I just picked up a 04crf with a 88cc big bore kit with a two brothers exhaust. Now the bike starts up at most in 3 kicks in the 30 degree NE weather. When i rev it up to almost full throttle it gets choppy and starts popping flames...normal? does it sound like i need to tune it? Also when im goin from 1st to 2nd then WOT 2nd it gets choppy till i go into 3rd... what you guys think? any comments are appreciated.

 

fiddys are hard to tune3 just rite but your local shop shood be able to adjust it as close to perfect. try to tell them evrythng that is done to it also

 

Why didn't you start it an try it out before you bought it ?

Are you letting it fully warm up ? And are you turning off the choke after you start it .

 

i did...it sounded fine at idle and i revved it up also, just not as high as i did when i finally brought it home. When i test rode it i didnt rip on it..it wasnt mine to beat on yet lolz

 

It could be runnin lean cuz its so cold. You can make adjustments in the carb to help, but one quick way to tell is to pull the choke up half way and see if it gets better, if it does, you need to richen up the carb. You can do that by lowerin the clip on the needle inside the carb slider, were the throttle cable hooks up.

 

If it was spittin flames wouldnt that be consider rich though? either or i will try your advice tomorrow and see how it runs

 

What kind of air filter do you have ? Take it off and see how it runs .

 

my other china bike does this. when i take the air filter off it runs heaps better (almost perfect). when the filter is really clean it goes alright too.

 

put a new plug in it. let it warm up and then pretty much top it out and then shut it off pull the plug and see what color it is. your lookin for a coco brown colored plug. white or really light brown is runin lean. a dark/almost black color is rich. shootin flames is an indication of runin rich. popping while gettin on the throttle means lean.

 

couldnt find the choke..i only found the fuel cut...if the kid upgraded to a 88cckit, would it still have the choke?

 

Its got a brand new K+N filter

 

Some 88 kits do not come with a new carb .

If it is a stock keihin carb , the choke is quite visible . It is a lever on the side of the carb .