250-500cc New piston, scratched. Cylinder also.

The piston looks good the damage to the head was probably before this piston, the head looks bad you can get it machined on a lathe to re profile check squish too an get it done at same time, most good machinists will only charge small fee for this.
With the head off if you push piston from tdc is it smooth alL the way through if not take barrel off check conrod as this probably would not of been changed when the piston was and will cause noisy running and possible grenade the bottom end. But that is an IF

It was smooth.
Desided on just keep using cylinder, if it getts worse ill send it in for repair. I used worse cylinder on smaller engines, so gonna go with my gut on this one. :-P
Scratces on the skirt of the piston will not damage the cyl in the short run if the construction is in ok shape?
Think im gonna buy new top on ebay, most of them dosent cost that much from uk. Just a tip, looks like ebay is the place if you want a new head.
How will a cr-head work on a wr? Just curious.
One last questin, then i think i got all the help i need.
What do you think abut the compression i messured, its ok, on the low side or very low.

And again. Thanks for your help guys, even tho i may ask stupid questions just to get second opinions. :-D

MY head looks 100x worse than that....looks like it was hit with a ball peen hammer 1000x....but It ran freaking awesomeone when I broke it down so i just slapped new o rings on the head and copper washers and shes going to run for awhile.

Maybe one day I will get some extra $$$ to replace the clutch and send it to zip ty or somewhere for a full go on the porting and all that jazz. But for now, its a 900$ dirt bike lets ride

Haha, well if its 100x worse then its bad.
Well, mine is still going strong. Havent change anything yet..
But have a few questions.
I'm litle curious, is it possible that a new head will affect the engine in any way?

Whats cons and pros when it comes to forged and cast pistons?
I have a wossner now, if im not wrong they are forged?
Is wossner a good brand, i see they are not the cheapest. ProX are cheaper, but they are cast?
I like the price on the proX.. And looks like if im gonna buy a piston local, most of them sell proX...
Any tips?

I'm also wondering, do you guys grease the top of the reardamper. Im thinking about where its connected to the frame. Dont know if the last owner that fixed this bike have done this, but i doubt it. He hadnt put grease on all the places at the bottom, so iv done that now.. Damper is litle smoother now, even tho it was fine before i did this.

If the head is completly shot then a small gain in performance may be noticed but i dont think us mear mortals will feel it more likly see a gain in mpg, unless you raise the compression ratio.

Wossner are very good but i see more people have issues with ring gap with them than any other brand so check n re check.
Forged vs cast swings n roundabouts most think forged are stonger less cavitation possability in forged lighter etc. truth is if its a good brand like jap pro X then there really isnt much in it (slate me now).

The spherical bearing at top of damper sure i grease that with waterproof putoline, i grease anything thats supposed to move apart from cables and throttle housing etc thats dry.