Poping on decel and power???

Hey,

So I got my 10.25:1 piston put in my 97 xr650l, valve job, seals, uni air filter and airbox holes and re-jetted to 55/158 and did the drill/washer mods with the mixture screw about 2 turns out.

The bike has power, but it doesn't seem like it has as much as my 87 600r. It also pops lots on decel.

How do I adjust the mixture screw? I went from 3 - 1.5 turns and doesn't seem to make a difference.

Jet to big?

I can't find much about tuning the carb. Any good links?? It will barely lift the front wheel in second.

Any ideas about the popping?

I think my gearing is 14/43, but I have to double check.

Thanks!!

Dave

As far as the popping, be sure the smog stuff is off. Also, be sure there's now exhaust leak.

I think your jetting is way to lean. With the higher comp piston and uncorking mods you should probably be at 160/165 on the main and maybe even higher on the pilot.

Thanks,

I will try a bigger jet.

You think that the popping could be from the jet too small?

What should I expect for power? Close to my 87 600r?

Thanks again,

Dave

yes jetting with that much more compression sounds like it would be low, poping on decel is typical of lean pilot. 58 should be your next size you should try and 160 minimum i would think for a main. Then see what she does with that.

14/43 is pretty close to stock gearing you may wanna try switching that a bit. If you find a good rear that works well you can use either a 14 or 15 front and switch around for whatever riding your doing. With 14/43 it will be hard to pop 2nd weelies without a little bit of help from some pulling.

Yup popping on decel is a lean condition. Bigger pilot and bump a size or 2 on the main...

Happy Jetting :applause:

I will get ne jets when the store opens again.

I couldn't convince the parts guy to give me a 55s pilot jet. He said it was way too big and would only give up a 52s.

My gearing is 14/45. Not 14/43.

Thanks,

Dave

You stated you already had 55/158. I would be looking for 58/ 160-165. I think there is a 162.

Hey,

So I got my 10.25:1 piston put in my 97 xr650l, valve job, seals, uni air filter and airbox holes and re-jetted to 55/158 and did the drill/washer mods with the mixture screw about 2 turns out.

The bike has power, but it doesn't seem like it has as much as my 87 600r. It also pops lots on decel.

How do I adjust the mixture screw? I went from 3 - 1.5 turns and doesn't seem to make a difference.

Jet to big?

I can't find much about tuning the carb. Any good links?? It will barely lift the front wheel in second.

Any ideas about the popping?

I think my gearing is 14/43, but I have to double check.

Thanks!!

Dave

This link to a sticky in jetting is a HUGE help. Sounds lean. May need 1 step up. 160/58. 14/43 is like stock gearing. Go to 14/45 or 14/46. I run 15/48 and its real good on the highway. Popping a lean condition.

How does it crank over now? Stock cam w/auto-decompressor?

http://www.thumpertalk.com/forum/showthread.php?t=327405

He said it was way too big and would only give up a 52s.

Thanks,

Dave

Jetsrus.com if your parts guy continues to deny. I have no idea why he would.

Jetsrus.com if your parts guy continues to deny. I have no idea why he would.

I think some dealers are too PC and wont sell jets that are richer than stock settings.

He is open again tomorrow so I am going to return the ones he gave mw and get a 55 and 165.

The pilot is 55 and 55s?? That s stand for short?

If so, what one should I try first?

Thanks,

Dave

The jets should cost you about 3-5 bucks a piece. Please get the 58 like people have suggested. It is easier and cheaper to grab a couple of different jets while you are there. I would get the 58, 160, and the 165. I would start with the 58 165 combo. If you are at higher elevation try the 55 160 combo

I'll try that first. 58/165. Is there a 58s?

Thanks

The jets should cost you about 3-5 bucks a piece. Please get the 58 like people have suggested. It is easier and cheaper to grab a couple of different jets while you are there. I would get the 58, 160, and the 165. I would start with the 58 165 combo. If you are at higher elevation try the 55 160 combo

Bum nailed it right on with starting recomendations i think, tell you dealer to give you what you asked for and not to back talk him!! Your the customer and if they told me "NO" i would have asked for the store manager and caused a huge ruckus if they said anything else but "please get the man what he asked for!" But thats me.

Take your ones that you have out so they dont give you a wrong one just for visual referance ya know.

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