No compresion on rear rotor
 

Have a 13b with 2 weber carbs the engine has barley no power i pulld all spark plugs n rear rotor has harley no compresion im tryn to figure out wat can b the problem n if its fixable

Perform a compression test.

Probable blown rotor/seals
 

Welcome to the bane of rotor owners. If there's little to no compression then the only thing it means is the tip seals are gone. And of course most likely the rotor and housing with it. It's possble the iron castings are salvagible but that's a long shot as well. Most often they take a hit too.

I'm the proud owner of two of these. :-(

The only answer is a rebuilt engine or a rebuild job on what you have left plus the previously mentioned main parts.

Russ