94 kdx200 bore and piston question!

Discussion specific to the 1989 - 1994 (E Series) KDX200 model sold in the USA
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Asheron04
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94 kdx200 bore and piston question!

Post by Asheron04 »

So after finding out my kipps valves were out of time and so full of carbon in surprised they weren’t seized or broken...I went out for a ride and it was ripping better than ever. Then all a sudden the ol girl shut off and coasted to a stop. Took the cylinder off about an hour later to find one of the wrist pin retaining clips ground into the side of the cylinder and piston. So I put the digital calipers in the cylinder to find it’s never been bored out so it’s 66mm (plus the nice gouge up the side of the cylinder). I ordered a 68mm wiseco kit and am taking the cylinder into the cnc machine shop I’ve got a contract for some work with to have it bored out. But I’ve been looking at some posts and now I’m confused on wether or not to proceed with the 68mm bore. I

Will this make my kipps valves inoperable? Do I just take them out? Would that make my baby lose some braap? Can I modify the main valve to work and keep the kipps or do I remove the main valve and just use the two secondary valves? Do I even need to worry about the valves at all?

Sorry, I’ve just found a lot of conflicting information. Any help is greatly appreciated!
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KDXGarage
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Re: 94 kdx200 bore and piston question!

Post by KDXGarage »

Hello. Welcome to kdxrider.net.

Sorry to hear of the trouble.

If the cylinder is in stock form, then it had a coating on it from Kawasaki (Electrofusion). This very thin and very hard coating can not be bored or honed. Your best option is to mail the cylinder to Millenium Technologies or PowerSeal USA to have them strip the stock coating and apply a new coating. They can also sell you a 66 mm stock sized piston.

The stock cylinder is not sleeved. One can not just bore it to a larger size. A sleeve is worse than a plated cylinder for heat transfer, reliability, etc. If someone has a sleeve in a 1989 - 1994 cylinder, then it can be bored larger. The KIPS WILL NOT WORK with a bored sleeve. There just isn't enough room for them to work. YES, that will remove performance.

Again, mail it off for replating and a new piston. Try to get a refund for the 68 mm piston and skip the local machine shop.

Good luck.
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Asheron04
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Re: 94 kdx200 bore and piston question!

Post by Asheron04 »

Thanks for the info...glad I Asked before doing anything else! Is there a preference between the two shops you suggested, Price/quality/time wise? Thanks again KDXGarage, you rock!
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Re: 94 kdx200 bore and piston question!

Post by KDXGarage »

You're welcome. I have heard good things from both places. One might have a faster turnaround time than the other whenever someone checks. There are a few people on here that have had work done this year. Check through some past threads. Some have great pics to show what it looks like afterwards.
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