Some 2009 Ski-Doos came with a new belt deflection adjuster on the secondary clutch (it was a running change on the assembly line), but our MX Z Renegade 800 demo sled had the original-style, plastic adjuster that is known to loosen or wear out. Not willing to risk this part failing, we installed Fett Brothers Performance’s aluminum QRS Secondary Adjuster Bolt.
The FBP adjuster functions similarly to the stock Ski-Doo part, but it’s simpler to use because the aftermarket part holds the spanner wrench more securely than does the adjuster that was stock on our machine.
To adjust belt tension on Fett’s part, tuners first loosen the lock-bolt with an Allen wrench. With the bolt loose, we turned the cam in or out with the Ski-Doo suspension spanner wrench to set the sheave width as necessary and then tightened the bolt to hold the setting. We adjusted the belt deflection several times and used it to change one belt over 600 miles of use last season.
Installation took less than five minutes. We spun out the stock adjuster and screwed in the FBP part, set the deflection and tightened the lock bolt according to Fett’s instructions. Our sample FBP QRS adjuster bolt kit backed out within the first 10 miles of use last season, but we re-torqued it and had no further trouble. FBP co-owner Dale Fett said last winter that ours was the first one he’d heard about loosening. Maybe we didn’t tighten the screw well enough.
Adjuster kits sold last year didn’t include the quarter-inch Allen wrench so we had to supply our own tool, but Fett Brothers will include it this season. The QRS Secondary Adjuster retails for $79.99. If I owned a REV-XP with the plastic adjuster, I’d put this FBP part on my sled for peace of mind and because it’s easier to use.
— Andy Swanson