newbie here with some newbie questions
- Thread starter supa200
- Start date
I pulled it apart today and the cylinder walls look really good ,no scaring or scratches but the piston looks ''burnt'' on one side?....it says 200 on the top and on the inside it says ---ART with a S under art and on the other side --37101 MADE IN JAPAN---any ideas? if the walls look good ?
u sure it doesnt say 2.00 on the top? possibly meaning 2mm oversize from stock? have you got some calipers that you can measure the piston with? i think 66mm is stock. even just a metric ruler?
it doesnt matter what the piston size is....u need to be measuring bore so if the calipers in the bore measure 68 then it is 68 mm which is 2.00 mm over bore or 80 thousandths over.....the piston is gonna measure smaller than the bore always thats y it has rings! if the bore of the cylinder measures 68 then u need a 68mm (2mm Over stock) piston kit as long as the jug doesnt need machined.
i worded that kinda wrong....it does matter what size the piston is but just bc u measured the piston at 67mm doent mean thats what the bore is.....the piston will be sold at the bore size not the physical size of the piston....if you are sure the jug doesnt need machined then buy the piston and rings and a gasket set and while you have it appart have it honed so the rings seat well....its like 10 dollars at napa and then u should be good, if you are unsure take it to a machine shop and ask b4 you buy the piston! but yeah if you wanna go with a cheap piston you can buy namura kits in ebay with gaskets and all for like 75 or 80 dollars
so a .80 is just about tapped out isnt it? should I just buy a .90 and just have it bored to be on the safe side?I took it to the machine shop and the jackass there was to busy for me,its the only one close to me,he just said buy the piston make sure its big enough and he would bore it out for me...
See thats poor business practice on his part in my opinion! it would only take him 2 min to look at that cylinder and tell you if it needed bored....but anyways if you buy a .80 and it doesnt bored then you could put it back together and ride....they do sell .90 pistons, i have never bored one of mine out that big....that makes the sleeve walls really thin and i have always worried about heat problems going that big so i have always stopped at .80 and replaced the jug after that! but .90 is the MAX on a blasty jug. so anyways yes you could buy a .90 and have it bored but i dont know how long they will run reliably when you go that far out maybe someone else on here could advise you on that.....i just bought a used stock bore jug on ebay last week shipped for 70 dollars ready to bolt on so may wanna do some searchin!
