question on cylinder

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osobad
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question on cylinder

Post by osobad »

I hear people on here talking about the cylinders and plating on the KDX. I am going to be taking a look at mine and how will I know if it needs to be replated? I have always either replaced rings or had it bored over when rebuiling top ends. This plateing is new to me. If the cylinder looks ok do I just replce with new rings or piston and rings if it is out of spec?
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fuzzy
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Post by fuzzy »

If the plating looks good, just 'deglaze' the cylinder with some WD and scotchbrite(actually do this first, and you'll get a good look at the plating)...Install new piston/rings.
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scheckaet
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Post by scheckaet »

post good pics in there if you're not sure.
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Post by SQLGuy »

Depends what year. The earlier ones had electro-fusion bores.... effectively, steel welded into an aluminum bore. If you bore those, you have a plain aluminum bore, that's way too soft for use. The only real choice with those is to bore them out to take a sleeve, then bore the sleeve to the correct diameter for the new piston and rings. You end up with something like a new cylinder, but it's expensive.

I think you're in more or less the same situation if you bore Nikasil, but I'm not sure.
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scheckaet
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Post by scheckaet »

you rarely need to bore out and put a sleeve unless the cylinder has some real deep gouges and can't be stripped and replated.
I'd say 99 % of the time the plating is worn and the aluminium is good underneath. strip and replate is all you need, good as new.
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fuzzy
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Post by fuzzy »

If the plating is worn, send ti to a reputable place. They will bore it and lay the right amount of chrome/nickel/whatever back down. They all request a piston to be sent with the cylinder. I would recommend against an iron sleeve.
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
osobad
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Post by osobad »

well I had ashop look at it and even though it looked pretty good and compression was 145 it had a slight edge around the bottom of the cylinder so i had him send it to mulinium I beleive. The guy at the shop said he has ben using them for a long time and the do good work. I could have prob got buy with replacing the rings but I have the top end off might as well do the things I want now instead of later
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scheckaet
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Post by scheckaet »

millenium.
As long as it's NOT "US chrome" you're good.
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fuzzy
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Post by fuzzy »

Well, you're plating will be good for MANY pistons now.
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
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SS109
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Post by SS109 »

>|<>QBB<
scheckaet wrote: As long as it's NOT "US chrome"
No doubt! I have a cylinder plated by them but I think I'm not going to use it. I think I'm going to send my original cylinder to Millennium to get it done right.
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