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07 CRF70 Jet/Needle help

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I have an 07 CRF70 that I have done the filter pod modificaiton by cutting the extension tube off and I have drilled a couple of holes in the end of the exaust per some instructions on a thread here at TT.

I have recently had some problems getting the bike to idle consistently. I am wondering if I should try and rejet the bike at all or get a needle from an older carb that is adjustable. I do have a unifilter that I can put in as well with the stock pod that I cut.

It is not that the bike wont run or start, it just seems to only idle if I turn it up significantly but as soon as I turn it down even 1/8 of a turn it dies. But the idle that I set to keep it running well is too fast as the bike will move forward if in gear and no throttle is applied.

Any suggestions? Jetting, needle, air screw change with an older carb?

Thanks.

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Idle issues are usually fixed by the air screw, assuming the carb is clean. The needle has more effect at about 1/4 throttle and up. Try fattening up the idle with the mixture screw.

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I did the same mod basicly, however my 70 cuts out when the throttle hits half way. Would moving the needle up a notch fix it?

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It might. Give it a try and see. It seems like a pain to do, but after you do it once or twice, it's not so hard.

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I have an 07 CRF70 that I have done the filter pod modificaiton by cutting the extension tube off and I have drilled a couple of holes in the end of the exaust per some instructions on a thread here at TT.

I have recently had some problems getting the bike to idle consistently. I am wondering if I should try and rejet the bike at all or get a needle from an older carb that is adjustable. I do have a unifilter that I can put in as well with the stock pod that I cut.

It is not that the bike wont run or start, it just seems to only idle if I turn it up significantly but as soon as I turn it down even 1/8 of a turn it dies. But the idle that I set to keep it running well is too fast as the bike will move forward if in gear and no throttle is applied.

Any suggestions? Jetting, needle, air screw change with an older carb?

Thanks.

My 2004 CRF50R was doing the same thing...wouldn't idle but would start & run. Adjusting the valves to .0004 seems to have corrected the problem. Check you valves as well as other suggestions in your thread.

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Adjusting the valves to .0004 seems to have corrected the problem.

There are one too many 0's in there and without the extra 0 it's a little looser than the recommended .002 in. Looser (within reason) is better than too tight.

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There are one too many 0's in there and without the extra 0 it's a little looser than the recommended .002 in. Looser (within reason) is better than too tight.

0.004 was where I set my CRF50R valves...big fingers & trifocals have a tendency to add an extra "0" sometimes.

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...big fingers & trifocals have a tendency to add an extra "0" sometimes.

Now we know the truth. I was thinking moonshine might have been a factor but didn't want to say anything initially.

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Here is what I have done and still need some help.

I pulled the carb apart to make sure the jets were the correct size. I am at 1800 feet above sea level.

Slow Jet: 35

Main Jet: 98

Needle: Set at the 3rd slot from the top (back to stock, it was at the 2nd slot from the top)

Pilot Screw set to stock: out 2 3/8 turns

Now the bike starts fine and idles. Not sure if it is right or not. But I am not sure I have the Throttle Stop Screw set right. Where should the stock/starting position be for the Throttle Stop Screw? I I have not adjusted the pilot screw at all from the 2 3/8 setting.

Any help on initial set up and settings for the throttle stop screw and what to adjust first would be a great help.

Thanks.

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Here is what I have done and still need some help.

I pulled the carb apart to make sure the jets were the correct size. I am at 1800 feet above sea level.

Slow Jet: 35

Main Jet: 98

Needle: Set at the 3rd slot from the top (back to stock, it was at the 2nd slot from the top)

Pilot Screw set to stock: out 2 3/8 turns

Now the bike starts fine and idles. Not sure if it is right or not. But I am not sure I have the Throttle Stop Screw set right. Where should the stock/starting position be for the Throttle Stop Screw? I I have not adjusted the pilot screw at all from the 2 3/8 setting.

Any help on initial set up and settings for the throttle stop screw and what to adjust first would be a great help.

Thanks.

Ummmm...stock main for a 2007 CRF70 is #62 and the pilot is #38, with an opened up air filter you may be able to go up to a #65 and/or shim the needle with one or two small washers. If you do indeed have a #98 main, it is way waaaay too big. #98 main and #35 pilot is what is in a CRF100.

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Ummmm...stock main for a 2007 CRF70 is #62 and the pilot is #38, with an opened up air filter you may be able to go up to a #65 and/or shim the needle with one or two small washers. If you do indeed have a #98 main, it is way waaaay too big. #98 main and #35 pilot is what is in a CRF100.

My bad, I wrote down the settings to my crf100. You are correct. I haven't had a chance to mess with my CRF70. I will have some time in the next week or two. I will report back then.

Thanks.

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My bad, I wrote down the settings to my crf100. You are correct. I haven't had a chance to mess with my CRF70. I will have some time in the next week or two. I will report back then.

Thanks.

Hahaha, good luck, let us know how you make out.

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