Mikuni 36mm Carb

Hi

I have a Mikuni vm 36mm single carb fitted to my Commando 850 Interstate, I would like to know if anyone has one that is jetted perfect for there bike, as mine seems to be a bit on the weak side, i dont know what jets are fitted but if i find out what the correct ones are that other people are using then this may give me a starting point , around the base of the plug seems to be the perfect colour but the electrode seems to go a very light grey especially on the right cylindar, i am running champion n7y spark plugs.

Thanks for any help with this.

Neil

My 72 750 has a Combat head and a Big Bore exhaust system
6DH3 needle clip in center
#159 type Q2 needle jet
The Main jet is 300 and pilot jet 40.
I realize that mine is a 750 but with the higher compression, and larger exhaust, this may be a good place to start.

The lighter gray on the right may indicate a a bad valve seal. I think you can replace it with litte to no trouble.
Your condition does not seem way out of wack. Just going up one jet size on the main may do the trick. These jets are interchangable amoung many Minuni carbs. Most dirt bike shops will be able to help you. They run the VM alot. You want to go up in number, for example 260 to 270.

I have an 850 MKIII with single Mikuni VM 36. Great carburetor once you dial it in.
My cylinders are .040 over so its a true 850. Megacycle 560NR cam.
Heres my setup:
25 pilot
159-P6 Needle Jet
6DH4 Jet Needle in #3 position with .020 shim under needle clip.
300 Main Jet (might go back down to 290)
0.7 Air jet
Air Screw is out 1-1/2 turns, right where it should be.

Bike idles great, runs great. NGK BP7ES Plugs have a light tan patina running the full length of the insulator.
Gas mileage runs around mid 40's overall. Don't just do throttle chops at speed. Do them at idle and putting along
at 50 MPH in top gear to dial in the pilot jet as well.

-Rick