Squish is about 40% of your bore. I’d be more worried about msv. I purchased bimotion software and would input all the info. You will need to know the dome rise of your piston. Certain squish velocity numbers are different for different set ups. Drag racing, mx. Do a lot of reading.....


http://www.trx250r.net/forum/engine-transmission/3089-squish-band-width.html#/topics/3089