Right main jet with piston with bevel to change exhaust timing

[David Hearn]

Hi,

I am replacing a 66mm piston on a bone stock (stock exhaust, Mikuni carb, porting,etc) machine with a piston that has the bevel on the front side that changes the exhaust porting. Someone said I need to change the main jet to match. I operate machine at 100 ft. altitude.

Can you give me a recommendation on what main jet size is appropriate with beveled piston?

Thanks,
Dave
(just bought 3 Blasters to rebuild for family-'88,'98,'03)

 

[Larry's Shee]

Get ready for a crazy power and . I did the exact same thing with a Vito's superstock. Which I hope that's what you got.
So, you're putting a new piston in a warm out hole ??
Not a good idea.

As to jetting, IIRC I used a 260, it was on a fliipper, so I didn't bother to remember

I sure hope you're using a forged piston !!

 

[David Hearn]

Thanks for the advice on pistons, boring out cylinder, and jetting, I really appreciate it! Dave

 

[Larry's Shee]

Good answer.
As to the power band , it will have unbelievable bottom end, but just as you expect that two stroke smile, it stops pulling and you HAVE TO shift, it won't rev any higher. I actually posted a thread like this 5-6 yes ago.

 

[Larry's Shee]

https://www.blasterforum.com/threads/what-jets-are-you-using.28981/page-5

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