RacerDave
Expert
Highmark and Tracks USA both make 136 extension that also extend the hyfax. When doing this are there still differences where the torque arms mount to the rails, and to the tunnel? Or is the factory 136 rails just longer like adding extensions? RR

Yamaha Sled Talk Blog
VIP Member
- Joined
- Mar 20, 2007
- Messages
- 104
- Reaction score
- 0
- Points
- 396
- Location
- Hopefully Canada
- Website
- snowmobiles.yamahablogs.ca
The skid frame in the Attak is different from the Apex, engineering determined that for the mono-shock to work correctly the geometry had to compensate for the longer rails, they did not simply extend the 121 rails. They are also reluctant to go any longer than 136 with the mono design... cr