Damaged cylinder wall

[IDAHOSPUD]

Found a problem
Ive been doing the RB head mod to my ec300, just got the part back from RB-designs. I decided to put new rings in the bike as i had it torn down this far, might as well . . . . . .
Anyway, i remove the cylinder from the engine. I go to take the cir-clip off the side of the piston and its missing from one side, and the piston pin has been moving and gouging up the side of cylinder wall.
Glad i caught it before a catastrophic event deep into the Idaho wilderness. but this wont be cheap to fix either. Funny never felt like there was anything wrong with the motor, kind of down on power, but not terrible. so my questions are.

- How does one know if the cylinder can be fixed and replated?

- Is that the best way to go, if it is fixable?

- looked everywhere cannot find missing clip, could it have passed out without doing anything? missing from the factory?

Already talked to gofasters about a S3 cylinder, might be an option if fixing is not possible. more money then i wanted to spend.

Any advice would be great. thanks

[gasgasman]

I don't think the circlip was ever installed.
If it came out of the piston, it would sieze between the piston and the cylinder wall.

Most gouges can be filled in with a welder, then bored and replated.

[twowheels]

Try a reputable company like Millenium. They'll strip the cylinder, inspect it, weld it, bore it, and replate it and you'll be none the worse for wear (a few dollars excepted).

Sounds like somebody forgot a circlip when building the motor ...

Originally Posted by IDAHOSPUD

Found a problem
Ive been doing the RB head mod to my ec300, just got the part back from RB-designs. I decided to put new rings in the bike as i had it torn down this far, might as well . . . . . .
Anyway, i remove the cylinder from the engine. I go to take the cir-clip off the side of the piston and its missing from one side, and the piston pin has been moving and gouging up the side of cylinder wall.
Glad i caught it before a catastrophic event deep into the Idaho wilderness. but this wont be cheap to fix either. Funny never felt like there was anything wrong with the motor, kind of down on power, but not terrible. so my questions are.

- How does one know if the cylinder can be fixed and replated?

- Is that the best way to go, if it is fixable?

- looked everywhere cannot find missing clip, could it have passed out without doing anything? missing from the factory?

Already talked to gofasters about a S3 cylinder, might be an option if fixing is not possible. more money then i wanted to spend.

Any advice would be great. thanks

[Zman]

You know what they say about lemons and lemonade..... Now is the perfect time for a big bore kit! I had Eric Gorr punch out my 2001 XC300 to 327cc with a 76mm ATC250 bigbore piston. It has worked flawlessly since he built it approx 7 yrs ago. I would highly recommend getting it done if you want more power across the power band and especially if you ride at higher altitudes. Eric is working with or within Millennium now. http://www.eric-gorr.com/

[GMP]

I got a quote from Power Seal (PA) on a cyl that needed a cracked and chipped exhaust port roof welded, reshaped and replated. $300, and it was more complex than just a simple gouge repair. I'd just do this and keep it stock 300cc. Plenty of power with a fresh top and head mod, and reliable.

[Zman]

IMO, the price is going to be similar either way, whether he welds the hole, bores and replates the cylinder or just has it bored and plated for the big bore kit. He needs similar parts either way. The main difference is the use of the big bore piston kit which costs similar to stock parts. I am 6'4", 250lbs with riding gear and backpack, I ride high altitude periodically and honestly I found the stock 300 lacking power. I realize big bore kits are not for everyone, but the one Eric Gorr built for me fully addressed my needs and has been ultra reliable.

[IDAHOSPUD]

My local shop looked at it, says it can fixed no prob, so i am shipping it off once the piston gets here. would consider the big bore but i already bought the piston so that would waste some cash. At least its not a 650 dollar project. thanks for the input all.