Hey Guys, I know it has been a while since I have posted, been busy with work, but I have still lurked around the forums And I have looked on the threads for answers to my questions! I just don't find anything definitive. I saw an amazing thread that someone started where everyone listed their setups to the detail but I did not find another setup like mine. So last weekend I did the BB351 and TM 34 carb, I spent my time with heat cycling and small rides and changed the oil to break in the kit and now I am looking to tune the carb. I have the airbox lid removed, UNI filter, stock gearing, smog deleted and am at Sea Level. On the factory carb I had the DJ klx300 jet kit with the 128main Jet, Bill says to go up two sizes on the TM34 when you do the carb switch so I installed a 130 main (not sure what brand jet, its what was at the local bike shop). I can feel that bike is very responsive compared to the old carb, she idles fine part throttle (up to 1/4 throttle) cruises ok but started to break-up/sputter/hesitate after 1/4 throttle and then fell completely on its face and had no power after 5k, and would just go nowhere if I instantly go to WOT. Today I installed a 135main and took her for a ride and the bike felt way better, more torque, better response but acceleration is still choppy during aggressive throttle and really breaks up at WOT, and then would completely shut off at a stop to the point where I had to let it sit and choke it to start it. Since Bill says to only go up two sizes in the main I don't want to jump up to a 140 (my local shop doesn't have the 137, so I would have to order it). I am going to play with the needle now but I could really use any insight/experience that anyone else is willing to offer. I know this 351/tm34 setup is a monster waiting to be unleashed and I really can't wait to get it to that point!

Thanks in advance!

Dan

 

The 128 dj in your kit flows like a small round stock style keihin jet, The mikuni tm jets flow different. So to say go up 2 sizes is kind of confusing. he may mean 2 sizes bigger than what works with a 250 using a TM?

I recently ran into this on klr that had a 147.5 mikuni jet in it instead of a Keihin 148, it was way lean with symptoms much as you describe. The bike shop sold him the wrong jet because they look very simular.

 

Interesting, I guess Ill go with the 140 that came with the Mikuni and see what goes on, I cant figure out how to get to the needle. Thanks RimBender!

 

OK, so I went back to the 140 main that came with the TM34 and the bike feels better, picked up the front a little with a quick 2-3 shift, but it stills breaks up at high rpm. Also, after ridding for a few minutes and ripping on it the bike stalls at idle and wont start until it sits for awhile and then I even need the choke pulled out to ride the few blocks back to my house. IDK, help? If I cant figure this out the bike might just go on the local dyno to get tuned, but I would rather have it close so it doesn't take as long/cost as much.

Thanks again,

Dan

 

Oh yeah, and I went to adjust the needle and I cant figure out how to get to it, but maybe I'm just a tard, no more responding to myself on my own thread today. Later!

 

http://www.mikuni.com/pdf/tm33.pdf

Sorry can't help w/ jetting, wifes klx350 running a fcr35

 

Pull the top cover from the carb. You will see the top of the needle in the center of the slide, held-in with some sort of retainer. Remove the retainer and pull the needle out of the slide. Change the clip on the needle to the next lower groove (toward the tapered end).

Assembly is in the reverse order

 

I was having trouble jetting the tm. I couldn't get it to richen up, flatened out on the top. I had the airbox lid off also. Called Bill and he had me close up the box to an opening about 1 3x4 by about 5 if I remember right. I ended up with a 147.5 main. I'm at 500 foot above sea level. I think Bill said they run the 200 snorkle on theirs.

 

Have you tried adjusting the pilot screw to help the startup?

Ride on
Brewster

 

When using the TM33/34 mikuni carb you must run with the air box lid on other wise you will have a lot of trouble trying to jet the carb. The jetting that I installed in the carb should be close.
Bill