Boring on a blaster

Boostwhipped

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Jun 11, 2017
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I tore my motor apart and it had a bad piston. The previous owner bored it out .020 and put a weisco in it. The walls have some minor scuffs so I'm boring it out another .020. My question is do I tell the machine shop I want it bored out to 66.040 and buy a new piston at .040 over?
 
Buy the piston first. Take it to the machine shop so they can match the bore to the piston. Remember, if you get a forged piston, you have to warm the bike up before riding to avoid 4 corner seizure.
 
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Oh ok I thought it was the other way around. When the new piston comes does it come with bore specs?
 
The blaster sizes are (66 being stock) 66.25, 66.5, 66.75, 67, up to 68.
Have the shop measure it first and then pick the next size up.
Then take the piston and jug back to the shop to get it bored.
55$ seams to be the rate for bore and hone.
 
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Cool thanks man I'll try that. Also I didn't tear apart the bottom end should I? The crank feels ok slides smooth and doesn't feel any grinding
 
i don't understand why even stress it at all
if a shop is going to bore your cylinder
why do you half to buy the piston?
bring the cylinder to the shop they will measure it order correct sized piston and bore it to the correct size.
 
i don't understand why even stress it at all
if a shop is going to bore your cylinder
why do you half to buy the piston?
bring the cylinder to the shop they will measure it order correct sized piston and bore it to the correct size.

That's what I do too. It's easier to let them get what THEY need to complete the job.
 
Should I still go ahead and tear apart the bottom end to check the crank? I have to topend off and can see the crank I don't see any thing wrong with it and still spins good no grinding or anything
 
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