My caged lower bushings were worn out, so I replaced them and built some hub locks while I was at it. I had 6 plates made, so I can sell 5 of them for $80 each shipped via paypal. These kits will include a 14mm hex, a laser cut steel plate, and attaching hardware (studs, nuts, & washers), all made in the USA, and will need some fitting and finishing to your caged lower pulley drive described below.
This will keep your lower cage from getting jammed on too tight with smaller blowers, or worse yet the tribar getting plowed through from the driveshaft continuing to tighten beyond the factory stops, which are lightly made. The hex will need to be welded in to your plate at the proper depth, and the 3 holes in the plate will need to be drilled from 0.330" to your choice of size to clear the 3/8" studs, I drilled my holes to 0.390". There have been several ways to attach the lock plate. The way I attached mine is the 3 holes in the tribar were drilled and tapped for 3/8-24. The existing holes in the tribar are almost already the right size for this, they measure about 0.330" diameter at the front edge. I installed setscrews as studs with red loctite to a depth flush with the rear face of the tribar. There was only about 0.050" of clearance behind the tribar between the outer front edge of the support bearing and the back of the tribar when installed, so that is one reason I went the way I did. I also left a little clearance behind the hex in the drive plate so the plate will bottom out on the front of the tribar before the hex bottoms out in the factory 14mm hex bore. A 9/16" hex (0.5625") would not fit in the 14mm hex (0.5512") drive bore, as mine has not seen any impact wrenches. I also bolted the lock plate down to the tribar for welding, and welded 1 flat at a time in a criss-cross pattern. I left a 14mm hex stub sticking out on the front to be able to turn the engine over by had if need-be. Bondhus rates the 14mm hex key to 673 ft-lbs of torque before it permanently deforms, but welding will take that down a bit.
An example of a finished piece shown below
This will keep your lower cage from getting jammed on too tight with smaller blowers, or worse yet the tribar getting plowed through from the driveshaft continuing to tighten beyond the factory stops, which are lightly made. The hex will need to be welded in to your plate at the proper depth, and the 3 holes in the plate will need to be drilled from 0.330" to your choice of size to clear the 3/8" studs, I drilled my holes to 0.390". There have been several ways to attach the lock plate. The way I attached mine is the 3 holes in the tribar were drilled and tapped for 3/8-24. The existing holes in the tribar are almost already the right size for this, they measure about 0.330" diameter at the front edge. I installed setscrews as studs with red loctite to a depth flush with the rear face of the tribar. There was only about 0.050" of clearance behind the tribar between the outer front edge of the support bearing and the back of the tribar when installed, so that is one reason I went the way I did. I also left a little clearance behind the hex in the drive plate so the plate will bottom out on the front of the tribar before the hex bottoms out in the factory 14mm hex bore. A 9/16" hex (0.5625") would not fit in the 14mm hex (0.5512") drive bore, as mine has not seen any impact wrenches. I also bolted the lock plate down to the tribar for welding, and welded 1 flat at a time in a criss-cross pattern. I left a 14mm hex stub sticking out on the front to be able to turn the engine over by had if need-be. Bondhus rates the 14mm hex key to 673 ft-lbs of torque before it permanently deforms, but welding will take that down a bit.
An example of a finished piece shown below