TM34 setup - help, please!

[zippy49]

Hi all, moving this request from the "installation pics" thread.

I have the TM34s mounted and jetted, but my Traveller is unsafe to ride because they stick shut when decelerating on closed throttle. Opening them is nearly impossible unless you fan the clutch. The throttle is completely free otherwise.

Another user mentioned putting a big spring on them... as in something that resists the slides closing all the way? Or helps open them? If anyone can shed some light on this, I'd be very grateful.

[DAVID THOMPSON]

sounds like you're drawing a lot of vacuum when slowing down

may have a vent in the carb plugged off
dave

[zippy49]

Hi David,
Thanks for the reply. Yes I already figured out that the vacuum is very high. But the carbs work perfectly otherwise, the bike starts and idles, etc.
I have all the drawings and description for the 33mm version of these carbs. They appear to be a simple slide/needle design, with no extra features except for the accelerator pump. Heck, my old SR500s came with this feature. Is it possible that this circuit provides an air bleed at closed throttle? I have not adjusted it, the carbs were purchased new from Vintage Spoke.

[Srinath]

You missing the throttle stop screw or the idle stop screw ?

You cant have higher vacuum unless you have modded the motor.
Cool.
Srinath.

[zippy49]

There are no missing screws - the carbs are as delivered except for #130 main jets and moving the bell-crank down to clear the tank. The Kedo website has a poorly translated description that mentions assisted opening and closing, but I can't see any such mechanism in the drawings.

The motor is stock, but still makes a lot of vacuum when slowing on closed throttle, clutch engaged. The stock carbs must have had some sort of air bleed. I note that 50mm flat slide Mikunis sold for Harleys feature a roller bearing slide.

BTW it is nearly impossible to access the LH main jet as it is right over the starter motor. After hours of fiddling and searching for dropped jets, I came up with the perfect tool. I use a ratcheting right angle screwdriver to loosen or tighten the jet, then slip a 3/4" long piece of 1/4" fuel line over it and it spins right out (or in) with two fingers. Piece of cake!

[DAVID THOMPSON]

inspect the slides carefully
i had one in a bmw sticking once someone had dropped it on the floor and it had a burr on the bottom edge that made it stick
dave

[zippy49]

Was that a new carb? Hard to believe that a brand new carb set would be damaged. Also, the slides are completely free if the bike is in neutral or the clutch disengaged. But it looks like they have to come off anyway. Something is not right and unfortunately Vintage Spoke (the vendor) has not been much help. And don't even mention Sudco...

[OLDMTNCARVER]

I would suggest a call to Galen Miller at Bikeworx.
Better yet, just send him the carbs.

OMC