| 1970 |
Adjustable Keel For Snowmobile Skis - # 3,632,126 Blade like |
| 1971 |
Anti-Skid Device - # 3,718,341 Shorter but still fins |
| 1972 |
Roetin adv. – Ski Trac Blade like |
| 1973 |
or earlier Mercury ski with a Polaris rockered track cleat bolted on, providing fins in place of a wear rod, found in a salvage yard. |
| 1973 |
Snowmobile Ski System with fins - # 3,844,367 |
| |
Used Blade like rod ¾” tall by ½” wide with a rounded channel on the bottom found on a Rupp in a salvage yard. Note the even wear. As is, the rod now weighs 3 lbs. |
| 1976 |
Hex rod drawing Blade like ¾” tall, increases the effort to turn the handlebars. |
| 1991 |
Polaris EZ-Steer patent - # 5,344,168 – Got rid of darting but still pushed in the corners because the pressure was still on the flat front. |
| 1997 |
Self-sharpening carbide – Eversharp flyer - The carbide broke off as fast as the steel wore leaving only a 1/16th inch exposure. |
| 2001 |
SLP- Keel Blade – Adds a short fin to the front of the wear rod. Note the heavy wear on the front of the host bar and used Keel Blade. The bolt on the Keel Blade goes in the front bolt hole matching the regular 3 bolt host bar. |
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