Oh yeah that was an old piston from and older incarnation of the bike that was was horrid (me not having a clue what I was doing) that i had knocking around.
Got it all together yesterday.
Left the piston alone..
Widened intake ports by about 2mm either side
Widened exhaust by about 3mm either side then raised by about 1mm
Polished the exhaust pot the best I could
Fuck me... it's so much better than before.
Loads more torque / general power throughout.
Bike is tomos a35
mlm 15 intake
Sha 15 clone
1st Gear Jammer clutch with light springs
Wish I'd done this ages ago now.