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What brand piston works best for a 1993 kdx 200. The cylinder has 3000 miles(according to odo). I had a professional inspect the cylinder and he said the cylinder was in good condition but not the greatest. He ordered a pro-x piston. We have had two of the pistons with the same problem. On both pistons the top groove was to narrow for the ring to fit into. Bottom groove was OK. He said he would NOT put in a wiseco. Can someone give me some kdx magic info on what the proper brand of piston would be?

WISECO!

doctord23 wrote:WISECO!

+1.................why did your mechanic say to NOT run a wiseco??? thats all i will run in my bikes. never had a problem.

pro-x pistons for kdx200 are just fine. Wiseco is arguably better. Lots of mechanics who have been in the business for a long time will not use a wiseco. Wiseco used to have the nickname "seizeco", but they have improved their product by leaps and bounds over the years. Many people still have a bad feeling about them though.

FWIW, I would be comfortable running either piston in a 200. If there is some problem fitting rings on the pro-x, I would suspect the wrong rings were ordered. I've had my hands on many pro-x pistons, and never seen that.

juliend wrote:pro-x pistons for kdx200 are just fine. Wiseco is arguably better. Lots of mechanics who have been in the business for a long time will not use a wiseco. Wiseco used to have the nickname "seizeco", but they have improved their product by leaps and bounds over the years. Many people still have a bad feeling about them though.

FWIW, I would be comfortable running either piston in a 200. If there is some problem fitting rings on the pro-x, I would suspect the wrong rings were ordered. I've had my hands on many pro-x pistons, and never seen that.

apparently the regional dealer rep hasn't either. How much wear can the cylinder on these bikes take? It's a 1993, is my only option a total replacement on the cylinder if it is out of round?

why would it be out of round?
they can be replated if the coating is gone, check powerseal, they did mine and had a good result.
STAY AWAY FROM US CHROME.

I used langcourt for a re-plate and was very happy. I have also had a couple cylinders done by millenium and they did a good job. Powerseal also has a great rep, as scheckaet mentioned. I can't remember off hand what the service limit is on the bore, but it is in your service manual if you have one. If not, get one!

I find good deals on wiseco and prox pistons online. Ebay usually! The piston was the same from 86 - 2006, so finding one should not be a problem. Sounds like your dealer has a few screws loose?

J.

Run ProX pistons in both mine...absolutely no problems...and inexpensive for the set on E-Bay.

Bad idea in your 220. You should take the pro-x out asap and install a wiseco. Sooner or later it's gonna bite you!

The OEM/Pro-x for 200 is fine, but the 220 piston was poorly designed. The skirts are apparantly weak and prone to breaking.

juliend wrote:Bad idea in your 220. You should take the pro-x out asap and install a wiseco. Sooner or later it's gonna bite you!

The OEM/Pro-x The skirts are apparantly weak and prone to breaking.

thats what ive heard about all pro-x pistons. aint pro-x just an ole cast pistons? what happens to cast pistons? they are weak and break ....believe me, i have a whole shitload of cast pistons{broke} that i have pulled out of bikes,cars over the years......
the forged piston is the only way to go imo. the new weisco is lighter, stronger and really not that bad priced.

juliend wrote:Bad idea in your 220. You should take the pro-x out asap and install a wiseco. Sooner or later it's gonna bite you!

The OEM/Pro-x for 200 is fine, but the 220 piston was poorly designed. The skirts are apparantly weak and prone to breaking.

Thanks for the heads up! The 250 really doesnt get used much,now that I have the 220.....and I will make that swap after this weekends race! cross your fingers for me...but its too late for me to get parts before sunday......it will only be the third ride with the prox so I hope it can handle 2 and a half hours more!

Nothing wrong with a cast piston, but I'd take the wiseco. Now, on the 220 there is something wrong with Pro-x's casting, and they need to cease making them. Note the wiseco is like an "F" in micro-sized ratings like pro-x offers. Basically the clearance will be on the tightest side of spec, plus it's a forged piston, so WARM IT UP before riding it....This is how wiseco got the name siezeco. Watched so many people go flog a cold bike.