Powerband Hit...

[ronluvsurf]

I have an 07 RM125, bought new couple years ago now. I've been mostly trail riding it for two summers now and going on the third summer. Mostly weekend warrior style.

Anyhow, the last couple times riding I noticed that the powerband just doesn't hit like it used to. When it used to hit it was like WOH! ? and the front would come up every time.

now when I rev it up it hits a bit but not at all like it used to, and sometimes it seems like it's not hitting at all when revving out through 2nd, 3rd, and 4th.

It still has pretty good power, just not the hit...any suggestions as far as tuning or is it time to do the top end?

Thanks for any suggestions or comments:thumbsup:

[Uncle Alpo]

Two years without a top end? I'd say it's past due. Clean that exhaust valve while you have the cylinder off; how well it's working contributes to the "hit", too.

[spike00svt]

Just like UA said, sounds like it's time for a top end. This may be a good time to take care of all those other little maintance things that suck to do. Checking or repacking the silencer and cleaning/lube the air filter. It might be time for a new plug and some tranny fluid. Treat her right and she'll do the same for you.

[ronluvsurf]

I've kept the maintenance up pretty good on the bike, always wash it, change fluids, clean air filter & re-oil.

It does need a good once over though, I'm going to take all plastics off and clean them, repack swing arm bearings and wheel bearings, clean the engine and carburetor up, clean up and inspect wheels and brakes, new tires, new hand grips, etc....

But I was wondering if it really needed the top end done yet cause I'm not really racing it or running it all out all the time, mostly single track trails through woods and bit WOT through open sections, probably total of 60-80 hrs total on her...

[ronluvsurf]

maybe more hours...hard to tell though, I rode most every weekend I could from 07

[spike00svt]

You could check the compression. That would give you a definative answer.

[zig06]

Try a new piston and rings, reeds and repacking your silencer.

[Uncle Alpo]

But I was wondering if it really needed the top end done yet cause I'm not really racing it or running it all out all the time, mostly single track trails through woods and bit WOT through open sections, probably total of 60-80 hrs total on her...

A top end is regular, preventative maintenance on a two stroke. Like it or not, these are race bikes and must be maintained for peak performance. You've noticed that the engine doesn't have the "hit" it used to; that's an indication that it's time to dig a little bit.

[mihylo33]

On top of what everyone said, do the top end and your clutch is probably a bit hammered as well.

Good luck!

[shrubitup]

loss of compression from worn rings combined with potentially worn reeds is attributable to physical breakdown of these items - each of which will cause loss of power and snap. If you keep running the same piston after 60 or so hours it could fracture and cause engine failure.$$$ $100 now is preventative maintenance for many long enjoyable rides to come. ?

[ronluvsurf]

Hey thanks for all the comments and suggestions, I figured that it was time for the top end! Amongst a list of other things...I want to get it running well for the next season coming up!

Good Times! Maybe i'll see you guys out there somewhere...im riding in Virginia, Maryland, & West Virginia...

[98rm250_90cr500]

absolutly you should replace you rings like twice a year if your riding that much, rings are cheep and i do my piston once a year regardles becouse pistons and rings were and are alot cheeper than a new cylinder and bover bores suck it will cost you $350 plus for a good bore hone and plating and if you sleve is toaste you looking at around $600 or more i would pay the little cash for the piston and rings any day versus the alternitive i foud out the hard way a few times. and bikes with no power are boring to ride.