scratch in bore

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adrien222
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scratch in bore

Post by adrien222 »

my kdx 125 has a scratch in the bore... it is just on top of the exhaust port and it is vertical... and little maybe 0.5mm or less deep... how bad is that? and what can i do other than boring oversize?

also can it continue to run that way? as there is actually no piston movement sideways. also i am in the caribbean so boring oversize isn't available here unless of course there are other ways to do it. thank you for your timely response :-)
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rbates9
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Post by rbates9 »

Pictures help a lot with stuff like this.

I'm not familiar with the 125 but I would assume that it is a plated cylinder so you would have to over bore it and put a sleeve in it.

The better option would be to have it replated back to stock spec if it is bad enough to worry about. Can you catch your finger nail in the groove?
adrien222
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Post by adrien222 »

i definitely can catch my finger nail and probably break it as well :-( its not that deep though. but yes my fingernail can be caught quite easily.

i believe it is plated as well.

so are these the only options?
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fuzzy
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Post by fuzzy »

that it is a plated cylinder so you would have to over bore it and put a sleeve in it.
The best solution is to send to a replater with a new piston...They will bore the plating out/replate/get clearance right.

If your scratch didn't go through to the bare aluminum (IE just a light scratch in the plating) I wouldn't worry about it for the time being.
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
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adrien222
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Post by adrien222 »

checked out the scratch this morning... it seems for the most part to have only scratched the plating so... i think it will hold out for now. but again in the caribbean no one currently does this and i would much rather send it to replate or oversize.
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Post by Fletch »

Millenium tech and cvtech aab (in Canada I used them and they were awesome) both offer exchanges where you order a cylinder they already have and then send yours when you have the new one. Worth emailing them to see if your core is good. This way you have almost no downtime. IF they have a 125 cylinder.......
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adrien222
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Post by adrien222 »

i'm looking for a way to do it on the cheap... as well checked out the cylinder this morning. on two sections of the exhaust the plating went to the aluminum wall of the cylinder... what are the repercussions of running the engine like this?
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scheckaet
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Post by scheckaet »

catastrophic failure.
destroyed top end, rod, bearing...
Have it REPLATED.
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Post by Fletch »

It Happened to me, cost about 700 to fix it all after the blow up. I could have saved hundreds
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adrien222
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Post by adrien222 »

sucks... i am in the caribbean where no one does this... what is the most less expense way i can replate this cylinder?
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Post by Fletch »

What year of 125?
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adrien222
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Post by adrien222 »

not quite sure... it has to be between - 1991- 1994 :-) how can i find out?
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Post by Fletch »

is it liquid cooled?
Vin number should tell you the year, but you'll have to decode it.
I'm asking cause I was looking on ebay for you to see if there is one there that is useable.
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adrien222
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Post by adrien222 »

it is water cooled... how on earth do you decode that vin number? all i have access to is the chasis and engine number
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Julien D
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Post by Julien D »

no number stamped on the steering head?
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Post by Fletch »

Is there a vin on the head tube?
I didn't even know they made a 125 liquid kdx, I wonder if a kx jug would work?????
Anyone?
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adrien222
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Post by adrien222 »

i'm not sure if this bike has ever been in america... wouldn't it have to first be assigned a vin number? is the steering head the handle bar? i'm wondering about the kx cylinder as well they look like similar creatures :-)
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Post by Fletch »

Yes that's definitely worth investigating. kx with lights a kdx???
The Head tube is where the steering stem goes through, behind the headlight
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adrien222
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Post by adrien222 »

there is a little black plate there with chasis number and bike type... and it does say start with dx125... which is the kdx. so as well.. so the bike being run this way even though the plating is very lightly peeled it's like 2, 2mm spots. is very dangerous and expensive to repair right
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Post by Fletch »

The trouble is that since the plating is peeled you have excessive cylinder piston clearance. THat means the piston can rock inside the cylinder more than it should and cause strain and cracking on your piston skirts. They can eventually fail (like mine did ) and throw a bunch of aluminum in your crank case. You can also break the case if this happens (I did) and then your in for way more than just a replate and piston kit.

If you HAVE to run it then do it but don't rev the piss out of it and warm it up good. But my advice is to replate and new wiseco piston and then your good for years and years and years
Fletch
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