Chainsaw Repair

My 3120 only has a baby small 24 inch bar. You would think that it should easily pull a 9T or 10T

Good advice Kevin you have been there and done it.

Depends what species of wood you're cutting down under Fabian. 9T-10T in 3/8[.375"] is possible in softwoods with a unmodified 3120-24", but not in that tooth count in the larger .404
If you don't plan on getting into speed cutting competitions,if only work then keep the .404 setup [rim,sprocket bar nose & chain] The most durable and longer sharpening chain size out there for todays hand held saws.