Front Shocks: Expert vs. QS3-R

bailer

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Just wondering how the Expert package front shocks compare to the BRP accessory Fox 1.5” Zero QS3-R’s with regards to spring rate?
 

NHRoadking

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I think the Expert shocks have the new lighter springs.
 
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Have run them both, and feel the 2020 expert package stock front KYB shocks are the best stock (non piggyback style) shocks available on a doo to date.

Installed the Fox QS3R fronts a few weeks ago and it's a far less a drastic improvement over the SP shocks that I've had in the past from upgrading to Fox. I would say the front shocks on the expert are very ridable in compared with past options, but just doesn't have the adjustability of the QS3R if that's a priority for you. Would generally say that when comparing stock settings, the stock KYB feel a little stiffer than the QS3R in factory spring preload (with no rebound/dampening adjustments).

The rear KYBs that come stock on the 20 are good, but still quite limited by the stock rear torsion spring design. Fox Evols really shine in the rear skid. I stuck with the air shocks the toms torsion spring delete kit on my 20.5 850T. Just prefer how it rides compared to stock, especially with the ability to adjust the air pressure of rear track shock for the really deep days and when I want to keep the front end down which is harder to do with the turbo in stock form unless limiter is on short. Have also found that after changing to Fox rears I can run a looser limiter strap while still keeping skis relatively low the ground on climbs.

In summary, the 2020 expert handles REALLY well stock. Shocks are super preferential and expensive, so I'd suggest trying the expert in stock form before doing anything to it. You might be surprised (I was) about how well it's setup right from the factory. It's really a pull and go rig.
 

Devilmanak

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I agree. The ski shocks on the Expert are really really good. Better than a lot of expensive aftermarket that I have run in the past. Spring rate is soft, but valving is very very good. Crank the preload to 4 after break-in and they are great. Rears are not so much, but a lot better than X Models. I am full crank on the knob on both sleds and they are soft. It has taken me a lot of years to figure it out, but proper preload on ski shocks makes a HUGE difference on Doos. You would think that a soft shock would make for better sidehilling, but it is the opposite. The G4 likes a lot of preload in the front for predictable one-ski-ing. Doos come on 1 for preload on skis, I tried a one ski run up the trail during break-in, thought the sled was broken. Now on 4 for preload, I can ride for miles on the trail, left and right corners, easy peasy on one ski. And yes, I ride in the deep. :)
 

Norona

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Have run them both, and feel the 2020 expert package stock front KYB shocks are the best stock (non piggyback style) shocks available on a doo to date.

Installed the Fox QS3R fronts a few weeks ago and it's a far less a drastic improvement over the SP shocks that I've had in the past from upgrading to Fox. I would say the front shocks on the expert are very ridable in compared with past options, but just doesn't have the adjustability of the QS3R if that's a priority for you. Would generally say that when comparing stock settings, the stock KYB feel a little stiffer than the QS3R in factory spring preload (with no rebound/dampening adjustments).

The rear KYBs that come stock on the 20 are good, but still quite limited by the stock rear torsion spring design. Fox Evols really shine in the rear skid. I stuck with the air shocks the toms torsion spring delete kit on my 20.5 850T. Just prefer how it rides compared to stock, especially with the ability to adjust the air pressure of rear track shock for the really deep days and when I want to keep the front end down which is harder to do with the turbo in stock form unless limiter is on short. Have also found that after changing to Fox rears I can run a looser limiter strap while still keeping skis relatively low the ground on climbs.

In summary, the 2020 expert handles REALLY well stock. Shocks are super preferential and expensive, so I'd suggest trying the expert in stock form before doing anything to it. You might be surprised (I was) about how well it's setup right from the factory. It's really a pull and go rig.
This is so well said, and I agree exactly, as I have both the stock and Coil Overs in exact similar sleds
 

BirdmanID

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I agree. The ski shocks on the Expert are really really good. Better than a lot of expensive aftermarket that I have run in the past. Spring rate is soft, but valving is very very good. Crank the preload to 4 after break-in and they are great. Rears are not so much, but a lot better than X Models. I am full crank on the knob on both sleds and they are soft. It has taken me a lot of years to figure it out, but proper preload on ski shocks makes a HUGE difference on Doos. You would think that a soft shock would make for better sidehilling, but it is the opposite. The G4 likes a lot of preload in the front for predictable one-ski-ing. Doos come on 1 for preload on skis, I tried a one ski run up the trail during break-in, thought the sled was broken. Now on 4 for preload, I can ride for miles on the trail, left and right corners, easy peasy on one ski. And yes, I ride in the deep. :)
Can you share your riding weight?
 

NHRoadking

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I agree. The ski shocks on the Expert are really really good. Better than a lot of expensive aftermarket that I have run in the past. Spring rate is soft, but valving is very very good. Crank the preload to 4 after break-in and they are great. Rears are not so much, but a lot better than X Models. I am full crank on the knob on both sleds and they are soft. It has taken me a lot of years to figure it out, but proper preload on ski shocks makes a HUGE difference on Doos. You would think that a soft shock would make for better sidehilling, but it is the opposite. The G4 likes a lot of preload in the front for predictable one-ski-ing. Doos come on 1 for preload on skis, I tried a one ski run up the trail during break-in, thought the sled was broken. Now on 4 for preload, I can ride for miles on the trail, left and right corners, easy peasy on one ski. And yes, I ride in the deep. :)
Are the rear shocks on the Expert the same as those on the Freeride?
 

NHRoadking

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No. Pro 40s in the rear of a freeride.
You're right.

