Facebook Pixel

Tested: Dalton Industries Quick Adjust Cam Arms


EDITORS NOTE: This test on the Dalton Industries Quick Adjust Cam Arms was first published in the October 2023 issue of Snow Goer in our Cold Tested department. In that regular department, we put aftermarket gear, parts and accessories to the test and share the results. Enjoy. To see more tests like this on a timely basis, subscribe to Snow Goer here.

The popularity of mountain snowmobiling has caused some well-heeled riders to buy one specialty mountain sled for western riding adventures and a separate “short-tracker” for flatland trail journeys back home.

Of course, not every sledhead can afford such luxury (or wants to spend their hard-earned cabbage that way). They own one sled – perhaps an extreme crossover – that they trailer back and forth.

Fuel injection has made this tactic less problematic – changing carburetor jets is no longer required. But one issue remains. To keep a sled’s engine dialed into its powerband, a rider of a Polaris, Arctic Cat or Yamaha will typically want heavier flyweights in the primary clutch to properly load the engine in the flatlands (where abundantly available oxygen allows the engine to make more horsepower), and lighter weights at altitude (where oxygen-starvation results in diminished power). Modern Ski-Doos use a different system.

Buying another set of factory flyweights is certainly an option. But what if you ride in more than two locations? If you sometimes ride in the flatlands at home, then in the Black Hills (with riding altitudes of about 4,000-6,000 feet), other times at your buddy’s place in Wyoming (riding between 7,000 and 9,000 feet) and still other times chase 14,000 peaks in Colorado, you’d need many different flyweight sets.

Or you could get one set of adjustable weights, like the Quick Adjust Cam Arm system from Nova Scotia-based Dalton Industries. After hearing success stories from friends, we ordered a set of Dalton QAP (Quick-Adjust Polaris) flyweights to use on our 2023 Polaris 850 Switchback Assault 146.

Our focus was altitude adjustment, but the Quick Adjust system is equally as handy for folks modifying their sleds or otherwise fine-tuning their clutching.

Dalton: Choose & Install

Our Switchback came from the factory with Polaris 10-74 (approximately 74-gram) flyweights in the P-85 primary clutch. Ripping down ditchlines and across farm fields in Minnesota, the power of the 850 Patriot engine was always right on tap.

Those flyweights (also commonly referred to as “ramps,” “cam arms” or simply “weights” or “arms”), though, would have been too much for the engine to pull peak RPM on our planned trip to the West Yellowstone/Island Park area. Typically we’ve just bought a set of 10-66 (approximately 66-gram) factory flyweights and installed them before the trip.

This time we went to the Dalton Industries website and selected the brand’s QAP-3 kit. They allow adjustment between 66 grams and 73.5 grams, depending on which inserts were installed in the deep hole in each flyweight.

When the kit arrived, it was well organized and had complete instructions. It included three flyweights that matched the profile of the stock Polaris weights, plus three baggies that each held six exactly weighted set screws of varying lengths. Each set screw was painted with Loctite.

Lining them up on the bench, each baggie included set screws that were 1-, ¾-, 5/8-, ½-, 3/8- and ¼-inch long. Respectively, they weighed 4.3 grams, 3.1 grams, 2.5 grams, 1.9 grams, 1.3 grams and 0.7 grams, per Dalton’s instructions. I own my own gram scale and doublechecked: I found the Dalton specs to be right on the money.

For the range offered by the QAP-3 kit, the flyweight with no inserts weighed 66 grams. For sea-level conditions, we needed to get each flyweight close to the stock 74 grams. To do so, we screwed the ¼-, 5/8- and a 1-inch set screws into the tap-threaded hole near the head of each flyweight, using the Dalton-provided Allen wrench. Dalton’s instruction sheet included math for all combinations – in our case, the three screws added 7.5 grams of weight.

Once the three flyweights were prepared, we installed them into the P-85 clutch. To eliminate the clutch’s spring pressure, some folks might remove the clutch cover for this step. Being comfortable with working on clutches, we partially compressed the spring by hand and then strategically inserted a 3/8-inch socket extension to hold the spring pressure at bay so we could remove the stock flyweights and replace them with the Dalton units.

With the Dalton flyweights in place and set at 73.5 grams, we noticed no discernible difference in the flatlands from our stock 74-gram weights. The sled was reactive and fun, as the clutching properly loaded the motor.

Soon it was time to prep our sled for the trip out west. Without even compressing the clutch spring, we were able to reach into the exposed end of each flyweight with our Allen wrench to spin out the little set screws one at a time. Then we rotated the clutch by a third of a turn to access to the next flyweight end and it again, twice. The process took mere minutes.

We placed the set-screw inserts we removed back in their respective baggies. Now the sled would over-rev its powerband if used at sea level. But when we got out to our high-altitude destination, the engine climbed into its 7800-8000 RPM powerband expertly when we were shredding powder.

Five days later, after we trailered back to the flatlands, we popped open the side panel, removed the clutch guard and carefully re-inserted the little set screws that we had removed before our trip. Within minutes, our sled was ready for flatland ditch riding again.

The Overview

Dale at Dalton insists he is not a clutch-tuning pro, and he doesn’t offer tuning advice. Instead, the company sells its flyweight systems to dealerships and performance shops that are clutch tuning pros – while also selling them to anybody who wants to give it a shot.

I’ve done enough clutch tuning to know that a general rule of thumb is to drop about a gram of weight per thousand feet, but this can vary by manufacturer and model. Ultimately your experience, tachometer and acceleration-feel will tell you when you’re closest to the ever-elusive perfection with your clutch setup. To be clear, those truly chasing perfection may also be swapping helixes and springs.

But through utilizing a quick-adjust system like Dalton’s, we were able to very easily dial-in and adjust our flyweights without pulling apart the clutch, and without owning a plethora of individual weights. And the durable Dalton weights can be kept and utilized on other sleds in the future.

Editor’s Note: Every Snow Goer issue includes in-depth sled reports and comparisons, aftermarket gear and accessories reviews, riding destination articles, do-it-yourself repair information, snowmobile technology and more. Subscribe to Snow Goer now to receive print and/or digital issues.

Leave a Reply

Your email address will not be published. Required fields are marked *