Hello, my name is Michael and i just received a 1981 Yamaha 550 Seca from my grandpa.I got excitied and got it back home by myself with the chain and rear tire locked up. Once inside the garage I started to clean it up and noticed there were no spark plugs. After letting the motor sit with several different rust breaking oils for months. The motor never did come unceased. I have since tore the engine apart and thr cylinder walls are heavlly pitted. After takking with some people it was brought up to have it bored to the next size, 650, but after posting a subject in this forum it would cost less just to get a new cylinder head.

The next question that has been brought up to me is the it looks like the cylinders are sleeved. I was wondering uf anybody knows if they are and this woukd be much easier. Any advice would greatly be appreciated.

Michael

HI mike"  its not  a model am familiar with 

most of the yam cyl have cylinder liners and if you do get them replaced ( I did on the fz600), you need them skimming also to bring the deck inline