Been a while, hasn't it?

Anyways, I'm now working on running the MC16 again, now with the dumbed-down MC21 carbs (pretty easy to install, actually), but one of the problems that I'm dealing with is the carbs overflowing (the bike actually starts and runs), and it makes it a pain to try to set up.

I think that the issue is that the previous owner of my cheap TA21A carbs messed up the brass tubes that go down into the float bowl when trying to remove them for some reason (circled in red in the image, how they should be on my old TA06 carbs). They were pinched and snapped off when I got the carbs, and I used a small drill bit to remove the brass and open the holes back up.

Is this what's causing my issue? If so, is there a place that sells the tubes? Or should I just get some brass tube in the right size and try to make some myself?

Welcome back!

As far as I know, the only place you're going to get those tubes, is from another set of carbs! Good luck getting them out undamaged though! (Sorry!)

I think making up some yourself, and epoxying them in place is going to be your best bet. Hopefully someone has a set of carbs on the bench that they can take a measurement from for you... I'm afraid all my spares (which included a couple of sets of F3 carbs) were sold last year, so I can't help any further.
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Andy.
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Not sure why I was afraid of trying to pull the ones from the TA06 carbs, maybe I thought that it would be more difficult since the previous guy messed up.

But nope, just jammed an awl into the open end to prevent it from being crushed and used some mole grips to wiggle it out. They aren't even glued into place and only have some light marks from the teeth, didn't even take 5 minutes

Just to be safe, take a close look at your float needles. The soft rubber tips get hard and don't seal as good after 30 years. Plus you should look close at the float needle seat as it might have some build up. I have found that a Q tip with a gentle compound, even toothpaste works, to clean the seat. The float needles can still be purchased as it's a common part across several Kehin carbs.

The above may not be your issue, but since you got the carbs off might as well have a look.


Last edited by ericandchi on Wed May 06, 2026 10:29 am; edited 1 time in total

Spookex2 wrote:Not sure why I was afraid of trying to pull the ones from the TA06 carbs, maybe I thought that it would be more difficult since the previous guy messed up.

But nope, just jammed an awl into the open end to prevent it from being crushed and used some mole grips to wiggle it out. They aren't even glued into place and only have some light marks from the teeth, didn't even take 5 minutes

Excellent! I wasn't expecting that!

I've never needed/tried to get them out, but I expected it to be a sod of a job! 🤣🤣🤣
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Andy.
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