Whiskey_Irish Posted April 12, 2010 We have a 2004 CRF80F that hesitates off idle. We are the second owners and was told that it has stock jetting. It has a FMF Powercore exhaust and stock intake. I tried moving the needle to full rich and full lean with what feels to me like the same results. I already cleaned out the carb carefully incase there was a clogged jet or water in there but it's the same after spraying out the carb and blowing air through passages. Any ideas? I would try different jets, but I'd don't know what the stock sizes are to confirm I'm starting with stock sizes. Any help appreciated. My 10 year old wants to ride something fierce. Share this post Link to post Share on other sites
slowxr80 Posted April 12, 2010 Try messing around with the air screw a little and see if that helps. With an exhaust you should take the snorkle out of the airbox and get a 98 main jet, then it will run good. Share this post Link to post Share on other sites
Whiskey_Irish Posted April 12, 2010 I did fiddle with air screw and it did help some, but it the hesitation is still there. It can be lessened slightly but it's still pretty bad. The main jet wouldn't resolve the hesitation issue would it? Duane Share this post Link to post Share on other sites
slowxr80 Posted April 12, 2010 I did fiddle with air screw and it did help some, but it the hesitation is still there. It can be lessened slightly but it's still pretty bad. The main jet wouldn't resolve the hesitation issue would it? Duane Will it hesitate just at 1/4 or 1/2 throttle or is it just when you pin it? I would go up one size on the main jet if it's bogging at full throttle. Share this post Link to post Share on other sites
Whiskey_Irish Posted April 12, 2010 It bogs out and hesitates when you open the throttle with any quickness at all. Once at RPM it doesn't cut out, and if you open the throttle slowly it won't hesitate, only when it's quickly opened. IOt does it on the stand and when it's ridden. Share this post Link to post Share on other sites
slowxr80 Posted April 13, 2010 Ok I would go up one size on the main jet and see what happens. Share this post Link to post Share on other sites
Whiskey_Irish Posted April 13, 2010 Ok I would go up one size on the main jet and see what happens. I'll try it. What size is one up from stock? Share this post Link to post Share on other sites
slowxr80 Posted April 13, 2010 I'll try it. What size is one up from stock? It's a 98. Share this post Link to post Share on other sites
fletchman919 Posted April 13, 2010 It doesn't have an accelerator pump. It will always bog if blipped hard. You have to learn to roll it on. Sucks, but it is what it is. Share this post Link to post Share on other sites
