Hi everyone, I just joined a few days ago.

Anyways my bike is an old 1978 IT 250 dirt bike. I got it from a friend of mine as it didn't run anymore and I started repair work on it but he lost interest and just let me have it.

Anyways, what I am looking for is information on the cylinder jug. The piston had tons of play in it and so I removed the head, piston, piston pin, and cylinder. Anyways I removed the cylinder and piston so that my friend could take it somewhere and have it rebored and a new oversize piston could be ordered so that I could put it all back together and get the bike running good. Long story short, the cylinder was at his parents house who moved to another state, and it's gone missing.

Worn out:

So really what I'm asking is what other cylinders are interchangeable with an IT? I worked on a sweet DT250B two summers ago, and I just finished getting my Honda CL350K2 back on the road, so I'm familiar with bikes.

The DT250

My CL350

Just looking for interchangeability between the Yamaha 250 2 strokes. IF there is any...

*bump*

Also here's the number from the right side of the frame where the triple tree mounts:

2K9-001736

I'm guessing the 9 in the first series means it's a 1979?