Been cleaning the carburetor up again, and I just realized I don't know what is in that opening below the orange mark. That's where a tube from the upper section goes into, and it doesn't look like it's a jet, it doesn't have a slot for a screwdriver. Looking on the Partzilla diagram, it doesn't mention anything about it.

 

There will be a small fixed brass jet in the bottom (well, there should be!) and this is for the choke/cold start. Squirt some carb cleaner or the like down there, just to make sure that it isn't blocked.

For the Yamaha twins, only the left hand carb (with the choke lever) has this opening - on the other side it is blanked off. Poor starting can sometimes be down to the float bowls being inadvertently swapped over.

Excellent, I appreciate the information! I did make sure that it's clear, then I blew it out with compressed air. It does look like there's a jet down there, it just doesn't have a slot for removal .I'll go ahead and put it back together and see what happens.

Hey Tom your last sentence would make an awesome T-shirt.

Put it back together and see what happens!

I'll have to print those up and start selling them here :0)

It's running great, though it was running well before. Carburetor is a lot cleaner though, and it was idling about 150-200 RPM more, even though I didn't change any settings. I turned it back down to about 1200. I think the pilot jet is cleaner than it was.

Never use that purple power on aluminum
My old corvette parts can attest to that

Another question on the carburetor. The air adjustment screw seems to be connected to the larger hole in the center of the bottom of the mouth of the carburetor. The small open hole on the right doesn't seem to go anywhere. Is that correct?

 

New to the site today, I've used Simple Green with good results

Most cleaning items for Ultrasonic Units can be purchased at the .99 cent store. You do not need to spend $7.99 on something you’ll use one time.

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