Mikuni TM Carburetor Review

Braaaptor

Member
Dec 1, 2009
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Hamlet, NC
Woot! First one posting again! Lol.

I've been running a Mikuni TM series flat-silde carburetor on my Blaster for the last month, and since most people here run Keihin's, I figured I'd review my Mikuni for those who might want to try and run one.

Carb is well-built, and the price was decent at around $ 150.00 brand-new. It uses a mechanical idle-speed adjuster, which is great. Its just a tapered bolt which holds the throttle slide up. No funky airscrew idle adjustment like the OKO 30mm's use.

The carb bolts right up to the engine, but you will need a reed spacer to get the carburetor to clear the clutch arm. I also had to grind down the carburetor's casting to get it to clear the lower left intake boot bolt. Not hard to do, but necessary.

It comes stock with a plastic slide :eek:, but so far I haven't had issues with it. The stock 5fp17, double-tapered needle is too rich for the Blaster engine. I am still in the process of tuning to find out which needle works best on my setup.

The carb has a very stiff throttle return spring. I cut a couple coils out of mine to ease the stress on my thumb while out riding. Any aftermarket throttle cable will work with this carb.

I'm running a 290 main and a 35 pilot as of now. The engine likes the main jet, but the pilot needs reduced one size. I'm still tuning. It is snappy in throttle response and easy to work on. The float bowl comes right off; no hassles like with the OKO's and some of the Keihins. It also has a plug in the bottom of the bowl, which you can remove to change the main jet without pulling the bowl off.

Overall, this carb is a nice upgrade over stock for a ported engine like mine, but it is difficult to tune since I am one of the only ones on here running one. Its a lot of trial and error. I like this carb and will recommend it to anyone, but we've got some researching ahead of us when it comes to tuning.
 
Woot! First one posting again! Lol.

I've been running a Mikuni TM series flat-silde carburetor on my Blaster for the last month, and since most people here run Keihin's, I figured I'd review my Mikuni for those who might want to try and run one.

Carb is well-built, and the price was decent at around $ 150.00 brand-new. It uses a mechanical idle-speed adjuster, which is great. Its just a tapered bolt which holds the throttle slide up. No funky airscrew idle adjustment like the OKO 30mm's use.

The carb bolts right up to the engine, but you will need a reed spacer to get the carburetor to clear the clutch arm. I also had to grind down the carburetor's casting to get it to clear the lower left intake boot bolt. Not hard to do, but necessary.

It comes stock with a plastic slide :eek:, but so far I haven't had issues with it. The stock 5fp17, double-tapered needle is too rich for the Blaster engine. I am still in the process of tuning to find out which needle works best on my setup.

The carb has a very stiff throttle return spring. I cut a couple coils out of mine to ease the stress on my thumb while out riding. Any aftermarket throttle cable will work with this carb.

I'm running a 290 main and a 35 pilot as of now. The engine likes the main jet, but the pilot needs reduced one size. I'm still tuning. It is snappy in throttle response and easy to work on. The float bowl comes right off; no hassles like with the OKO's and some of the Keihins. It also has a plug in the bottom of the bowl, which you can remove to change the main jet without pulling the bowl off.

Overall, this carb is a nice upgrade over stock for a ported engine like mine, but it is difficult to tune since I am one of the only ones on here running one. Its a lot of trial and error. I like this carb and will recommend it to anyone, but we've got some researching ahead of us when it comes to tuning.


Good post bro keepem coming
 
I've ran a TM28 for awhile, it does not have plastic slide, fits perfect into stock size intake 34mm but requires needle replacement and was a biotch to tune....
 
watch that main jet when reducing the pilot
all jetting circuts will have an effect on the circuts above it
 
Where did you get it? Linc maybe?

Here's the best price I've found on one brand-new:

Mikuni Geniune TM 34mm 34 mm Flat Slide Smoothbore Carb Carburetor TM34-2 | eBay

@PikledBeats, you're right. The older TM carbs do NOT have a plastic slide, and even the newer smaller (28mm) ones may not. I'm not 100% sure. I know all the old 34mm TM's which came off LT250r's had the metal slide. Needle changes are a necessary hassle to make one run properly on a Blaster, but I think it's worth it in the end.
 
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As an experiment, I am just about to fit a 34 TMXX D slide, what needle would be recommended for a stock motor, DMC Alien pipe, foam filter direct on carb throat, dual stage reeds, reed spacer block, 25:1 pre mix?
 
As an experiment, I am just about to fit a 34 TMXX D slide, what needle would be recommended for a stock motor, DMC Alien pipe, foam filter direct on carb throat, dual stage reeds, reed spacer block, 25:1 pre mix?

Honestly, you'll just have to do some experimenting and see which needle runs best with that setup. I'm running a 5FP17 needle with my modified engine (ported/polished/redesigned head) and it's just slightly rich on the bottom end. I don't have any firsthand experience with a 34mm Mikuni on a mostly stock engine, but I'd get a needle two or three sizes leaner than the 5FP17 and tune from there. Here's a needle chart that may help 'ya out: I:I

http://www.sudco.com/vol33/56-59.pdf
 
Dang good price on that. Tough choice cause I'm thinking I'll only go with a 30mm. Good info here. I:I


This is the one thing that sucks regarding the TM series ... their is no 30mm. It is either the 28 or the 32. The 34 is highly regarded by Ken for his ported motor setup. I have always wondered how a 32 would run on a stock jug though.
 
Is this the carb you guys are talking about? If not can you please identify it? sorry to res this thread.
http://www.planetcalypsoforum.com/gallery/files/4/3/7/8/6/dscn5793.jpg


sorry this is it>
dscn5793.jpg
 
he hasn't been on here in a couple years
 
Thx AWK !
Jimmer Hey buddy i did notice you ran that carb also. I am just looking for a starting point on the jetting with this carb. I live in florida so I am at sea level so i understand every location is different. Do you remember what jets and needle you used? i tried to send a message but it wont let me. Thanks
 
any help?? I' wondering if ayone completed this swap? I bought it and was unsure if the needle it come comes with works or what needle do I need? An I figured 260 main, 32.5 good to start out???