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KX85 cyl. boreable?

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I am rebuilding a KX85 motor for some kid and the piston shattered causing some minor damage to the cylinder. Are these nikasil coated cylinders or can they be bored? Thanks!

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After doing some reading/searching I came across another question. Would it be possible to put a KX100 cylinder on this bike? Most of the engine part numbers are the same.

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Two things you can do:

1. Bore the 85 cylinder out the 100's bore and not re-port it - low/mid-end powerband.

2. The 100's cylinder/head fit. :thumbsup:

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Two things you can do:

1. Bore the 85 cylinder out the 100's bore and not re-port it - low/mid-end powerband.

2. The 100's cylinder/head fit. :thumbsup:

Are you saying you get better bottom end from a bored 85 vs 100 cylinder?

dp

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Is the cylihnder not plated, meaning a bore would require a replate??

Yes the OE cylinder is Plated. The plating would be Electrofusion.

When in dought try the magnet test.

A magnet will stick to Iron bore like glue.

Any overbores will have to be replated.

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Thanks for all the help guys! Looks like I will be ordering a new 100 cyl. and piston kit, as well as a new crank and all the other parts to put her back together.

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i had a leaky head casket on my sons 06 kx 100 which caused cylinder damage,my mechanic Friend told me i have two options the first being the most expensive was to re cut and re Nikasil second less expensive was to press in a steel sleeve which will last longer cause it can be cut 7 times up to 118 and if all you do is open ride and not race this is probably the best way to go..

i don't know if the 100 cylinder fits I'm not a mechanic but i have a feeling if you bore that 85 out to a 100 that will be the first and last time.

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A magnet will stick to Electrofusion.

True. Very Very Softly. On the otherhand the magnet will stick like glue to a iron cylinder sleeve

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The stripping process before a cylinder is replated uses Nitric acid, which will not touch Electrofusion plated cylinders. Nitric acid will dissolve a ferrous surface, but electrofusion requires that the cylinder be bored to remove the finish. Kawasaki has in the past few years gone to a true Nicosil bore.

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The flapper will need to be trimmed back slightly, but it is very easy to do. Or just order the 100 valve. Part# 49116-1158 Tdub

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Ok, one last question lol. Can anyone tell me the difference between the 02 and 03 KX100 cylinders? The 03 is 43 bucks more.

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LOL good cause I ordered the cheaper one! ha thanks for all the help. are you the same fast forward from z400cent?

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i don't know if the 100 cylinder fits I'm not a mechanic but i have a feeling if you bore that 85 out to a 100 that will be the first and last time.

The 100 cylinder does fit, plus there is one more overbore to 105cc.

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The 100 cylinder does fit, plus there is one more overbore to 105cc.

Wiseco offers 2 oversizes for the 100, with the 2mm over making it almost 107cc. Tdub

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