'99 KX250 Rehab (Budget Rebuild)

[ecdeyzel]

Umm, I totally meant to say cast. Thanks Foxx. I measured the piston just above the bottom of the skirt where the shop manual indicates and it measured at 66.3mm on my vernier (unfortunately the only good measuring tool I own). Soo it seems to be stock to me. Will I be safe if I order a stock spec ProX piston kit?

Are the score marks on the side the results of piston slap?

Busy is good, but five 11 hour work days is next level! HAHA! Good to hear you are well compensated. You should go rip up some tracks every Friday, Saturday and Sunday morning just to even things out. 

[Foxx4Beaver]

you should check what the cylinder bore measures, high and low....and try to determine what your current piston to cylinder wall clearances are, along with your current ring end gap, before buying a top end kit, just yet.

I know this a budget build, but if the clearances are too great, there's a chance you may have to re-plate the cylinder....if you can't get a correct size from ProX...though I'm pretty sure ProX go in 1/2mm increments, so there's also chance you may "not" have to do anything with the cylinder.   

[ecdeyzel]

you should check what the cylinder bore measures, high and low....and try to determine what your current piston to cylinder wall clearances are, along with your current ring end gap, before buying a top end kit, just yet.

I know this a budget build, but if the clearances are too great, there's a chance you may have to re-plate the cylinder....if you can't get a correct size from ProX...though I'm pretty sure ProX go in 1/2mm increments, so there's also chance you may "not" have to do anything with the cylinder.   

Haha, I think the term "budget build" can officially be used very loosely for my beloved KX. Although budget means different things to different people. For me I wanted to get it rebuilt quickly, but realised I have worked too hard on it to rush the rest and would rather do it properly (or as properly as my wallet will allow for now).

I found a shop that will do the measuring for me. I have a set of feeler gauges at home that I will measure the ring end gap with. I will keep you posted once I have the needed info.