I.D. 2 stroke motor help

[MotoMagz]

Hey guys I haven’t had a 2 stroke in 15 years and only had the one Before the switch to 4 stroke. I picked a a couple used kits today and need help with identification. I took a few pics of the outside...is that enough? Thanks

 

[Greg58]

48cc and early 66cc engines had 6mm head studs, later 66cc-69cc engines have 8mm studs. The 66cc is 38mm stroke, the 69cc is 40mm stroke.

 

[Greg58]

To check the stroke take out the sparkplug and find top dead center, take a drinking straw and touch the piston and mark the straw with a sharpie, rotate the engine to bottom dead center and mark the straw. Now measure the distance between the marks, it not totally accurate but will be close.

 

[Greg58]

If you download the gasket templates below the head gaskets for each are there.

Gasket Templates

I had a problem a few weeks ago when the base gasket failed on one of my 48cc engines and I didn’t have one, I managed to make one but a template would have made it a lot easier. The templates below are for 48cc and 66/69cc engines. If anyone wants to add please do so.

motorbicycling.com

 

[MotoMagz]

Cool... Thanks a bunch! So many parts out there, I want to be sure what I have. As soon as I find time I’ll rip into it. Greg58 thanks again.

 

[Greg58]

You don't need to take it apart, just print out the gaskets and compare the bolt pattern.

 

[Greg58]

There are two piston types,you can measure yours if you pull the cylinder.

 

[MotoMagz]

Thanks again For taking the time Greg58 !! All great info I Needed. Going to be a little while before I get to the motor but this is all saved.