Honda Spree and Elite 50 Forums

Hello Everyone I'm about to install the 50mm NCY cylinder just had a question the piston covers about 1.4-1.5 mm of transfer ports and the exhaust



Is this normal I check the port timing Exaust opens at 92 degrees ATDC and Transfers at 120 degrees ATDC so its 28 of blow down and with the head and gasket installed i get about 1.8mm of squish parallel to the piston pin is this excessive?

Are you sure that isnt a stroker bore?

Meatball wrote: ↑Mon Oct 09, 2023 4:17 pm Are you sure that isnt a stroker bore?

I acquired the 50mm Kit and the NCY Dio / Elite pipe for it at SSS. I checked the deck heights on stock cylinder 62.5mm and the NCY 50mm is 68.1mm, shouldn't they be the same height?

Well good folks I installed a base gasket of 0.39mm and just skipped the head-gasket and just copper spray the head now I have about a 1mm squish. With the compression test COLD with little oil down the spark plug hole I got around 155psi at first then tested about 5 more times with a 14mm socket on a drill its consistently getting around 135-137psi with the intake and reed valve off and I'm guess it will go up alittle more after the rings seat and warmed up. Exhaust is now 93 degrees ATDC and transfers 121 degree ATDC. I'm gonna assume that the peak power will be around 6500-6800 rpm? Just not all that thrilled that piston covers part of transfers and exhaust port.