03 KX85 cylinder repair

Im working on a 03 KX85 for my nephew and the top end is shot mostly due to the picture below. My question is"where is the best place to send the cylinder off and have it worked and replated? Will I need to send the power valve in with it or remove it?" Im good with 4 strokes but this is my first 2 stroke top end rebuild and ive never had to send off a cylinder to get replated. Any help is greatly appreciated.

Heres the pic


Langcourt, Millenium, etc.


These people are very reasonable and have a quick turnaround and due excellent work. And you will get charged less if you disassemble the power valve and remove studs. Check the site and they will give a price breakdown and if it's shot they have replacements.

Thanks for the tip on the stud and power valve removal, thats a $45 tip lol.

Powerseal USA did my kdx200 cylinder...flawless work, nikasil plating is very strong compared to electrofusion

Heres the pic



I got news for ya, the top-end ain't the only thing that's shot if he was running it with that (non-existent) filter. That engine needs a crank too. And the kid needs a slap.

I agree with you on that chokey....they purchased the bike knowing it needed a top end for 750. I told them what it would cost to rebuild the top and bottom I priced every thing and it was $367, that is new everything including a water pump rebuild. That doesnt include the cost of cylinder repair which im guessing will be 200+ maybe with shipping. Im not charging anything to do the work. They said do a top end only. Here are some video of the rod and crank play and some photos of the cylinder. Watch "KX85 wrist pin play" on YouTube

KX85 wrist pin play:

Watch "KX85 conecting rod play" on YouTube

KX85 conecting rod play:

Here are pics of the cylinder



Im concerned that the bottom end might give trouble after while I know it ate what is missing from the filter.....I dont want it blowing up on the kid hes 9 and used some of his money to help buy it and hes really excited about it. He is coming off of a kx65.

 They said do a top end only. 



Tell them no. I wouldn't in good conscience be able to do that knowing I was giving them back a grenade to ride.


Advise them that they are going to spend $350 to put in a new piston and replated cylinder, and then the crank is going to let go and destroy those new parts, forcing them to replace those new parts again AND do the crank like they should have to start with.

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