Why does my XR650 back fire

Last time I rode my XR650R was around 10 months ago (knee injury). Now if I get it started when I let off on the gas it starts to back fire. Another thing is I can't seem to get it to idle right. When I start it up I move the choke up but it soon starts to rev really high so I turn the screw next to the choke until it stops revving high but now when I move the choke to the middle position the bike turns off.

I dumped out all the old gas but that didn't seem to make much difference.

Any suggestions or input will be greatly appreciated.

:confused:

Last time I rode my XR650R was around 10 months ago (knee injury). Now if I get it started when I let off on the gas it starts to back fire. Another thing is I can't seem to get it to idle right. When I start it up I move the choke up but it soon starts to rev really high so I turn the screw next to the choke until it stops revving high but now when I move the choke to the middle position the bike turns off.

I dumped out all the old gas but that didn't seem to make much difference.

Any suggestions or input will be greatly appreciated.

:confused:

sounds like a plugged pilot circuit. lean running at low throttle settings. if it sat for 10 mths. no doubt about it. pull the carb and clean all jets/passage ways.

Never did this before you accident when you rode it alot?

I agree, if it ran fine 10 months ago, but sat all this time, a good carb cleaning probably is your answer. If you have not done so already, now would be a good time to check for proper jetting, needle, positioning of needle seat, etc. for your riding area. :confused:

consider daves mods or a djet kit at this time.

Its a 650R no daves mods

Its a 650R no daves mods

do em any way!

Thanks for all the good input. Yes the bike ran fine before, and it did sit for 10 months. I'll clean the carb out and try it again.

:confused:

sounds like a plugged pilot circuit. lean running at low throttle settings. if it sat for 10 mths. no doubt about it. pull the carb and clean all jets/passage ways.

I have a few questions sinse this is the first time I've done this. I followed the instructions for uncorking the XR650R from Bob Naumann. I removed the carb and sprayed carb. cleaner in any opening I could see and I moved the slide up and down while sparying cleaner. I didn't disassemble anything from the inside (I didn't want to make it worse) No needles were replaced since my bike was already uncorked by previous owner.

When I put it back together it started fairly quick but it still does some back firing. Do you think I still need to clean it a little better? do I need to remove anything located inside of the carb for cleaning?

Thanks and hope to hear from you soon, I really want to ride his thing.

I have a few questions sinse this is the first time I've done this. I followed the instructions for uncorking the XR650R from Bob Naumann. I removed the carb and sprayed carb. cleaner in any opening I could see and I moved the slide up and down while sparying cleaner. I didn't disassemble anything from the inside (I didn't want to make it worse) No needles were replaced since my bike was already uncorked by previous owner.

When I put it back together it started fairly quick but it still does some back firing. Do you think I still need to clean it a little better? do I need to remove anything located inside of the carb for cleaning?

Thanks and hope to hear from you soon, I really want to ride his thing.

http://www.xr650r.us/fiche/

I was told my bike was "uncorked" by the previous owner, but I checked everything to be sure, jets, needle, etc. and found the jetting and needle were incorrect based on Bob's guidelines. I would check everything to be sure, and if the jetting is correct, while they are out clean them well. If something small is wedged in a jet, it may be hard to clean out by just spraying carb cleaner inside the carb. Check out the link above if you are not familar with the stock carb. Its not hard to do, just take your time. I did everything with the carb on the bike, but it is easier to do with the carb off the bike. Good luck! :crazy:

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