New to 2 strokes.

Leakdown test shows a leak on left side. Crankcase seal? Anyone got a link on how to do it?
 

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Ok got to order the flywheel removal tool. But is it safe to say that is what is leaking? Or is there another seal behind it that could be leaking? I would rather arder everything at once so when the parts get here can put it back together all at once instead of waiting a couple more days to finish the job. Also is there a way to tell what jet size I have? Numbers on the jet I can cross reference?
 
Nope...just one seal.
The main jets have the number stamped right on the end by the hole. Sometimes on the side.
Pull off your float bowl and you will be able to see the number.


The jets look like this...

Mikuni_Main_Jets.1.jpg




 
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Mine has a 310 in it right now. I am trying to adjust the floats according to Awks thread but is there anyway to tell what carb I got? I measured the opening on the carb that goes into motor and the inside diameter is 28. Is that how you tell what for carb you got?
 
That's a Mikuni VM26...a stock carb that came standard on the Yamaha blaster!
A great carb! Easy to tune!

Your measurement is 28mm, but carbs are measured on the inside...
26mm is the venturi size inside the carb. The smallest diameter inside the carb.
The area where the needle goes up and down.

This carb works great with porting!
 
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I read on here somewhere you measure the opening that goes into engine. I need to order parts for it are you sure it is the 26mm?
 
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I really hate doubting ppl when they are helping me but I just found the forum I seen earlier. Go to engine, then carb. And look down about halfway their is a thread called Help no idea what carb I have... Then scroll down to where" jus me" chimes in. He said to measure the inside of the smaller "intake side" of the carb.
 
Its ok to doubt people. Always Ask questions.
I was taught that it was measured at the venturi. Hell, I could be wrong, but I don't think I am.
If I am wrong, then I just learned something.
I just measured a stock blaster carb in the garage and its like 27.95mm. However, when you look inside you can see a minor "step" inside the carb.

Bottom line... you have a stock blaster carb. That I'm positive about.
 
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Lmao, so I will have a 32 mm carb after I do this. Thanks again I bookmarked the first one read about halfway. Good learning material on that.
 
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