ya i think so u should change the block and buy a new original piston .may be 2nd os .50mm . i hjave a extra rx100 bore which is 25mm .. if u want it give me your address and i will send it to u cuz i dnt need it .... hops so i cud help ..

Hey ivanboy_9,

thanks for your concern a month back i changed it to a new one (genuine)

thanks a lot.

Need help!

Hey there Ivanboy_9. I badly need to replace the bore in my rx100. I recently bought the bike from another state only to realise that the previous owner had replaced the bore with a duplicate one. The poor bike has no pick up and the engine cries for more power. Please help as its hard to find a oem bore these days and the new ones I hear aren't up tp standard. Thanks buddy...

i might be able to help if you show me the pic of the altered cylinder block from the side.

there is no point in machining the cylinder block from the top. what happens is there will be too much exhaust and transfer duration and not enough intake duration. the crank case charge volume and pressure will be too low and half of the fresh charge which is drawn in will simply go out through the exhaust port, which equates into poor volumetric efficiency.

if you want it to work, you need to machine the block from the bottom. not the top.

i guess you can machine it from the top(i've never done it). but you'll have to radically alter the exhaust and transfer ports. the piston skirt too has to be modified.