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Amazing, I love this forum. Yes, although if never been able to find it, I think this is it! I got the ones for the OEM CV carbs printed and this looks similar but for the VM. Thanks
My VM equipped bike REQUIRES choke for cold start and warm up, about the first minute's running is dodgy unless I am nursing (I have two separate) chokes/enricheners.
I fought poor sealing float needle valves for quite a while on several VM carbs.
There are also a couple different float settings depending on when the VM was built older carbs used a different setting.
Just a heads up if purchasing replacements, there are several VM float valve throat sizes.
Sounds like it may be a tad rich on the pilot jet or mixture screw. Note that on a VM carb, mixture screw IN gives a slightly richer idle mixture, screw OUT will make it leaner. This is OPPOSITE to how it works on the stock CV carbs.
The "rule of thumb" regarding idle jet size and mixture screw is that you want to end up with the mixture screw between 1 or 2 turns out from seated.
And the basic method is to find the idle mixture that gives the highest idle rpm. So with a fully warmed up engine, tweak the mixture screws to see where you get the highest rpm. If that happens with the mixture screws more than 2 turns out, you need smaller idle jets. And with highest rpm with the screws less than 1 turn out indicates a need for larger idle jets.
And as always: Before attempting any carb tuning, the engine must be in decent condition and adjusted correctly. That means good compression, correct cam timing and timing chain tension, correct valve clearances, new or clean air filters, and correct ignition timing
Maybe cool too share that after fixing the timing tooth earlier this year, I pretty much rode the bike every day to work and to France for a trip this summer.