06 yz250f bottom end sucks

[avoidthedog]

hi i bought a 06 yz250f a few months ago and the bottom end power is aweful. its like riding a two stroke. if i ride a gear high i bog out and if i ride a gear low it justs blows through the midrange and just starts bouncing off the rev limiter! i think im exagarating a little but its pretty bad. its pretty much stock, is this how all the 06s are? im thinking of getting a pipe to fix it since my old 02 yz250f had a full fmf system and it ripped. im not concerned about overall hp gains i just want low to midrange power

[desert-rat660]

ya i would try a pipe i heared DRD makes some good ones.

if that doesnt work get a 450:thumbsup:

[desert-rat660]

check the jetting also

[avoidthedog]

the jetting "seems" ok. it doesnt crack or bog or nothing when i rev it. lol a 450 is a little too much for me to handle im only 115lbs. im actually thinking of getting a weapon mx pipe but i dunno if i trust the company. they sent me a sponsorship offer so i could get their pipe for like 300 bucks. its a 102db system so im sure it offers power

[Hempstead]

ive heard weapon mx...is pathetic and may even lose power over stokc

[desert-rat660]

i would go with DRD

[avoidthedog]

wow how the hell do you lose power over stock? the dr.d pipe looks awesome i looked on motosport.com they want 500 for it. thats a good deal but about $100 out of my price range

[patcap]

what do you mean about two stroke like bottom end power ,the 2t's ive had have always had lots of bottom?

[avoidthedog]

meh... like a 85cc two stroke

[desert-rat660]

have u looked on thumpertalk for the pipe

[avoidthedog]

its $550 on here i think

[desert-rat660]

i would save my money for a decent reputable pipe. u dont want to throw a couple hundred dollars away

[williamsmotowerx]

Something's wrong with it. I have a '06 test bike here that's all stock except for jetting and it runs really good.

Get a needle from an '08 and use it in your carb... helps out a ton.

[avoidthedog]

wow ill have to try that. i noticed the bog is even worse when i go wop

[dirtflea]

Play with your gearing as well, you might want to go a tooth or two bigger in the rear. The needle will make a big difference as the tapper is different. Most Yamaha's benifit from changing the taper. Pehaps you can PM "Burned", he is really good with jetting and needles.

[avoidthedog]

Play with your gearing as well, you might want to go a tooth or two bigger in the rear. The needle will make a big difference as the tapper is different. Most Yamaha's benifit from changing the taper. Pehaps you can PM "Burned", he is really good with jetting and needles.

'ok thanks for the info =) i dunno about going up teeth, i dont want it to wind out even quicker, than i gotta shift even quicker to keep away from bouncing off the rev limiter

[oldnbold]

"dog, I know what you mean about the 2ST feel as my 07 had the same feel. Below a certain rpm it had nothing, then once it hit the rpm it would take off. I cured it with jetting.

In my case the pilot was too fat. I leaned it out 1 to a 40PJ but then it had a lean bog when whacking the throttle. I cured that with a 40LJ and an oring on the Accel pump linkage.

In all my testing, I came to the conclusion the needle was wrong for that motor. It was fat in the middle but lean on the MJ at WFO. The best setting I could get was 1 on the clip. I've gone to the JD needle and am pleased with that. I understand the 08 needle is a big step toward fixing the issue I found.

[avoidthedog]

ok thanks ill buy an 08 needle and see if that helps, if its still not enough what else could i do?

[JSanfilippo]

Play with your gearing as well, you might want to go a tooth or two bigger in the rear. The needle will make a big difference as the tapper is different. Most Yamaha's benifit from changing the taper. Pehaps you can PM "Burned", he is really good with jetting and needles.

Shouldn't really have to swap gearing unless he's riding super nasty singletrack IMO ? +1000 on the jetting though! I know these 250fs have at least some bottom end and what the OP is describing does not sound right.

Does the bike have the o-ring mod done to the AP. There was a very noticeable improvement in both response and power on the bottom end when I wired the AP on my cousin's 250f: thumbsup:

[evsracer912]

Clean the dang air filter!