Grizzly 700 Shim Mod Install and Drive Belt Change for More Low End Power and Faster Hole Shots!

Performing the shim mod on a Grizzly 700 Ultramatic transmission is one of the easiest ways to gain a considerable amount of more bottom end power.  The modification is also affordable, because the shim will only cost you a couple dollars and some install time.  In this article I'll explain the advantages, disadvantages and how to do it.

The advantages to the shim modification include: inexpensive, requires only basic tools and mechanic skills to install and provides the Grizzly with a lower gear ratio.  The modification works by allowing the drive belt to seat further down into the primary clutch sheaves.  This modification can be done at any time and is reversible.  The best time to complete the shim modification would be when replacing the drive belt since it requires basically the same procedure.

Disadvantages to the shim mod include: lower overall top end speed and shorter drive belt life.  Essentially all the low end grunt this modification produces equally reduces the Grizzly's over-all top speed.  You'll likely get less mileage out of your belt because the shim spreads the primary sheaves and has less distance before it bottoms out on the collar between the sheaves.

This video will show you how to install the shim modification during a drive belt change.