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Diagnosis assistance

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Been struggling for a year now getting an 86' XL straightened out. Have it running now, after having pulled the carb a million times, and that's a mega pain.

When I'm off the bike, if I hit the gas, it revs pretty descent through the power band. When I'm on it, cruising down the back road, when I hit the gas it's real sluggish, and takes a minute for things to rev up.

The motor is stock, and I have the XRSonly header and pipe on. Pilot is 65, left main is 128, right main is 125. Location is Upstate, NY.

If anyone has any ideas, I'd love to hear them.

I can't tell if it's drowning in gas, or not getting enough.

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How did you come about choosing the jets you have? I would do the next size up from OE on both carbs pilot included.

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I'm not really sure, i can't remember what ones xrs only sent, so it could have been a shop I had time it down in Georgia. I'll go 1 up from stock on both, thanks for the tip!!

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Everything is stock except exhaust. Believe me, when I say sluggish, I mean "what the &$@$ is going on here" sluggish.
I just ordered a bucket of jets, so I'll tear it down for the 1,000,001 time and retune.

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1 hour ago, XR650L_Dave said:

Timing chain retarded by 1 tooth is a possibility.

That would make it peakier , with more power on top. Advanced would give more bottom end , but it would be a turd on top. I run my cam 6* advanced.

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I've owned the bike for 10 years now, it worked great until I changed the exhaust...I've done nothing to any internal engine parts, unless the timing chain skipped a beat.
But, after I change up the jets again, if it's still funky, I'll look into other possibilities.

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Make sure of the brand of jets you are using to verify size compared to stock.  The numbers are not consistent between manufacturers.  Meaning a 65 is not always the same drill size.  There are some websites that have crossover tables for comparison purposes.

 

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I've owned the bike for 10 years now, it worked great until I changed the exhaust...I've done nothing to any internal engine parts, unless the timing chain skipped a beat.
But, after I change up the jets again, if it's still funky, I'll look into other possibilities.

Are you saying that you have run this jetting for 10 years and it has run well until now? Or is the jetting new?

It is very rich as others have said.

Sent from my SM-G930V using ThumperTalk mobile app

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If the new exhaust is quieter/more restrictive , then that made your current jetting more rich than it was with the other pipe.

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