Mikuni 36mm VM carb set

[flaguy54]

Trying to build my first cafe bike and ran into a problem. Actually many problems, but this one I need help with.
Ordered a Mikuni 36mm VM carb set from 650motorcycles.com. The web site said they would be jetted and set for my bike so just put them on and ride. Might have worked had someone helping me not started messing with the rich/lean settings immediately. Can anyone tell me how to get these carbs back to their original settings. Emailed the vendor/supplier but no luck yet.

Jay
79 xs 650 with modified exhaust

 

[rybeatty]

They always say they are jetted for your bike but depending on where you live affects how it will run. Air temperature, humidity and elevation are all things that play a role in jetting. I have never run a vm36 tho I have considered a single 36. I have 34's but they can't be much different. Is it a single carb setup? I would get do some more research get some jets, plugs and the mikuni tuning guide.

 

[DIRTY DOG]

start with the air mis screw 1 turn out

 

[rybeatty]

you could start there and see how it idles but that maybe in kind of far. Back it out till you get the best idle. Is it a single carb setup?

 

[rybeatty]

Your air mix screw and pilot jet work from idle to about 1/4 throttle

 

[flaguy54]

Thanks guys. We made some progress on this and got it idling better. Unfortunately there seem to be more issues. It looks like maybe time to throw in the towel and admit I was an idiot for buying a bike on Craigslist unseen. A local fellow who rebuilds these bikes and motors offered me one of his finished bikes for mine plus $2500.. I was looking at having to put $2500 more into this one so I may do this and end up with a bike I can ride right now. He's got a '78 with 3300 mi and it's been refurbished including digital ignition. I'm gonna lose some money on this but hey, my fault. It's expensive making bad decisions.

 

[Herd]

What kind of issues? You could sort out quite a lot of issues for a fraction of $2500. Not to mention, build your own bike. Kind of a journey vs destination thing.

Was that 3300 original miles or since he "refurbished" it. What did he do besides ignition? It might be worth it, might not. Really depends what was done to it and what you are willing to part with to get it.

I think you can save yourself some money and get your bike running right. You will actually gain some very valuable experience as well, which you will not get if you buy somebody else's ride. Sooner or later, you are gonna need to repair, fix, or tweak something.