Chopping rails on IQ's for extros?

[mountainhorse]

BTW.... I agree with Ron 100%

If your track is run loose you will loose performance and you have a good chance to stab a rail...

Rider weight changes track tension so in my definition of rolling resistance-it is in the snow with the rider on the sled.

And he makes the perfect point that a track on a stand is MUCH different than a track in use.

 

[Ron]

Boy we got the juices flowing now.
Here's what I know....Carls has put out a few big bores, long track sleds with 840, 860, 910 & 975 that are not running Avids & have not had track problems. I have a good friend that ran a PSI 1085, a 910 Polaris & last year an 840 all Carl's Cycle builds but the PSI; none had Avids-none had track problems ratcheting or broken tracks internally. Lost a cleat or two. Personally know of several turbo Poo's same story.

Like Matty said moving the mounting points back changes sled geometry & handling.

Carl's (Jack) told me that his issue with cutting the rails is-the distance between the driver & the rail pickup point creates a performance loss as the track trys to follow the driver creating a small loop in the track. That's the reason that Polaris went to a center extro rather than combo ones. Yes I'm going to assume that Jack has tested some of this in the past, he tests everything. (Including R&D with Polaris Industries & or SLP a couple of times a year.)
I run SLP Powder Pro skiis in powder & the stock skiis in spring snow. Haven't decided yet on SLP twins or SLP Single with porting, for my engine-both about the same on the dyno.
Just trying to present some info here for the peeps with stock sleds-even if not everyone agrees. Mod guys want what they want, change tracks, larger drivers, Tunnels, etc. etc. Once you start adding big HP to a sled a small loss in performance from Avids is insignificant anyway.

 

[MNIQR]

Here is a pic of the 2008/9 RMK Dragon Drive shaft... the spacing between the drivers is pretty close.

You know a guy could trim the inside "nubs" off the 2 outer drivers to help increase the effective gap between the outers and the middle driver. Wow that was a long run on sentence!

 

[gerrman]

Quote "Like Matty said moving the mounting points back changes sled geometry & handling."


I am only going to set the suspension back 1". The rest of the difference in the new track length will be made up in the rear wheels. Ron, do you think a 1" setback will affect the handling very much, if any at all? There will be ten less pounds on the front because of SLP pipe. Thanks for your input.

 

[Ron]

Gerrman
I am only going to set the suspension back 1". The rest of the difference in the new track length will be made up in the rear wheels. Ron, do you think a 1" setback will affect the handling very much, if any at all? There will be ten less pounds on the front because of SLP pipe. Thanks for your input.[/quote]

I don't know....but 1" is a lot on a sled that's already rider forward in design. I wouldn't do it unless it's easy to go back to stock. Are you going to move the mounting position in the tunnel back one inch in front & back or are you going to change the mounting position an inch forward in the rail front & back? I guess you could move the mounting position in the tunnel 1 inch & then adjust the new position in the rail on the rear by going back 1 inch with the Holz instead of 2 inches. Too late at night, getting brain cramp.
I did some checking again on the center extro ice problem. It has happened on 163's too. Carl's had 2 customers report one incident each of ice build up last year. I'm guessing this would be about 2-3% of sleds they sold with the center extro, not insignificant. Can't find any one that knows the actual cause & nothing from Polaris-yet. It obviously has something to do with the tunnel cooler and certain snow conditions. Still very early, maybe Polaris will have something to say soon....they monitor SW posts & have had complaints through customer service. Anyone that hasn't complained directly to Polaris might want to make the call & ask for answers.

 

[gerrman]

Ron

I don't know....but 1" is a lot on a sled that's already rider forward in design. I wouldn't do it unless it's easy to go back to stock. Are you going to move the mounting position in the tunnel back one inch in front & back or are you going to change the mounting position an inch forward in the rail front & back? I guess you could move the mounting position in the tunnel 1 inch & then adjust the new position in the rail on the rear by going back 1 inch with the Holz instead of 2 inches. Too late at night, getting brain cramp.
I did some checking again on the center extro ice problem. It has happened on 163's too. Carl's had 2 customers report one incident each of ice build up last year. I'm guessing this would be about 2-3% of sleds they sold with the center extro, not insignificant. Can't find any one that knows the actual cause & nothing from Polaris-yet. It obviously has something to do with the tunnel cooler and certain snow conditions. Still very early, maybe Polaris will have something to say soon....they monitor SW posts & have had complaints through customer service. Anyone that hasn't complained directly to Polaris might want to make the call & ask for answers.[/QUOTE]

I am going to move 1" back on the tunnel mount holes and make new rear hangers for the rear with the stock and 1" setback holes. This will allow an easy return to stock position if needed.

 

[deepdiver]

No never had ice build up but my sled goes in to thaw after nearly every ride. I saw the posts on ice build up last year too, don't know that it was a huge issue. Ugly when it happened, maybe just the right combo of wet heavy snow then turning to freezing temps??? Maybe a gradual build up???

Hey Ron...you are spot on in re: to the ice build up. Had it happen a few times last year as did my riding poartner on the same days. Comes from soft snow and just cold enough to freeze. The center driver does not have enough clearance in deep snow to eliminate the heavy snow(Heavy key word) usually will happen after riding in deep snow and then stopping for a few minutes. The ice was built up over 3/8" ontop of the driver cogs.

Or being in deep and then a slow ride for a bit. I suspect that the driver stays slightly warm due to friction and then when stopping with heavy snow it freezes..just like you said. Rumbles like a freight train when bad...have to lay her on her side and ice pick the heck out of it.

If you catch it soon enough you can slam the throttle a few times and it usually cleans up.

The trick we found is while on the sled deck reach under and spray the cra_pola out of nthe driver with heavy duty silicon. No problems ever again after we started doing that...I thought of that as I used to do that to my 20yr old snow blower to keep heavy snopw from clogging the shute.

this is a 5 sec. fix..