Very Cheap and Easy MOD for more Horsepower and Torque (at ALL RPM) for ANY SAW!

[Bandmill Bandit]

Yes EHP that little 340 Rotax was one tough competitor 11500 to 12500 was their sweet spot but with a Kawi and a Spirit you needed another 1200 to 1500 RPM to beat them.

There were few guys running Yammies in Sno Jets and Rupps that  would just scream in comparison but like us they had trouble holding the clutches together. Don't know what RPM they ran at for racing but it sounded like they topped us by at least a 1000 RPM.    

We didnt base our actual RPM numbers on an electronic tach on the sled. That came from the Dyno tests with a cable tach done on the bench before the motor was installed and we even assumed  a +/- 500 rpm error margin on that.  

That 9000 ish RPM limitation was one of the primary drivers for the development of what became the Comet Clutch. By 75 Polaris along with rest of the factory teams had some pretty impressive clutches running on their SnoPro Factory sleds and were running a lot higher than 9000 RPM. You couldn't get near the shop trailers in the pit for any of the factory teams. Polaris seemed to have the edge on clutchs in the semi Pro and Pro classes that season.  

I think the 74/75 season was the peak of those racing years. By 1980 factory teams were a shadow of their original glory days.         

[sawguy21]

I started my small engine career in Arctic Cat shops in the mid 70's, you guys are bringing a smile to my face. We weren't involved in serious racing but had a few tricks up our sleeves too. ;) And yes, clutches were a limiting factor.

[gspren]

  I'm afraid we scared off the OP , please come back and tell us what happened.

[Pine Ridge]

 smiley_horserider

[Al_Smith]

 I'm afraid we scared off the OP , please come back and tell us what happened.

Some times things aren't really a good idea once every thing is well thought out .It happens,been there .  ;)

[Northeaster]

As someone just mentioned a broken fin causing issues, i broke one on my early model 064 (which I just rebuilt and haven't run too much since rebuilding) and I thought I had read somewhere that the balancing was not precise enough on a saw flywheel to matter...for just a broken fin.
can anyone comment please? 

[Al_Smith]

My only comment is don't try locking the flywheel using a bar in a fin .If I get a broken fin on the used  saws I buy I replace the flywheel before I use it very much . I've got one right now as I type on a Partner P100 somebody evidently didn't know how to remove properly .I've also got a complete lower unit including a flywheel,clutch and rotating assembly to restore it .---some times a total restoration takes a long time especially on a less than popular saw because of a shortage of usable parts .If you do it right you'll never have to do it again ----but if you don't ----- :'(