Cylinder boring

[TJScott]

Hello, Im about to get my cylinders bored, right now the pistons are like 65.92 or something, but those are rare so I want to bore it out .80 over. What do I tell the machine shop guy when I bring the cylinders in? Like what measurements?

[fastbanshee8]

You need to take your cylinders to the machine shop, and have them look at them to see how far over they will have to bore them. Order the pistons, and take the pistons to the machine shop, so they can bore the cylinders to match the pistons.

[TJScott]

You need to take your cylinders to the machine shop, and have them look at them to see how far over they will have to bore them. Order the pistons, and take the pistons to the machine shop, so they can bore the cylinders to match the pistons.

Wait, what if it needs to be bored out more than my .80 over pistons?

[jasons]

Wait, what if it needs to be bored out more than my .80 over pistons?

 

 

have him measure first to see what size you actually need. then buy the pistons and he should measure them and bore to that size. i recommend jeff at FAST.

[firebanshee]

.080=66mil

[T_Shee]

yep firebanshee beat me to it. mine is .080 over and the pistons also say 85.92 right on them. you will have to go at least .090 over and thats a bit risky. as was said before take it to a shop they can tell you how much to bore. if its too much you may have to re sleeve or buy juggs

[TJScott]

so im having troubles here, my uncle came out with the measurement of like 59.98 on my cylinders, the pistons say 59.92

now to get .80 over, i need the cylinders to read 66.00, correct? now my uncle says boring isnt worth screwing with, and that we could get that with a hone.

now, does that sound the least bit safe? do you think they can really get it accurate enough with a hone? and those measurements are fine, right? my cylinders need to measure 66.00 to get some .80 over pistons in there, correct?

sorry, i know nothing anymore, ive been working on dirtbikes for years, but with banshees, im right back to the start, with lack of nikasil cylinders and such.

[blaster2006]

so im having troubles here, my uncle came out with the measurement of like 59.98 on my cylinders, the pistons say 59.92

now to get .80 over, i need the cylinders to read 66.00, correct? now my uncle says boring isnt worth screwing with, and that we could get that with a hone.

now, does that sound the least bit safe? do you think they can really get it accurate enough with a hone? and those measurements are fine, right? my cylinders need to measure 66.00 to get some .80 over pistons in there, correct?

sorry, i know nothing anymore, ive been working on dirtbikes for years, but with banshees, im right back to the start, with lack of nikasil cylinders and such.

 

how is it 59.92? if stock is 64.00? type?

[sheefreak]

Yeah, something is not right. Measure again. Also, a hone simply cross hatches the cylinder. Does not remove much material at all.

[boneyardbanshee.]

Yeah, something is not right. Measure again. Also, a hone simply cross hatches the cylinder. Does not remove much material at all.

^ yes. at best honing will smooth out very light scratching. Anything more will need a bore.

[kawiking]

http://www.wiseco.com/PDFs/Catalogs/CB07/YamahaATV.pdf

64.00 is stock cyln then goes .25

.25 -- 10 over

.50 -- 20 over

.75-- 30 over

65.00mm -- 40 over

 

and so on.

[TJScott]

lol, sorry guys, typo.

it was 65.98