ORIGINAL: Bax

The SuperTigre S-90, S-90K, and G-90 are similar engines. The difference between the S-90 and S-90K are styling. The "K" has the squared-off cylinder and head. The G-90 is basically similar, but has a one-piece crankcase instead of having a removable front housing.

All three engines have roughly the same power output and handling. The carburetor is virtually identical in all three. The S-90K and G-90 use the same muffler mounting. They have the "bolt-through" muffler mounting, while the S-90 has the "bolt-on" muffler mounting.