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How do you know when to bore/hone cylinders?


jasonsb

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I'm rebuilding the entire motor from the crank to the pistons...How can you tell if you need to hone the cylinders to the next size? The walls look and feel smooth. The reason for the rebuild is a crank failure. I know it is safe to hone the cylinders but why spend the exrtra $80 if I don't have to. Is there a way to tell? Right now it is at 64.50.

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I just swapped in some Wiseco's and didn't bore out to the next size (still @ factory bore). Reason being, I hated that .060 clearance the factory slugs have; they're rattly and make less power. My cylinders showed absolutely no wear, and didn't have a ridge at the top. I took some 400 grit sandpaper and scuffed in a new crosshatch to make the rings seat and did the normal break in. No problems yet after 20 hard 4+ hr. rides. Personally, I would say that if you don't have crosshatch all the way to the top, the cyls. should go the next size up. They wear more at the top of ring travel and end up being out of parrallel as time goes on. In addition, if there is any ridge at the top, your new rings may have just the slightest bit higher contact in the cylinder, and can hit this ridge, causing instant damage. If in doubt, bore it out!

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I just swapped in some Wiseco's and didn't bore out to the next size (still @ factory bore). Reason being, I hated that .060 clearance the factory slugs have; they're rattly and make less power. My cylinders showed absolutely no wear, and didn't have a ridge at the top. I took some 400 grit sandpaper and scuffed in a new crosshatch to make the rings seat and did the normal break in. No problems yet after 20 hard 4+ hr. rides. Personally, I would say that if you don't have crosshatch all the way to the top, the cyls. should go the next size up. They wear more at the top of ring travel and end up being out of parrallel as time goes on. In addition, if there is any ridge at the top, your new rings may have just the slightest bit higher contact in the cylinder, and can hit this ridge, causing instant damage. If in doubt, bore it out!

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From the factory your pistons should not exceed .002 clearance,not .060.

 

I recently rebuilt the top-end on my 01' and the bores were well within factory specs,the original pistons had about.008 and .009 clearance after 110 hours of service.

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If the cylinders do not have that cross hatch to them you will want to hone them out. You said its $80.00, dont you know someone with a bit or something, or maybe a tool rental place. Just thinkin, cause thats a lot of $ just to hone out cylinders, unless you were talkin about boring them out too for that price. :shrugani:

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to hone is just cleaning the cylinders up.. when you bore it your shaving and honing (cleaning) the cylinders... gotta ask yourself how long has it been since you've redid the top end, has your bike ran to spec in that time, do i have low compression. if you dont want to spend the money then get a hone job.

 

are you on stock pistons?

 

i did a hone job just cuz i ride hard and just needed a good cleaning... bought me some new rings.. got a hone jobb and i was off.. runs like a champ! although i dont know how many times you can hone a cylinder before it needs a larger size piston.

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I'm rebuilding the entire motor from the crank to the pistons...How can you tell if you need to hone the cylinders to the next size?  The walls look and feel smooth.  The reason for the rebuild is a crank failure.  I know it is safe to hone the cylinders but why spend the exrtra $80 if I don't have to.  Is there a way to tell?  Right now it is at 64.50.

336690[/snapback]

From the factory your pistons should not exceed .002 clearance,not .060.

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My bad :jesterlaugh: ! I was looking at mm not inch measurements. Actually the clearance is supposed to be .0024 to .0026 (factory), so we're both off, me by a lot! Anyway, the aftermarket pistons fit noticeably tighter thereby giving less blowby and making more power. And as I look at the specs, I see that the maximum size is 64.1, so Jason's cyls. at 64.5 are in need of an overbore.

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I meant to say $80 for boring to the next size. The cylinder walls are real smooth...you cant really see the cross lines. I put in Wiseco pro lites last year but didn't do anything to the cylinders. I have never bored/honed the walls and I bought the bike used 2 years ago. I guess it's time to bore to the next size.

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