Exhauast port

[gra1972]

ok guy ive just blown the exhaust gasket on the 66cc, last night when i was looking on here i seen a pic of the exhaust port and when the piston was top dead center you could look through the port and see the bottom of the piston , well just took the exhaust of to check mine and when the piston is top dead center the whole port is covered by the piston , on the bottom stoke you can see the top of the piston is this right ? the bike runs fine but could go alot better

 

[gra1972]

could the jug be back to front ?

 

[Venice Motor Bikes]

You shouldn't be able to see under the piston through the exaust port.
Your's is fine!

 

[gra1972]

cheers mate thank you

 

[Gary Harris]

ok guy ive just blown the exhaust gasket on the 66cc, last night when i was looking on here i seen a pic of the exhaust port and when the piston was top dead center you could look through the port and see the bottom of the piston , well just took the exhaust of to check mine and when the piston is top dead center the whole port is covered by the piston , on the bottom stoke you can see the top of the piston is this right ? the bike runs fine but could go alot better

I'm confused.

 

[Gary Harris]

After thinking about it for a minute, I assume these engines are piston/port timed since their are no reed valves etc.

Two-stroke engine - Wikipedia, the free encyclopedia

 

[Gary Harris]

You shouldn't be able to see under the piston through the exaust port.
Your's is fine!

Or lose the compression in the crankcase during the compression cycle!

 

[dmb]

valve overlap on a twostroke? [works on fourstrokes] on a second thought maybe its a chineeze egr? the new epa motors..

 

[The Busted Nut]

 

[dmb]

busted nut.. perfect xzample i really like the atomizzer

 

[The Busted Nut]

Thank you. Here is a four stroke, since you mentioned it above: