96 honda elite scooter 49cc 2 stroke wont start,any help?

i had a new cylinder bore of 50 over, i installed new rings new head gasket, bottom cylinder seal, torqued everything according to specs, i cleaned carb. put new gas in. new oil in the injection system, i checked and i have good spark , but it still wont fire, any help would be greatly appreciated.

It's possible that when you put the cylinder on, you may have snagged a ring on one of the ports. 2 stroke pistons have a pin in the ring grooves to prevent the rings from rotating. If the opening of the ring were to get in the intake, exhaust or transfer port, the ring would break.
Also the people that bored the cyl may not have chamfered the ports. Chamfered means to smooth the edges of the ports so the rings will slide up a ramp until it gets back to the cyl wall.
Check the compression and maybe take the cyl off to double check.

Any gas in it...? Fuel line clogged...?

have you tried kicking it

If you bored out a 49cc to 50 over, there's precious little metal left on that cylinder wall. I'd do a compression test on it to see if you haven't holed a piston or something...

If you are getting good spark and it still won't start its in the carb. You cleaned the carb I know but you need a carb kit to replace the old gaskets and rings in the carb. Carb kits are cheap so try that.

sounds like a 'timing' problem.....sparking at the wrong moment during the cycle.

if it 2 stroke an you have fuel an you have good spark (at the plug) then it is timing


tic a tic a tic a timing, as the song goes

why did you bore it out?, could not have been worn that bad?

well did you manage to put the reed valve back in ??? thats what controls the fuel coming into the engine. compression is another place to look.

Did it run before the rebore? Did you line the rings up with the locating dowels on the piston, come to think of it did you fit the new piston?
If you fitted the barrel and piston assembly correctly and didn't manage to break the rings, then you could have an air leak at the carb, mis assembled the carb, left bits out like the float valve or disturbed the float height setting. Did you fit the carb slide right way around, with the semi circular cut out towards the air filter - very common mistake.

Without seeing the bike or knowing more its very hard to diagnose these things, but I suggested the most likely suspects.
best of luck.