06 trx450r__ DG X2 slip-on with just baffle/
velocit intake tube w/ K&N(no air box)
Dynojet kit with 140 main jet, needle on 5th from the top
fuel mixture screw is about 3 turns out.

It bogs when i hit it from Idle to full throttle and it is bogging with the throttle wide open in any gear. breaking up in mid range just a tad.

PLEASE HELP( No one replied to my last post)

 

I don't own a 450 but I have a 400ex and my main jet is a dynojet 165. The stock jet was a 142. As i said i don't own and don't know much about the 450 but that jet sounds small. Pull your spark plug and see what it looks like. white = lean/hot/bad need bigger jet. brown=good black=rich/too much gas

 

Is that a kehin 39 mm. carb? If you have no airbox your main jet should be in the range of a 175-185(depending on elevation). you shouldn't need anything bigger than a 190. Needle jet should probably be at 3rd or 4th setting, and pilot screw should not be adjusted beyond 2.5 to 3 turns out. When I changed muffler, filter, and powerlid, I was trying to dial the carb in in the wintertime-big mistake! I had a 225 jet in, and still had a bog(plug was still white). Now that summer is almost here, I've stepped down to a 190, pilot screw at 2 3/4 out, needle jet clip in 3rd pos., it runs like a champ. Get bigger jets, needle clip back to 3rd or 4th setting and you should be in the ballpark.

 

Forget the dyno jet kit, there junk. Just go to the parts counter and get oem kelihn jets. A 170 main should do you fine. I've tried bumping up the pilot using a 45 and 48 but both were to rich so stock should do you fine. Replace the stock fuel screw with an adjustable one which will make your fine adjustment a breeze. Either use the stock needle or get a CRF450 needle which is adjustable and made for your carb. If you want it to run without any bog, misses, or heisation the key is trash the jet kit and get Kelihn jets. If you want some great info try these sites

http://www.exriders.com/vbb/fo...lay.php?s=&forumid=41


http://450rheadquarters.invisionzone.com/

 

<span class="FTHighlightFont">THanks for the info. I will just put the stock needle back in my carb. and get the jets. I have already ordered my aftermkt idle screw. Thats a must. Thanks again!!</span ft>