Engine Trouble one jug gasket instead of two? timing issues?

[jatgm1]

i have a 66cc grubee skyhawk engine, the jug crapped out, i swapped it with a new one, i put one gasket because i only had one, but originally it had two.
at open throttle it seems like it bogs out, however i put a smaller jet, and then it died out when i revved it, or just used it at all after turning off the choke. i replaced the entire fuel hose, got a high flow petcock valve, and new fuel filter. (after having issues not before)
ive tried jets from #80 to #55 in increments of 5. id rather not have to take the jug off, does it seem possible that a single gasket would make it bog like that? it almost sounds like its 4 stroking, if i apply the throttle fully(or more that 1/3 of the way on flat land) it starts firing weird. (with a size 60 jet)(dellorto sha carb) would that single gasket really cause this kind of problem? also, gas and oil keep winding up in the intake.
I assume the ports are not lined up right or the timing is off or something. i have two gaskets now, i just dont want to go through the effort if im totally off base. or if i can just get a jaguar cdi and tune it to the way the piston and cylinder is now. (dont really care if theirs oil in the fuel filter to be honest, just want to go at a decent speed.)

 

[WINDY CITY BOB]

You're rite I'm sorry I created. Different post /thread my apoilogize

 

[butre]

messing with the number of gaskets messes with compression and port timing, which messes with jetting. it should be making more power on the low end with only one gasket, as that's how many the engine is supposed to come with. I've run no base gaskets all the way to 3 base gaskets on different motors that needed to make their power at different rpms, it's a cheap and easy way to experiment with port timings. on piston port engines I generally don't use a base gasket at all, just throw a little bit of paint on the mating halves, let it tack up a bit, and put them together. on reed valved engines I'll usually run 2 or maybe even 3

 

[jatgm1]

can you explain what port timing is and how it relates to ignition timing?

 

[crassius]

ports are opened/closed as the piston moves past them - with extra gasket, ports sit higher while piston is in same old place - wouldn't hurt to try to get them back where they were - but problem may be a slight diff in cylinder size since standards are loose in these factories

 

[jatgm1]

okay, added another gasket, (took forever to scrape the rest of the original gasket off) and now it does indeed perform better. i had no idea such a small thing could screw an engine up so much.

 

[butre]

can you explain what port timing is and how it relates to ignition timing?

port timing doesn't relate to ignition timing. messing with port timing is the 2 stroke equivalent of messing with the cams

 

[jatgm1]

thank you, actually after i looked up a youtube video i figured it out. these little things are mind blowing to me. out of curiousity, is the grubee skyhawk engine design based on anything made by a reputable company? like an old honda or yamaha engine that they changed a bit?

 

[butre]

it's a mostly original design, but it draws heavily from an old Latvian moped engine. you could call it a clone, but I'm hesitant on account of the fact that there's zero parts commonality.

 

[jatgm1]

do you happen to know what the name of the company that made the engine and the engine model is? or where info on it could be found?