Quick Mikuni/general carb question..

SClay · Full Member Joined: May 30, 2008 Posts: 93

..I never did quite realize this, but you cannot mount a carburetor, in this case, a Mikuni VM, angled downward(in relation to the engine, with the filter bore being lower than the throat bore at the engine) can you?

Can anyone confirm or deny this? It just suddenly dawned on me that if you did this, it would starve the pilot circuit of fuel. No?

Steve

metalredneck · Full Member Joined: Aug 04, 2008 Posts: 308

I believe the angle is fairly crucial. Most carbs are horizontal, but the carbs on my ol' VF 1000 v-4 were angled down, in a v-4 configuration. Float levels you may be able to compensate for, but venting & jet placement will be sketchy.

JeffM

It would affect your float setting for sure, even a mm can make a difference.

You may be able to compensate by changing the float setting. Perhaps experiment with some sort of zip-tie hanger off the frame with an eye to building a bracket??

Jeff

SClay · Full Member Joined: May 30, 2008 Posts: 93

Another question folks, as I am having contradicting bits of information here. On the VM34 Mikunis, the mixture screw, in what fashion does it function?

Now, I am looking at the manual, and there is a graph. And it says that screwing the mixture screw in richens up the mixture, and backing it out leans it out. And then other places say it is the other way round.

Which is it? I can't believe I even have to ask this, but the VM manual leaves a bit to be desired in the translation department, and I just want to get a straight answer.

Or maybe my brain just hurts a little bit from battling with this thing.

Am I correct with this theory:

At Idle/low speed, there is enough vacuum being generated by the inlet air to pull fuel up from the pilot jet. But you alter the actual fuel ratio by only adding air to this particular mixture, before it enters the actual intake charge, and then traveling to the engine.

Am I close to being correct?

Please however, correct me if I am wrong.

Steve

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