05 Yz 125 Top End Swap?

[fritzfab]

I have a 05 yz125 with the athena 144 top end... no head gasket problems yet(fingers crossed). But what I'm wondering is if it is possible to swap a complete top end from an 04- earlier yz to an 05, if I decide to go back to the 125cc?

 

[fritzfab]

Any thoughts, anyone?

 

[skos]

I have a 05 yz125 with the athena 144 top end... no head gasket problems yet(fingers crossed). But what I'm wondering is if it is possible to swap a complete top end from an 04- earlier yz to an 05, if I decide to go back to the 125cc?

The Bore x Stroke are the same but the Compression Ratio on the 2004 is 8.7 – 10.8:1 and on the 2005 is 8.6:1 – 10.7:1

 

[Pete Payne]

The 05 was an all new engine and will not interchange with the older stuff, But you can use the newer stuff -06 07 08 etc.