When to do top end? 01 426

[Paewraul]

How do you know when to do a top end? She runs fine and strong, but it seems like bikes with much less time have had theirs done already. Gonna do valves soon so is there something to look for? Any other tell-tale signs? Will she run different?

Never got into the engine before, so...

Hard to do?

Ballpark cost?

Good, non-oem parts to consider?

Thanks for the input.

Jeff

[wes_scooter]

how oftain u do major engine work is really a matter of how u ride it...ur maintnance schedual, and things like that...as to the difficulty, its not bad expessuly if u have ur manual...other wise just ask questions here...if ur going to do the head work u mite as well plan on refreshing the cylinder while ur in there. i'm not sure wether they have a nikisil liner or not, but eather way i'd do it all if i'm going to all that work. just my 2c worth

[Paewraul]

Its a SM now, and I ride her a bunch around town. Backroads, some highway, some trails sometime. I bet I'm close to a couple hundred miles a month, maybe more.

[Birdy426]

As far as the piston and bore, mine was ready for a refresh of the piston and rings at about 4000 miles (bore was still in spec, just did rings and piston), and a new tbig bore kit at about 7K (the cylinder was worn out of limits at the bottom). The big end bearing and mains still felt good, though I replaced the crank at 7k as well because the splines on the primary drive side were worn. A good rule of thumb is if the valves "move" out of limits twice in a short period of time, it's time to replace them and grind the seats. As far as cost, it was about 1600 bucks for everything...new crank, new big bore kit, 5 new valves with springs, retainers and keepers, grinding the valve seats and cleaning up the ports, gaskets, etc.

[Paewraul]

Thanks Birdy. did you do the work yourself?