Where to get jug repaired and replated?!

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#1
I made a really bonehead mistake of putting the piston in backwards when rebuilding my 97 RM250. It didn't help that the arrow on top of the piston was worn off (and I really did not know about the design of the piston then...........I do now though). On top of that, the exploded diagram of the cylinder and it's parts (in the manual) shows the piston backwards in the picture!?!!?!?!?!? WTF?

So, the bike ran decent considering the piston was backwards, but didn't have good top end power. We tinkered with the power valve until discovering in the actual polaroid pictures in the manual that we put the piston in backwards.

When we took the jug off.....we found the damage though. The ring gaps snagged the exhaust port on the power stroke and popped a chunk off the piston. The chunk appears to have passed out the exhaust (no scoring down the side of the piston/wall and crank moves freely + no chunks in oil).........but it left a gouge in the cylinder.

The powervalve that sticks into the exhaust port has a very very tiny scrape....probably nothing. But around the edge of the exhaust port is a chunk of the cylinder wall gone. Its about the size of a pencil eraser and as deep as the width of a finder nail.

So what can I do now? I'm looking for the least costly fix. Can that spot be welded or coated over (or both). Who does the most reasonably priced work? OF course I also need a new piston, wrist pin/bearing, and rings.

Thanks for the help and don't beat me up too much...I already did that to myself.

Micah
 
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#3
Well, I checked his pricing, and if I'm not mistaken, it looks like about $450 will take care of a big bore and all the fixins. So I'll most likely go that route. I'm pretty sure the gouge can be bored out and won't require welding.

Although, he's not local enough to drive (3 hours from me), but he is local enough that I'll most likely get hit with a sales tax :(

Micah
 
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#4
He did my 98 RM250 . I got the 265 kit and the mo-better everywhere job.
It changed the power band of the bike. It doesn't have a hit any where. And all of the power is on the bottom end. But the bike is real smooth, and easy to ride , and doesn't fatique you out. So it is worth the money, for off road riding. He took almost 8 weeks to do it .....but he did it right. He gets quite a bit of business.

good luck
 

RM_guy

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#5
You can go directly to US Chrome and they may be able to repair it with out having to bore it out.
 
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#6
I used LA Sleeve a couple years ago with great results,got a friend who used US Chrome,he's very happy too.
Don't feel bad,we've all done silly stuff. I didn't properly install a circlip,and many other classics in the past.I guess the good thing is we seldom repeat the same mistake.at least I hope ! Doug
 
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#7
Now I have to rethink things.

Greaser....I'm not so sure that I would be happy with my RM if it had those manners. Currently it is....was....really really snappy. It felt very torquey which was just awesome for woods riding. Top end was no pooch either, but it wasn't the fastest. It could put up a good fight with my friends YZ426

My only complaint was that it needed a 6th gear.

So when I rebuild it I would like to restore the power to how it was. I would take more top and bottom end, but I would hate to see that snap go away in favor of a smoother transition.

So I'm considering just replating and going with the standard piston again.

RM Guy, I hopped on US Chrome's website. The only pricing I found was a $60 fee to weld and bore if gouges are too deep in the cylinder. Do you know what they charge approx. for a replating job? I would think it's fairly cheap if Eric Gorr can afford to do all that machine work + new piston/rings/wrist pin + the plating.

Micah
 

RM_guy

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#8
You may have to call. I can't find the price either. I had my cylinder done a few years a go and it was $150. I think I remember hearing that it was $165 now but call to make sure. You may want to call anyway to make sure that the damage that you have can be effectively repaired.
 

Chili

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#9
We just had my son's KX80 Done by US Chrome and it looks to be a top notch job. Our race mechanic sends all his stuff to them even though it means shipping it out and dealing with getting the stuff back and forth across the border even though we have a local shop here that does the work.

As for the manners of the Big Bore, talk to Eric he can set that motor up with many types of power characteristics.