Top end redon, but....

I've just had my top end done to my 400exc, everything but the head. I thought that the bike would feel, almost, brand new and it really doesn't. I've never had a top end done before and I'm not sure what to expect.

I putted around yard for the first ride, it didn't sound exactly right. The exhaust sounded :) poofy, and it even coughed/poofed once while riding it and then picked up and kept going. Yep, I warmed it up rode it easy and cooled it down. I hit the trails a couple of days later. It sounded ok and never coughed. I didn't have any problems on the trail but I thought it would have more umph. So I'm wondering if this is all normal. ??

Thanks in advance


Sure, it's pretty normal. Sounds like you did the topend before it was too badly worn, which is a good idea.

Thanks Jeb,

That eases my mind.


What did they actually do in this topend rebuild ? I would hope a hone job with rings and a re-grind on valve seats as well as new valves. I just did mine and after riding it and letting it cool down 4-5 times to seat the valves i noticed a difference.

"I've just had my top end done to my 400 EXC, everything except the head."

Hopefully you checked the valves and valve seats, or at the very least checked the valve to seat seal with fluid poured into the intake tract while the head was on the bench. Pistons and rings usually have a longer running life span than valves.

What did they actually do in this topend rebuild ?

Piston, intake valves, rebuild waterpump, cam bearings, honed cylinder and cut valve seats along with replacing all necessary seals, links, shims, orings and gaskets to get the job done.


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