So i recently purchased a blown up 2001 kx85 for next to nothing and i was told the top end blew. Tore it down and found that the connecting rod bearing blew so it was seized in the crank not in the cylinder, piston was still trashed since some metal flakes/bearing remenants got up in there. I ordered a full bottom end rebuild kit with crankshaft and a piston kit. But my main concern is the cylinder, it looks usable and i was excited until i seen this little knick in one of the reed ports, it is very tiny but my concern is if i use it as is i dont want my over $500 parts order go out the window due to a ring catching ect. I hope someone on here can tell me if this is a big issue or if it looks alright, thanks in advance
85 KX85 cylinder still usable??
- Thread starter JohnWayne007
- Start date
Is it a gouge, and is it "below" the ring at the bottom of the stroke?
it could cause a problem, but I'm guessing it may have been caused by a ball hone catching the plating during a past top end rebuild, as I don't see any scoring above or below the chip. It's also at the very bottom of the ring travel so that works in your favor. I think you could run it as is without any problem, or for piece of mind you could do a wear check after 5 or 10 hours on the rebuild, and of course option 3 is to just throw 250 or so at a replated cylinder. If it was me I'd do option A and possibly B.
That is what i was hoping for, i figured it was probably below the ring travel but i wasn't 100% sure or not. But i believe it was from a peice of metal as i actually pulled a tiny little chunk that was stuck in it out. Would i be able to get away with using a dremel and rounding the corner of the port out enough to get rid of it and doing the same on the other port to match? Or would that just be over kill. I have a dremel and all the right tips to do it i just didn't want to go for it and find out it would make things worse or mess somthing up.
It is almost like a dent more than anything
If you are very carefull, the dremel could help, I would use carbide tips though, not a stone as that may chip it worse.but I still think you can run her as is.
I think i will try with the dremel for an ease of mind so i know it wont catch on it. Im somewhat of a perfectionist and when i put things together i like knowing that there are no flaws internally. I would just buy a new OEM Cylinder but thats just an extra $300-$400 on top of rebuilding the complete bottom end. This wont be used for racing, mainly trail and field but i would like it to last. I had purchased the Hot Rods complete bottom end rebuild kit and a Wiseco complete top end rebuild kit. I was advised to stay away from the wiseco crank kit due to alot of people having them blow up within a handful of hours.
I've never used Wiseco cranks, but have had good luck with hot rods cranks. Let us know how she turns out.....by the way, keep in mind the crank seals may not be OEM on the hot rods crank, make sure you record the part numbers off the seals for future reference. I ran into this on my RM.
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Dremel is overkill imo. I would get a magnifying glass or jewel loop and fine grit paper to remove any burrs.
1 no way ring comes down that far.
2 matching dent? Lol! It's a 2 stroke
What did the old piston look like?
Did you mic the bore or at least check the ring gap?
1 no way ring comes down that far.
2 matching dent? Lol! It's a 2 stroke
What did the old piston look like?
Did you mic the bore or at least check the ring gap?
And there's yer sign, either you is or you isn't.
No i wouldent match the dent. I would trim off enough around the side of the port where the dent is with a dremel to remove it completely.
The old piston was no good due to the rings being stuck to it (fully closed ring gap on piston) so there was no point in checking it other than that the piston was fine but not usable. once my order arrives i plan on checking everything out
The old piston was no good due to the rings being stuck to it (fully closed ring gap on piston) so there was no point in checking it other than that the piston was fine but not usable. once my order arrives i plan on checking everything out
The cylinder looks worn, but the dented section wouldn't give me a second thought other than to smooth it out a little. use anything you want for that. rub some light grease on it if you have no machinist's dye to see if it will leave a mark. Unless someone was powering a ball hone with an outboard motor I would guess that it was a poorly fitted 3 finger hone. I did notice that the entire length of the cylinder has been honed. Gotta make sure that the skirts have a nice surface to seat on you know!
Well i am feeling a little down on my luck. I did a thorough look through at my cylinder and not sure exactly how i missed it the first time, im assuming due to lighting but i found this on the cylinder wall. It feels a little rough, i cant really catch a fingernail on it but it just seems like somthing a ring could catch on? I took care of the little dent that was my first concern.
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Doesn't look any worse than what I've run before, as long as you catch it with your fingernail or a pic I'd run it without a thought.
I might just be over concerned, i mess around more on 4 strokes with a straight cylinder with no ports and all that cut into it so when i see stuff like that i tend to over think it alot. I cant catch a nail or pick on it but i can feel it if i run my finger over it, it feels like a smooth hump. But the rings dont catch on the open ports in a 2 stroke so im sure this would probably be fine. Just hate to see $500 go down the drain but also dont want to spend another few hundred on a jug either lol
I would be on the safe side if that was a resale bike and get the jug redone. If it's for yourself/family than run it. worst could happen is you need a new top end sooner than later. There is a company that puts their name on it for other countries called Langcourt. I use them exclusively in Alabama and have not had bad success. Other opinions will very.