Monday, December 26, 2011

Ski Swing Upgrade

OK...I am ecstatic about the improvements to my ProClimbs M800's. I want to tell you about the ski swing upgrade on the vertical adjustable post models. I am increasing the swing on the skis by 18 degrees when measuring from full stop to full stop. I don't feel like I have dramatically increased steering effort although by speeding up the skis I am sure the steering effort has increased some, I cannot feel it though. Without the upgrade I cannot keep the sled balanced to traverse a side hill let alone turn around in the paring lot. I have no control, I am continually fighting to keep the sled going in the direction I want. The sled seems to want to high side me at any moment. When looping out from a climb I have found myself not able to steer sharp enough to keep the sled in the turn and ultimately rolling the sled.

After in stalling the piece in the bottom of the long steering post I can easily traverse a side hill due the fact that now i can counter steer enough to balance the sled. Instantly my ability to balance the sled comes back. Control and precision in my maneuvers are back.



This shows the steering post ready to reinstall in the sled.


This is the steering post before installing machined piece. It is the bottom end of the long post. It bolts to the lower right of the frame underneath and to the right of the throttle bodies. Not to difficult to get out, but must be removed so that the hole can be re drilled for the tie rod end to be reinstalled in the new arm.

This is the piece that extends the arm and increases the tie travel to turn the skis further.


Back side showing recess machined for the ball joint to be installed. I am seeing some of the ball joints coming loose from the factory because they weren't indexed right.


Installed and ready to be drilled.

I choose to modify this arm because I think it is the easiest and most consistent way to duplicate the dimensions. Zbros will be offering a complete replacement steering post that accomplishes the same thing. We could offer a new bell crank, this would require airbox and throttle body removal and add much more work to the process. Another way would be to relocate the holes in the spindles closer to the center pivot. There is no good way to be consistent with this hole location outside of removing the spindles and jigging them in a mill. I believe I have come up with the easiest method with the arm extension. I have been riding this for several weeks and know that it is strong enough and that it works.

Because I have limited time and am away most of the time I suggest that anyone interested purchase this directly from the machine shop. Contact Mountain Valley Machine at 435-563-3632 or their web site www.mvminc.biz. Ask for the Rasmussen steering arm extender. Sells for $95 and includes all hardware needed for installation.

I have tested this on the lay down style post like the 1100t uses. It seems to make the steering feel more twitchy on the trail. I get this feeling anyway with the laydown steering post. It does improve the turning radius and also helps to balance the sled, but the real problem with this steering geometry is that it is not ergonomically correct for stand up mountain riding. Arctic Cat is offering an accessory vertical steering post upgrade. I wonder when mine will come!

3 comments:

  1. I need to clarify the pricing, I was a little premature in listing the price for the steering arm extender. This was a target price and because we chose to upgrade to a stronger material and because of the added machine time, the costs went up. I apoligize for any grief this may have caused. This is a precision piece and will correct your steering radius problems. The new pricing will be $95, follow this link to purchase online.

    https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=86F3VHLMHMCQS

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  2. So...I didn't say anything about grinding the spindle stops, sorry. It should go without saying that if you want your skis to swing further then you will have to grind the stops. To get the full 18 degrees a substantial amount of material will need to be removed. Won't hurt anything, just grind it out. The Zbros post assembly will be built to the same spec as the arm extender that MVM is offering. I did the testing and suggested the dimension that they are using. The Zbros piece is very nice and will reduce a small amount of weight. The MVM piece is good to, but will add a small amount of weight. Which would you rather? They both accomplish the same thing. They both require grinding the spindle stops, about 3/8 to 1/2 inch of material. I am aware that that there is a number of ways to accomplish increased ski swing. This is the straight forward approach that will take the least amount of time. If you choose to use another method that is your choice, but do something because the sled works when the skis turn the right amount. The M8 skis swing 73 degrees and so now my ProClimb does as well. Happy sledding, Bret.

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  3. Does the Ski Swing Upgrade fit the 2012 M1100T?

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