Need help please with finding out year of this Engine?

[ECgasser125]

Any ideas I know its a EC125 but thinking its not the original motor cause title says 05 EC125 but the piston looks like piston for an 03 letter B is also on the head and the piston is 53.96...Did they put wrong piston in it

 

[Rick]

How does the cylinder look? Looks pretty dry...someone forget to a oil?


http://www.wiseco.com/ProductSearch.aspx Try this....

 

[pscook]

Specifications call for a 54mm piston. I wouldn't question the "03" marking on the head, I doubt that would signify the year. Maybe the casting lot, but probably not the build date.

 

[ECgasser125]

Only reason I question the year is because and 05 should have a port on the piston like a square opening and this piston is just solid

 

[ECgasser125]

They started that piston in 2004

 

[ECgasser125]

How does the cylinder look? Looks pretty dry...someone forget to a oil?


http://www.wiseco.com/ProductSearch.aspx Try this....

Cylinder looks fine didnt get messed up..someone just ran it till it would run anymore

 

[Rick]

If the 125 motor is like the 200,250&300 there should be a tag or stamped series of numbers down by the shifter shaft. The number will break down the year and type.

 

[GGRider01]

Cylinder looks fine didnt get messed up..someone just ran it till it would run anymore

Wow.. that's hard to believe. I would get it inspected by a good machinist, at the very least, to make sure it's not out of round and of proper diameter.

 

[ECgasser125]

Wow.. that's hard to believe. I would get it inspected by a good machinist, at the very least, to make sure it's not out of round and of proper diameter.

Theres a bit of the piston melted to the cylinder but im getting it honed and it will be fine. Just took it to machinist today he even said cylinder is fine just gonna clean it up

 

[Jim Cook]

The early 125cc GG engines would use the Yamaha pistons.
Your's looks to be the stock flat top piston. 53.96 is the "B" piston in a stock bore size.

http://www.athenaparts.com/eng/sections/view/78/forged-pistons/page:4

You might think of going to the"C" piston. Same bore, just 1/100th millimeter larger in diameter.