Tracks and Chain Tensioning

1. Tracks and Chain Tensioning Distributor Conference 2006 Workshop

2. Tracks and Chain Tensioning Background Installation of rubber tracks Research Goals Variables Results Conclusions/Recommendations

3. Background info:Chain Tensioners • 1996 R&D work on new tensioner • 1997 Introduction of tensioner on Bigfoot (new model Argo) • 1998 Migrated up and down to all Argo models, Vanguard through Conquest • 2003 Avenger intro. to Distributors • 2004 Avenger manufacturing startup end of January

4. Background info:Chain tensioner features/benefits: ·Semi-automatically adjust to new “fixed” position ·Extends chain life 2 to 3 times by taking up more “stretch” before touching the frame and also reduces shock loading ·Eliminates chain tensioner “slap” on floor pan during turns ·Eliminates vehicle lurching during turning caused by stretched out chains

6. Background info:Tensioners currently used on: • Avenger EFI, Avenger, Response, Frontier, Vanguard 2, Vanguard • All models since 1998 (’97 for Bigfoot)

7. Background info:Tracks: • Since . . . early ’80s as plastic segmented track • Rubber tracks were desired for increased wear/life/traction • 2000 – 2002 Centaur All-Season Tracks and Winter Tracks developed and introduced

8. Background info:Tracks: • 2004, Jan. – June Development of rubber tracks for Avenger • 2004, September Introduction of track kit • 2005, Jan. – Mar. Testing/evaluation of tire sizing and track tension • 2005, April 4 First Hinge Kits c/w Extensions sold

9. Background info:Some problems (symptoms): • Worn tensioner blocks and damaged components • Premature bearing and flange failures • Broken axle hubs

10. Background info:Definitions: • Chain wear • Chain stretch • Chain windup • Forward loading • Reverse loading • Over-tensioning

11. Installation of Rubber Tracks (Things your mother never told you.)

12. Research • 700 lbs of iron • 223 lbs of driver • 200 meters of dry pavement • 110 tests • 16 tires • 2 rubber tracks • 1 unfortunate Avenger

13. Goals • Eliminate reverse loading • Reduce chain tension • Avoid track walk-off • Maintain traction

14. Variables • Tire size • Tire pressure • Track length • Tire direction

15. Chain tension tester was constructed using a load cell • Tester was mounted onto the frame of an Avenger

16. Free-wheel hubs • Iron weights • Track Extensions

17. Test route: Drive 100 meters, turn around, and drive 100 meters back.

18. Effect of small variations in tire size with a tight track: • Blue: Front tire is virtually the same size as the rear tire • Red: Front tire is smaller than rear tire • Green: Rear tire is smaller than front tire Tight tracks = Chain wind-up

19. Effect of small variations in tire size with a loose track: • These are the same tests as the previous slide • The track has been lengthened by 2” Loose tracks = Lower chain loads

20. Effect of adding/removing cargo (tight track): • Blue: with 700 lbs • Red: weight removed Tight tracks = High drive train wear

21. Effect of adding/removing cargo (loose track): • Blue: with 700 lbs • Red: weight removed Loose tracks = Happy drive train

22. Measured tire size vs. actual tire size Red: Measured size Blue: Actual size on Argo (unloaded) Yellow: Actual size on Argo (loaded) Measured size is not the same as effective size!

23. Effect of tire tread direction on rear chain load: • Red: Tires mounted in standard direction • Blue: Tires mounted in reverse direction Reversed middle tires = lower chain loads

24. Recommendations: For rubber track installation on the Argo Avenger: • Inflate all tires to 5 psi. • Measure and record all tire circumferences. • Install tires as shown in chart. • Deflate end tires and install track. • Inflate tires as shown in chart.

25. Recommendations:

26. Recommendations • Track Length: 235” total • Track Sag: 2-3” under middle wheels

27. Conclusion: • Reduced chain loads • Longer lasting chains, bearings and sprockets • No chain over-tensioning • No reverse loading • Greatly reduced wear on slider blocks • Better drive efficiency Questions?