I wanted to fit a 25t and found the motor fouled the motor cover so couldn't fit any bigger than the 22t. But.....if you undo the motor cover then mesh the gears, then bolt down the motor cover it fits. I have been playing with everything from 22-25t on mine. Doesn't seem to make much difference though....lol.
For the record I ran a 23t/87 and a 19t brushed at bridgeford, seemed to go fine, until Pat performed the PIT manoeuvre on me
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Mazda 787B