Jump to content
Sign in to follow this  

what needle

Recommended Posts

I have a 06x with a 2005 r cam, 07r head, 08r piston, airbox open and defuser removed. I don't want to start all over on jetting but it has a jd needle (i think) no numbers on it. I want to try a cfr250r needle but dont know if to try a 07 needle because of the 07r head or a 08r needle because of the 08 piston and my jetting is kinda of close to the o8r. I have a 55 leak same as a 08, 185 main, 08r 188 so i'm thinking of the 08 needle, can anyone tell me the number of needle and clip position.

Share this post


Link to post
Share on other sites

I am thinking that the 05R needle should be best. Reason being is if you are using your X carb it is 37MM. The 04-05 R's used the 37 also, 06-09 use a 40MM carb which would change the air flow characteristics thus changing fuel requirements.

Share this post


Link to post
Share on other sites

that is a good point what position was the clip. The reason i was think about the 08 was because most of my jetting was close to it and the 08 had a 55 leeak jet and i didn't want to take the carb all the way off again, that gets to be a pain after a few times. I may keep the one i have because it runs darn good. When warm just touch the start botton and the motor doesn't even sound like it spins just comes to life and there is no bogging at all just thought i may could squeze alittle more out of it.

Share this post


Link to post
Share on other sites

185 or 188 main way too big, even with the jd needle. Forget the R specs unless you have an R, and even with the R's they usually run better jetted down from stock.

Share this post


Link to post
Share on other sites

it has all r parts except carb., i start lean and had alot of bogging. Kept going bigger and bigger on the main and would go bigger if i had one. It ran better everytime i went richer. Now i can't make it bog, after warm up. The motor sounds so much better rich, makes me believe alot of people are running leaner than they think they are. If anybody is having bogging problems try going up on the main, like in the 180's just to see if it helps. A leak jet only helps for a few seconds, a main jet is continous.

Share this post


Link to post
Share on other sites

You really need to look at the back boot on the carb to the airbox. It is really easy to overlook a air leak because it is hard to see all the way around to make sure the boot is not folded over and is secure. Main jets in the 180's just doesn't sound right??

Its sucking air somewhere

Share this post


Link to post
Share on other sites

before i started i spayed carb. cleaner all over both boots and could not find anything. But I didn't check the valve clearance, the intake maybe out, I need to check the valves. I just had seen the jetting for a 08 and a 09 crf250r with a 188 main but larger leak, so i didn't think too much about the 185 main i had in it and it may have alittle more hit with a leaner main but the larger one sure pull good out of the hole in 3rd and up. First and second i can wheelie just by twisting the throttle and no clutch. Absolutele no bog and a good deep exhaut note without the defuser.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×