1972 Kawasaki G4TR Trail Boss

I never thought I would make it past 30 years old. The all wild all the time lifestyle seemed fun,I lived through it and here I am. 61 years old still dirt riding.

So a friend dropped a bike off for me to fix. A 1973 Kawasaki 250 F11. I thought you guys might be of some help. I haven’t worked on a 2 stroke for a while and I’m unfamiliar with the rotary valve setup. Seems this bike has zero compression. Before I pull the cylinder to see if it’s a piston issue is there a chance this might be a rotary valve stuck open?

The rotary valve doesn't impact compression above the piston.

Thanks for the reply. I’m not pulling it apart. It’s a piston then and this guy doesn’t want to put any money into it.

Wait. I didn't think it thru. If the valve were stuck closed, the piston would starve to refill and create full compression.
You can look thru the carb to see if valve spins the with crankshaft.