Rebuild Crankshaft?

[Tamean]

Its time for a top end, as it's harder starting when hot, I can jump start it in 1st gear with a half worn rear tire, where before it wouldn't with a brand new tire, and it does pull at low RPMs as good as it did. It's a stock 94' kdx200 except it has a reed spacer and FFW. I don't think the top ends ever been done, but I might be wrong. The crank bearings and seals where done when I rebuilt the tranny 1.5 years ago.

My question is, should I split the cases and rebuild the crank w/new rod and top end ($800), rebuild just the top end ($300), or could it do with just new rings ($100)? My mechanic recommended the full deal because of the bike's age, being worried about the lower rod bearing. If the full package is required, I'll do it, but if not necessary I'd rather spend 100 or 300 compared to 800.

Thanks for your opinions,
Tamean

 

[twocycle]

You or your mechanic should be able to measure and inspect the parts. For example what is the clearance on the connecting rod? The specs are in the factory manual. You can measure and inspect the piston and rings as well.
This will help you determine what needs to be fixed.

 

[MX175]

Personally, I would do the piston and rings (because of age and it is cheap fast and easy) and only do the crank or rod if it is out of spec.

 

[canyncarvr]

re: just rings.

There are specs for the piston, too. Measure it to be sure. Replace it on GP. A '94 would need a LOT of garage time to not need a new piston (at least).

 

[Tamean]

Thanks for the replies, I'll measure everything when I pull it apart after the next enduro in a couple weeks.