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XR650L Carb setting with dynojet Xr650L

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Hi, I just installed a dynojet kit and Unifilter foam air filter.  I installed the jet kit exactly as described in their directions.

The bike starts great and runs great but does NOT want to start when it's hot.  Very frustrating.

Im at 3000 feet above sea level and installed the 155 jet and set the needle on the 3rd notch and screwed in the mixture then backed it out 2.5 turns as directed.  I also did a carb soak and clean at that time.

any help would be very much appreciated.

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Run the carburetor out of fuel before shutting it off, or at least down a bit.  Turn the fuel off a few hundred feet before shutting the bike off.  Then when you're ready to start the hot bike, turn the fuel back on as you're hitting the starter button.  I used to have that issue too and that solved my problem.

The bike was fine if I restarted it within a couple of minutes of shutting it off, but if it sat for ten or twenty minutes it was difficult to start.  For some reason I no longer have this issue with mine.  It might have been related to a failing pulse generator or ECU.

You could also try adjusting the mixture screw to 2 turns out to see if that helps when hot.

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Thanks Scott! It started only after I pulled the air box side panel off and it fired up.  That is why I was thinking a mixture issue???

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When you thread the mixture screw OUT what am I changing? Adding more fuel or air? Sorry for the newbie question 

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Screw the mixture screw all the way in and you have no fuel flowing through there at idle.  The more you turn it out, the more fuel it adds.  Other types of carburetors do it the other way.  The pilot jet and the idle mixture screw are the only ones that effect how it starts, assuming you leave the throttle closed.

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It started good and idled good before so I can assume pilot jet is good.  Must be an issue with mixture then.  I'll try 2 turns out on mixture setting maybe.

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1 minute ago, XR650L_Dave said:

Try giving it a small amount of throttle while cranking. Or a lot, or even full.

I forgot about that part.  After cranking a couple of times for five seconds each, I would do it with the throttle wide open for a bit and sometimes that was all I needed.

This whole discussion reminds me of why I am no longer willing to ride a kick start bike.  I can remember a DR350S with a hot engine and kicking the thing for five minutes until giving up.  Then waiting about 20 minutes until it was going to be "happy" again and start.

Of course, now that I think about it, I can remember being at an OHV park the first year I had my XR650L, stopping for 10 minutes up at the top and not being able to get it started.  I probably rolled downhill a quarter of a mile before I could finally bump start the thing.  Thankfully those days are in the past.

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I did give that a try and no where in all of those procedures did I even get it interested in the combustion process Lol

Thank you guys!

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5 minutes ago, Dheintz said:

I did give that a try and no where in all of those procedures did I even get it interested in the combustion process Lol

Thank you guys!

The Wide open throttle reply or the turn gas off reply or the 2 turns out on the Idle/Air mixture screw reply ?

The turn the gas off trick fixed my hot start problems also.

 

Edited by WvChamp

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If its hot push the starter button a crack the throttle just a bit.

It will start.......... Mine is the same way on the stock pilot.

The dyno jet kit does not change the pilot jet......... just 2.5-3 turns out on the fuel screw should do it.......

don't over oil your UNI air filter it will hold twice the oil it actually needs to work and BREATH

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On 6/26/2020 at 9:25 AM, ScottRNelson said:

Screw the mixture screw all the way in and you have no fuel flowing through there at idle.  The more you turn it out, the more fuel it adds.  Other types of carburetors do it the other way.  The pilot jet and the idle mixture screw are the only ones that effect how it starts, assuming you leave the throttle closed.

Scott, one what scale is a quarter torn of that needle? When I'm exploring new settings on that fuel screw should it be a quarter or half turn at a time?? Thank you!

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If the needle still has the tab it's pretty easy to figure out how far you're turning it.  Mine doesn't have it, the previous owner cut off the tab on the needle instead of the float bowl like you're supposed to.  Even with the tab removed, mine has a slot for a screw driver, so it's still reasonably easy to tell how far it has been turned, even when it's installed on the bike.  I've always changed mixture screw adjustments 1/4 turn at a time on any bike I'm fiddling with.

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