Tore the motor apart in my bike and the valve broke in half and was bangin around in the cylinder. No cylinder wall damage but the top of the piston has some dents. It’s not cracked or anything, can I put a new head on it and go or should I replace the piston and rod? It’s $1000 difference between a used motor vs a used head, you can see why I’m asking, lol.
if you know for sure that it is ONLY a little indentation on the piston, you should be fine. the only problem is that it’s hard to tell for sure esp without taking the piston out. you never know if there is some hairline fracture or something. do a leak down as well
1300 bucks… bam… sell the old block for 500 on ebay with all the shit thats on the motor and be DONE with it for 800 bucks… orrr build the old one for next season… bore it over .602 so you can have a zx-16r… (like you always wanted)
If I don’t need a new bottom end I’d rather not buy one. I’d like to just pick up a used head and throw some cams/springs/retainers in it with a thin head gasket and be done w it.
word… whats caused it? theres pistons on ebay too 
just in case.
looks like a broken valve retainer caused it. i might buy used pistons/rods and a used head and go that route. should be around $400 then another $600 or so for race cams etc etc. thats gonna be my best bet i think.
So it wasn’t those metal shavings we left in the cylinders after we drilled out the screws on the secondary butterfly rod? haha
In my opinion I would go with whatever best suits your plans for the future, this bike was obviously not babied as we all know the previous owner used it to it’s full capabilities, so while replacing the head may be cheaper, you may run into problems down the road that are unforeseen.
I think since I’m in it I’ll throw in used pistons and rods to make sure theres nothing going on. maybe some lower compression pistons and nitrous lol. i’ll dig into it more tonight and see how the rod bearings are. i still like those sneaky pete 1lb nitrous kits…