136 to 141 how far to move the holes back for the skid

[cooksend]

I would think that anytime you increase the distance between rail tips and the drivers that is should be done!

 

[reiley99]

You need to move them back 2.5" and both Yamaha and Arctic Cat ran 141" x 2.52 pitch tracks for years on their mountain sleds.

you think I will need to go back alittle farther if I'm going from 9 tooth to 8tooth drivers