Question for you CR125/JD Jet kit owners...

I just picked up my son's 07 125 and immediately put a JD Jet kit in it and I installed it with the blue needle, 2nd clip (slightly richer than the red needle third) to be safe. The bike runs awesome and throttle response is crispt but I have noticed one weird thing. Especially under a load, there is a momentary bog or hesitation at around half or 3/4 throttle. That, I assume would mean it is the needle but I am not sure if it is rich or lean spot because the plug looks perfect. I am in the flat ole Midwest (Indiana).

When your riding it hard on the pipe you really do not notice it but I let someone else ride it (who is fast) without telling him anything and he came back and said it had a throttle position related stumble. Strange. I did send James an e-mail but he has been out of town.

Any thoughts here? This is not a huge deal but if I can get rid of it that would be great. :thumbsup:

i got the advise to put in a 50 pilot jet in with the needle kit and a 420 mainjet, this is suppose to cure this stumble, my cr does this also with jd kit, i havent yet bought the 50 pilot, so i havent tryed it in person.. /Andre

i got the advise to put in a 50 pilot jet in with the needle kit and a 420 mainjet, this is suppose to cure this stumble, my cr does this also with jd kit, i havent yet bought the 50 pilot, so i havent tryed it in person.. /Andre

Hmmm...ok, Thanks. Not sure the pilot would/should have any effect on a 3/4throttle position stumble but I may be wrong. I have not even decided I am gonna touch it at all becasue the bike runs awesome. :thumbsup:

I'm the one that gave tage81 the advise to put in the #50 pilot. I had the same problem with the bog or hesitation with the 32.5 pilot. So, I went up to a 40 and it was still there but I did,nt have the problem with the stock 55.

So, I bought the 45 and 50 put in the 50 and the problem was solved. I live in Nebraska so I ride about the same level your at in Indiana.

Good luck

I'm the one that gave tage81 the advise to put in the #50 pilot. I had the same problem with the bog or hesitation with the 32.5 pilot. So, I went up to a 40 and it was still there but I did,nt have the problem with the stock 55.

So, I bought the 45 and 50 put in the 50 and the problem was solved. I live in Nebraska so I ride about the same level your at in Indiana.

Good luck

Ok thanks for the info. Was your Bog off of idle (or more on the bottom) or was it when transitioning through about 3/4 throttle? Cause the jetting on the bottom end is crisp and clean with no hesitation on mine. :thumbsup:

It was mainly when I shifted from 2nd into 3rd was where it was the worst.

I would try it w/ your other needle, or diff. clip position.

I would try it w/ your other needle, or diff. clip position.

Yeah...I am waiting on JD to get back to me but my next step is probably going to be moving the clip down one. The stumble I have just seems like a small "lean spot". This ireally a very minor issue I am talking about here. The bike runs so much better with the JD jet kit it's not even funny.:worthy:

I will let you know what happens :thumbsup:

Thats awesome, I have an 04CR125 that I tuned the old fashioned way of trying 10 different jetting combos, before I found one I liked, that was not too lean. I wish I had known about jdjetting kits.

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