Hi.

Hope you all doing great!

What cylinder head and barrel would fit on the engine of my bike? Im really curious of up the cylinder to 175cc just for that little extra power and as a fun experiment.

I might have a chance on a -74-75 cylinder, 443-11311-01-00? Would this fit? It comes without head tho’ but i believe heads are more common on ’bay.

Or do i need a newer one since mine is -77?
Give me your thoughts.


Best regards

Earlier 175 should fit the 1G0. In terms of USA bikes would be 1972 through 1976.

You should have four long studs that go through the cylinder and into the head.

(Later models had four short studs holding the cylinder to case and then more short studs holding the head to the cylinder. That type will not fit.)

Note that before 1976 most Yamaha's had the autolube line directed into the base of the cylinder. Your 77 likely injects into the carb throat. The 74-75 cylinder will work fine but you'll need to plug the oil injection port in the base of the cylinder with a small bolt.

Get a 74-75 175 head to match, suitable 175 piston and rings for the cylinder, 175 piston pin, 175 piston pin bearing, piston pin clips, and gaskets and you'll be good to go.

Thank you once again MarkT. You are very nice to help me with this good info.

Oh i wonderd what that hose on the side of cylinder was. Now I know.

Yes i’ll Try to find a head to it aswell.

The cylinder has 3 broken finns on one corner. Is this critical For cooling?

Best regards.

On broken fins, depends on how much is missing. Big pieces missing could be a problem.

Got it. Im not buying that one. Felt wrong with the fins. Almost a complete corner missing on all levels.

Best regards

Makes you wonder what the PO was doing to screw it up like that, and what the inside might look like, given the outside looks like that.

Yes so do I. Bet it been dropped or something. The inside looked good tho’

Best regards