manually turn down the idle with the brass screw...when i do that however, it makes the idle too low when its not in that "hanging high idle" state. 

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23 minutes ago, mjf6866 said:

yes i can manually turn down the idle with the brass screw...when i do that however, it makes the idle too low when its not in that "hanging high idle" state. 

Uh oh...that's not the idle speed screw.  You're changing the idle mixture. 

It's a tricky thing to get correct on those carbs.  It's definitely not something you (should) need to adjust often.  Do you have a service manual to help you through the details of that mixture setting?

Edited by Hollerhead

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18 minutes ago, Hollerhead said:

Uh oh...that's not the idle speed screw.  You're changing the idle mixture. 

It's a tricky thing to get correct on those carbs.  It's definitely not something you (should) need to adjust often.  Do you have a service manual to help you through the details of that mixture setting?

ahh ok, the one i am turning can be done by hand and it hangs down right near/above the choke lever...and yes, i do have the manual...would probably help if i looked at it :)

Edited by mjf6866

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21 minutes ago, mjf6866 said:

ahh ok, the one i am turning can be done by hand and it hangs down right near/above the choke lever...and yes, i do have the manual...would probably help if i looked at it :)

Then nope, that screw you're adjusting would be the idle speed screw.  The idle mixture, or pilot, screw is accessed from the other side. 

It sounds like you may need an adjustment to the pilot or a jet size check.  Going to back stock sizes is always a good bet if changes have been made.  

I had a hanging idle and found the top cover seal had been reversed creating a small air leak.  It was intermittent as well.  You may find something similar if the adjustment doesn't solve the problem.

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22 hours ago, Hollerhead said:

Then nope, that screw you're adjusting would be the idle speed screw.  The idle mixture, or pilot, screw is accessed from the other side. 

It sounds like you may need an adjustment to the pilot or a jet size check.  Going to back stock sizes is always a good bet if changes have been made.  

I had a hanging idle and found the top cover seal had been reversed creating a small air leak.  It was intermittent as well.  You may find something similar if the adjustment doesn't solve the problem.

ok gotcha...the bike is completely stock still.  stock jetting and still "corked"

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UPDATE:  just in case anyone is following this thread in hopes to find a solution for any similar issues, i may have found it in my case.  The pilot air screw (the one accessed from the right side of the bike) was only turned 1 and 1/2 turns out from full closed.  I read in the manual that is the California version setting and everythinge else should be 2 turns out.  i turned mine 1/2 turn out more to make it 2 full turns from stop and that seems to have fixed my problem.  i've only got two rides in since doing that, but so far so good.  the hanging idle after it gets hot seems to have vanished.  it even seems to have a little more pep now.  that might be in my head though lol.

I will update if anything changes, but thanks for the help!

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