Cylinder gouges

[Rosscw3]

2000 RM125. Lost the bottom end and now have several gouges on the cylinder walls (needle bearings bouncing around). Can they be filled-in and have the cylinder replated or should I buy a new cylinder?

 

[jmics19067]

you have a host of options available

buy new -expensive
have it bored and put a steel sleeve in it - heat disapation and the longevity of the sleeve are suspect

have it welded rebored to a stock size and plated cheaper and /or longer wearing than the first two options

have it overbored and replated witha bigger piston fitted possibley cheaper than having it welded and rebored plus more displacement more power. this would be the option I would seriosly look at.

 

[Rosscw3]

Thanks,

Buying new is expensive. the only places I can find is midwestcycle and bikebandit.

I hear and read that Eric Gorrs place can do amazing things.

Dont think I want to overbore. The bike is used for woods and light MX riding. I hear overbores require even more frequent maintenance.

I'm thinking Ill send it to Eric and have him take a look at it.

 

[DEANSFASTWAY]

Yeah and youll get more bottom /mid power . Most of the time when I build a bigger bore 125 I like to use a Yamaha type top bearing as it is 2mms wider than a Honda type and spreads the load better. 58mm 4mm oversize piston needs the cases opened up in the front a bit for clearance so dont assemble the bottom end before you decide what to build .

 

[steve talley]

Just had the same done to my 99rm125. they welded the damage area and overbored now it runs better than a new one. :thumb: