Did this last yr on mine - only went to 162 x 2-1/4
As above - you need to grind some stuff down, turn some others around. I dodn't notch my track for anything tho. ???
Instead of grinding much on the drop brackets in the back - I think I just used a cpl worshers on each side to spread the tunnel out around it a little better.
I went with the 3" pitch 7 (?) tooth drivers. These are a little smaller, but not a lot. Should work out well with your current gearing if you go to 3".
If you doo not have extrovert drivers - I would highly recomend them! The more traction you get, the more likely it is to ratchet the drivers.
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