I checked Doo's website and the Freeride has KYB Pro 40s in the skid and the Expert X has an HPG Plus and KYB Pro 36.

I wish Doo would let us choose from at least two shock packages when we spring order.
 
Feb 7, 2009
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You're right.

I checked Doo's website and the Freeride has KYB Pro 40s in the skid and the Expert X has an HPG Plus and KYB Pro 36.

I wish Doo would let us choose from at least two shock packages when we spring order.
The options in the accessory book would be nice to have from the factory. I'd pick the QS3 Air shocks.

It would also be great if the weights of shocks were given as well.
 

toms

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The main improvement for the 2020 expert sled from the KYB ski shock was the Kashima coat. The valve spec was same from previous years, but they did add the same coating technology Fox has been using for years, which helped reduce friction internally. For the 2021 season Fox aftermarket will have new internal technology that will help with both small bump comfort, as well as harsh top outs. The Fox shocks will also be lighter for next year. This technology is not being used by BRP for their Fox aftermarket shocks for next year.
 
Jan 4, 2015
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The main improvement for the 2020 expert sled from the KYB ski shock was the Kashima coat. The valve spec was same from previous years, but they did add the same coating technology Fox has been using for years, which helped reduce friction internally. For the 2021 season Fox aftermarket will have new internal technology that will help with both small bump comfort, as well as harsh top outs. The Fox shocks will also be lighter for next year. This technology is not being used by BRP for their Fox aftermarket shocks for next year.
Expert is valved stiffer than previous models...
 
Aug 12, 2018
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The main improvement for the 2020 expert sled from the KYB ski shock was the Kashima coat. The valve spec was same from previous years, but they did add the same coating technology Fox has been using for years, which helped reduce friction internally. For the 2021 season Fox aftermarket will have new internal technology that will help with both small bump comfort, as well as harsh top outs. The Fox shocks will also be lighter for next year. This technology is not being used by BRP for their Fox aftermarket shocks for next year.
Kashima coating has nothing to do with the KYB ski shock shaft... which is not kashima coated. This is all about valving stiffer as Answ3r noted.

I wish people would stop mentioning lightweight (we're talking a few pounds difference) with respect to shock upgrades. We are riding sleds that weigh 450lb+/- bone dry.
 

NHRoadking

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Kashima coating has nothing to do with the KYB ski shock shaft... which is not kashima coated. This is all about valving stiffer as Answ3r noted.

I wish people would stop mentioning lightweight (we're talking a few pounds difference) with respect to shock upgrades. We are riding sleds that weigh 450lb+/- bone dry.

This is what Doo's website says about the Kashima coating:

"Kashima coating delivers silky smooth shock piston movement for consistent cushioning through every bump - big and small."


Yet, as far as I can tell there is no Kashima coating on the shock shaft, unless it is clear colored.

As for weight, a pound here and a pound there adds up. I'll take the lighter stuff.
 
Aug 12, 2018
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As for weight, a pound here and a pound there adds up. I'll take the lighter stuff.
I agree, and everyone has a threshold for $$$/lb savings. It's usually logical to choose the lighter part options unless they come at the sacrifice of durability. When changing front shocks from KYB to Fox, weight savings did not factor into my decision to upgrade. Rear torsion spring delete is a different story, but that's moving off the original topic (although related).
 

Sheetmetalfab

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This is what Doo's website says about the Kashima coating:

"Kashima coating delivers silky smooth shock piston movement for consistent cushioning through every bump - big and small."


Yet, as far as I can tell there is no Kashima coating on the shock shaft, unless it is clear colored.

As for weight, a pound here and a pound there adds up. I'll take the lighter stuff.
the kashima coating is inside the shock body where the piston contacts it. (Highest friction point)
 

toms

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Expert is valved stiffer than previous models...
Yes it is true they added 1 more shim to the 2020 valve spec, as shown in the picture below. I have shown both the 2019 Valve spec, as well as the 2020 in the picture, with an estimated increase in comp. damping. The rebound and all other shims are same diameter and thickness
But that was not the biggest or best improvement for the shock. Let's just add this shim to all of the 2019 Summit X models and see if you have the same results as the 2020 Expert shock.
 

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toms

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Kashima coating has nothing to do with the KYB ski shock shaft... which is not kashima coated. This is all about valving stiffer as Answ3r noted.

I wish people would stop mentioning lightweight (we're talking a few pounds difference) with respect to shock upgrades. We are riding sleds that weigh 450lb+/- bone dry.
The ski shock shaft has nothing to do with what I was referencing. If you read what I stated , I was talking about the Kashima coating on the shock body. As stated above BRP did add 1 more 1.178 x .008 shim to the compression side. Yes it did help. But the bigger help is in the heavier spring, and the Kashima coat. That is what I stated
And if I am replacing parts, and I can get them lighter, especially when you are talking unsprung weight that is tied to suspension and moving parts on the sled, then I will take it every time, regardless how small the change is. Studies have shown that in optimal conditions, losing 1lb of unsprung mass is equivalent to up to 20lbs of overall sprung weight reduction. In real-world scenarios, this likely is nearer to 6-10lbs but unsprung, and rotational masses should be prioritized as part of your weight reduction activities. I wish people could grasp that!
 

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toms

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I gave out incorrect information on the spring rate yesterday for the 2020 Expert. The information is as follows;
2020 Expert has an 80 lb. spr. rate that is 6.81" wire diameter and 413.6 gr. weight and roughly 8" in length
2020 X and 2019 X have an 80 lb. spr. rate that is 7.29" wire diameter and 497.4 gr. weight and slightly over 9" in length.
 
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