VM34

Jerry Doe · Jun 27, 2009

Hello -- First thanks for keeping the forum alive and kicking!!

I am going to try this VM34 MM MIKUNI single carb on my 850. It is a used one and has jets, slide that was on the bike before mine. I am sure I am going to need to tune it. I have standard cam now as is the rest of motor -- except well skimmed cylinder head.

I heard there is a Mikuni tuning manual. Has anyone got a copy of it? I could use it as am new to the world of Mikuni Carbs. jerry [at] accessnorton.com
Cheers-- Jerry

L.A.B. · Jun 27, 2009

VM manual: http://www.mikuni.com/pdf/vmmanual.pdf

splatt · Jun 27, 2009

There is plenty of info on jet sizes & settings,most of it is pretty close,I would set up to those before fitting,you'll find you need a 90* throttle cable bend, and you may need to add a slide spring from an anal carb to stop the slide sticking occasionally.

GRM 450 · Jun 27, 2009

Hello Jerry,
sorry to change the subject, you said a skimmed head, was this done for any reason other than the surface was poor due to bad casting? as mine was, or another reason?
Thanks for a great site, the information here is outstanding.
Regards Graeme.

debby · Jun 27, 2009

You may also be interested in the Victory Library Mikuni manual, published by forum member "panic" :

http://victorylibrary.com/MIK-BT.htm

And I would imagine Stan Smith at Rocky Point Cycle would be happy to give you jetting recommendations if you gave him a call.

Happy tuning,
Debby

Jerry Doe · Jun 27, 2009

Thanks All! Exactly what I needed.

YES-- Re surfaced head only, but it's been done a few times,

Cheers

bpatton · Jun 27, 2009

I just dropped the bowl off of my single Mikuni VM 34mm to check the float level height about two hours ago. I have a Sudco tuning manual but it doesn't have the exact dimensions of the height for the VM34 that the Mikuni Super Tuning Manual does. I had been told that the arms for the float valve should be parallel with the bowl gasket surface when the valve is seated. This is excellent! I couldn't be happier if I was twins. I'm going to recheck it tomorrow. The reason I checked in the first place is I can't keep the plugs clean in the low throttle cruising mode. I'm using a 3.0 cutaway slide and #30 pilot. Both of these worked out years ago, but now it won't run as crisp and cleanly this time around. Same aircleaner, pilot, and slide. Maybe it's the gas?

Hortons Norton · Jun 27, 2009

I have heard that a 2.5 is the one to use, And that was a reliable source.

Jerry Doe · Jun 28, 2009

mine has a 2.5 slide in. I will let you know how it works...

VM34

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