Bottom end rebuild

['00kx250spode]

I see alot of posts about how often a top-end rebuild should be done - but I don't believe I've ever seen one about the bottom end.

So I ask you, how often should the bottom end be rebuilt? I had Eric punch my 2000 KX250 out to a 310 and I've started worrying that I should of have Jim rebuild the bottom while I was at it.

Of course, I want to wait now until I've got a good fill of riding in on the 310. A bad cold has kept me from the track all week. :think

One more related question while I've got you here. What does it do to have the engine blueprinted and the cases matched? And does that affect performance? Who does that kind of work: Eric or Jim (2FastRacing)? Okay, I know that's more than one question. :D

 

['00kx250spode]

Anybody have advice concerning the bottom end rebuild schedule or blueprinting/case matching for performance?

Anybody out there? :confused:

Come on, I know I've seen dumber questions than this! :scream:

 

[KawieKX125]

On a 250, i would say 2 to 3 years with a decent amount of riding time will sufficce between crank refreshenings. Jim does awesome work. I had him rebuild a crank and he was nice, fast, and did his work quickly.
On a 125 that is revved alot, one year is what I would recommend. I have had to do yearly cranks on my last 2 KX's because they decide to grenade on me one year after I start riding them.
Blueprinting makes the engine perform the was it is supposed to. They cases are matchd to the cylindr, the gears are polished and the shift mechanism is modified. I never thought this was worht it, but after riding my new bike with case work, I can tell you it is worth it. The bike shifts under full power with no clutch and I guess that is is making as much power as it possible can for a stock bore KX.

If you have the money and feel that your bike needs it, go for it.
Just my opinion and ramblings though.

BTW, Eric does the cylinders and Jim works with him to do the cases. Good team IMO.

 

['00kx250spode]

Thanks (again) Kawie!