So i just picked up this 1979 Yamaha 650 special today from my uncles it wont run im getting compretion (around 150psi per cyl)&spark when i spray starter fluid into the cyls it dosnt make a noise like its trying to start im wondering if anyone has any idea on what would fix this

 

Idk much about yamaha twins but if it has a points ignition system I would say thats your problem. Clean the carbs real good also. If you have spark and you have fuel then it should run. I would suspect it to be a timing issue. If it is a points system clean them up with some fine sandpaper. Is that an XS650 by chance? The early 650's are becoming highly sought after as they favor the classic brit bikes of the 60's and 70's. I have been looking for a basket case bsa,triumph or a yamaha to build a retro cafe racer or bobber out of. They make all kinds of cool stuff for the yami 650's (ridgid frames,bolt on hard tail kits,fork retro fits) and if you mill the yamaha logo of the engine side cover most people think they are triumphs.

 

Ya I belive it is an xs650