Mikuni TM34 - non pumper

[Tim of DO THE TON]

So - I have a pair of TM34's sitting here staring at me.

I've been running their round VM cousins for a few years and like them. Have VM34's on my 750cc rephased XS engine, VM32's on my BMW R75.

Thinking about trying the TM's on my XS, which hss a 750cc, Shell #1 cam grind, enlarged titanium valve, ported head motor.

They are currently set up with:

4.0 Slide
190 Main Jet
20 Pilot
6DH2 Needle
P4 Needle Jet
Needle clip 2nd from top position

Found one baseline recommendation of:

190 Main
25 Pilot
6F9 Needle
P6 Needle Jet

Of note, nobody seems to make mention of the slide cutaway spec. I'm tempted to simply set them up as per the provided baseline and see what happens, but am looking to see if anyone has actually set these up on the XS and has some recommendation as per the slide etc.

I've searched, and there just doesn't seem to be much conclusive discussion on the topic, hence my beginning a new thread on it.

 

[ProSimex]

Throw em on and see what happens man!

 

[Tim of DO THE TON]

Well yeah, but still - I'm sure others have sorted these out. Just can't find any notes/discussion on the slide component and those get expensive to simply buy and try. I have an assortment of jets, needles and needle jets but not flat slides.

 

[Sonnylynnvick75]

I'm in the sam predicament, I'm almost done with my 650 rebuild and I decided to replace the stock carbs with a set of tm34s but have no idea how to run them.

 

[650performance]

TM34s will support over 70 RWHP; while properly set up VM34s can handle about 64 - 65. A good baseline for a high performance 750 with over 10.5 - 1 compression ratio, Shell #1 or hotter cam, free flowing exhaust and a good flowing head is as follows:
Main jet 200 to begin with, but 190 will probably be better if it isn't too lean
Slide 4.0
Needle 6DH2 or 5EH7 with stop in the middle groove
Needle jet P-4
Pilot 30 @ 2.5 turns out (can also try 25 with 1.5 turns out)
Air jet 2.0
Obviously, engines differ and people live at different elevations, but these specs work very well near sea level in temperate weather.
The TM34 is so much more carb than a fairly stock motor needs that I have no idea what settings would be a good starting point for a warmed up 650.

 

[Tim of DO THE TON]

Awesome! Much appreciated. Thankfully I have the 4.0 slides already.

 

[Tim of DO THE TON]

Just got home to compare the recommendations against the current setup. As it turns out, the only difference is I have a 20 pilot in there now, but have plenty of pilot jets sitting around. Have to pull the airjets to see what size they are. But everything else is a dead match, which is awesome.

 

[xs650dreamer]

so what happen with this man ?

 

[Sonnylynnvick75]

I'm not sure about him, but I got mine set up and running really well.