I finally got time to work on it today. It is the butterfly carb. The first thing I found was the spring on the choke butterfly was broken. That's why the choke wouldn't work. I bought a spring at the auto parts store and got it to work. It was too warm today (81) to find out if that is going to fix the cold start problem.

I fired it up and got it warm. Then I sprayed carb cleaner around. It seems there is an induction leak at the lower part of the intake where the carb bolts up. I don't see where it shows a gasket in the book, just an insulator. Do you think it be leaking there and just need to be snugged up? It's possible it could be a boot, but the rpm picked when I was trying to spray directly at the mount bolts. Unfortunately, most of my tools are at the racecar shop and I didn't have a long enough extension to check it today.

 

You can get false readings from the carb or other type cleaner sprays on intake leaks, I believe that water is the best ticket from what I'm told on checking intake leaks, I think I would get a good Mikuni as suggested if you have the funds, if you plan on keeping the bike, they are easy to tune and would upgrade you to a much better CV carb over the butterfly unit. Has this bike sit for a length of time before you aqquired it?

 

I think I will be changing the carb eventually. I'm just trying to improve the rideability until I can replace it. I've got to recover from Christmas and off season racecar maintenance first.

The bike hadn't been registered for a couple of years, so yes it did sit around. Little things, like the turn signal switches, weren't working properly when I got it. A little contact cleaner and some use took care of that.

Monty

 

If it has sit that long and it's going to be awhile before the new carb, I would take that one down and make sure the needle and seat are good or heck just go ahead and put a new set in, clean the jets out and all passages, check the float height, make sure the floats are good, the basic clean and inspect everything. Put new intake gaskets back in as well.