Sea level jetting - Model 94 Wombat + mixing question

[Simonkav]

Guys,
I'm working through a recently acquired, long sat model 94 wombat with the model b carb. It's running, albeit very rough, inconsistent, and after some basic going over I really feel is fuel system/carb related. It should be done regardless, so I'm going to go through everything from tank > petcocks > lines/filters > carb. Once I'm in the carb, I'd like to make sure I'm at recommended jetting. I'm in coastal CA, typically at or near sea level, almost never over 2K feet.

I realize there is likely no one-size-fits-all guaranteed to work gospel, but do any members here have experience at this elevation with jet size, clip position, etc?

Since I'm new to two-strokes, I'm also new to mixing oil and gas. Let's say, hypothetically, somebody were to roll out on a stock 1972 wombat in Athena, Oregon but in the 2018 world of premix oil and 91-octane unleaded gas, would it still be mix at 20:1 as per manufacturer recommendation? I've searched the boards and seen a lot of reference to 32:1 but I don't know why.

Thanks!

-Simon

[Simonkav]

Also, am I crazy that the shop manual says use 3/16 ID fuel line, the petcocks seem to fit fine to that, but the connection on the carb looks way bigger, like 5/16?

[thrownchain]

Because of the better quality of modern oils most people have dropped to a lower fuel/ oil mix ratio. So 32 to 1 is a popular level. Depending on the type of riding you could go to 36 to 1 or less.

[Bill2001]

If the carb has a larger fuel inlet it is not original-- later ones have the large inlet. Gently heat the tubing end with a heat gun and stretch it over.

[Joe Ormonde]

Bill`s right. It could be for a Yamaha AT2. Post a photo and better yet take it apart and post that too. Write down the markings on the slide, needle and all jets. A lot of guys in this site can help you best when they can see what you have.Joe.

[Simonkav]

Thanks guys - I went through it and running felt better, but started flooding. Stuck float. Pulled it apart again, same thing. Stuck after a few minutes of running. I'll have to diagnose further. Maybe the floats are filling? The action seemed fine. I adjusted the level slightly. I tested the valve just using air through the fuel inlet and it seemed good, I could not get air through there when seated. I will definitely take some photos and take markings on the jets next time as I need to get into it again.

Cheers,
Simon

[viclioce]

Pull the floats out & shake them. If they have fuel I. Them you’ll know it. You’ll need to let them empty out. Find the hole by tipping around until you find the hole. Once found, IF the hole isn’t large, you can use solder to seal the hole. If it’s too big, try 5 minute epoxy! Victor