Thanks for that mark.
I've ported the intake to about 22mm and the exhaust, I'm not sure on the measurements of the exhaust port but I've basically rounded it as much as possible right through to the bore. I also angled out the channels running from the crankcase that deliver fuel an air to the combustion chamber, probably 4mm on either side of each port. I think I should go a lot further with those but I'm not to sure ATM (will upload photos Tommorow).
Other than that I'm waiting till next pay day and I will order a cylinder hone, piston rings, o rings and a carby. I'm not sure if I will need to buy a new piston but according to the micrometer the bore is currently 4-6 thou bigger than the piston. after much consideration I think a fair bit might need to be taken off the bore as there are some marks from dirt, and I don't see the point of chasing more power if I'm losing power from a poor cylinder bore.
Another thing I'm still somewhat unsure about is the carby. The standard carb is roughly 16mm into the block. And a lot of people put a 26mm on, however the inlet port can't really go bigger than 22mm and a bigger carby would only result in a loss of low to midrange power. I found a calculator online that estimates a 20mm carby will be the best fit to peak power at 6000 to 8000 rpm.
I honestly don't think the engine will hold up to more the 8 grand,and I've found a 19mm high performance replacement carb for the stand 19mm ones found on 50-80cc pocket bike. I know these carbs are designed for a much smaller engine but a lot of those 49cc mini bike rev well past 12000rpm.
Thoughts on my theory anyone? The carby I found is $28 including postage and pod filter I would copy a link but I'm on an iPad and well......
An exhaust will be the last thing I buy, I'm thinking of just getting any 2 stroke exhaust that has baffles and the same diameter as the exhaust port. Would this be the best way to go as making one up is a bit beyond my interests ATM?
I have considered a trumpet but my commodore with a full blown speedway engine pisses the neighbourhood off enough as it is
(before I need a flame suit I would like to state no I don't hoon around local streets)
I'm open to any thoughts and constructive criticism on anything I've mentioned, after all that's why I'm here.
