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09 summit rear suspension mod

D
Nov 2, 2008
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Picked up an 09 146” summit for my kid. It appears to have the rear skid mod with a longer front shock and the mounting point moved back on the rails about an inch.
I’ve read all the threads on here about it. How does this mod lighten the front steering? Everyone says it does but I cannot find why. If we lay the front shock down, vs having it in the stock mount on the rail, wouldn’t that take weight off the front shock, thus making it carry less weight and increase heavy steering? I’m just wondering how? I was under the impression that the more the shock lays down, the less weight it would carry. The last thing I want is heavy steering on this Doo. I test rode it in both mounts and can feel it got heavier steering when I moved the shock back or flatter in the skid. I understand this will help the angle of attack but reduces the amount of weight carried by the shock.
Perhaps someone can remember back in the day about this mod.
 

eddy

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Pictures? Diagrams? Moving the rear arm mount on the rails was common, changing the front shock mount was uncommon. Heard of changing the front arm suspension shaft mount point in the tunnel in conjunction with drop rear brackets.
 
D
Nov 2, 2008
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46

This front shock setup is what I have. No rear brackets installed. There is a post toward the bottom on the first page asking about how this mod can reduce ski pressure. Then on the the second page, it must be the inventor of the mod indicating “substantially less ski pressure”. How?

Seems like a whole lot of banter and only 2 people actually did it. Seemed to me a product that was promised to be a miracle and everybody had to have it, then only a few did. While they seemed to get results, it still doesn’t address ski pressure like I said. Longer shock in the front by about 1”, and then move the shock mount back 1” in the rails.
Can someone clarify.
 

eddy

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After seeing what you are doing I think there is another way to improve the rear suspension on that machine. The Ski Doo OEM parts out of a 2013 T-Motion were available as a kit to upgrade the whole rearSuspension. We used that kit very sucessfully. Best overall set up was the combination of 2013 T motion kit with Big Johns T-3 relocate
relocate kit. That was under $500 bucks for everything and updated the whole set up to the 2016 spec.
 
D
Nov 2, 2008
79
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46
We really haven’t ridden the sled at all. Just in a few inches of snow so far. Got it in March with a bad crank but wanted to rip around with what little snow we’ve had left.

Reason for the concern was the fact I’ve ridden some Gen 4 Doo’s and the steering was so heavy, I thought all the linkages were rusted solid but the weren’t of course. Compared to my RMK, they felt so heavy in the front that I couldn’t ride them for more than about 5 minutes.

The sled is for my 12 year old and he knows how easy my RMK steers so I want to get the steering light on this one, but find the information quite concerning. We’d like to start with what we have and tune the best we can and go from there.

Maybe a T motion in the future, but not now since we have not had a real chance to see what it’s made of.

So just to come back to the original question, how does this kit make the steering lighter? It really doesn’t have a ton of sag now as he’s only 125 pounds anyways with both the shocks rebuilt by me in the last 2 miles.
 

eddy

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The whole premise here is to give light steering -correct? Well then Modifying the whole rear suspension is overkill IMHO.
Lengthen the skid's limiter strap, lighten the front ski shocks preload and get a deep keel ski with lots of rocker. Adjust the first two variables until your rider likes it. Use a fairly light spring rate on the three shocks we are talking about
 
D
Nov 2, 2008
79
14
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The skid was already modded when I got the sled so I’m already starting with someone’s thoughts on getting the rear skid closer to 2010 specs, at least that’s what I’ve read.

After my own personal experience with Doo’s, I am just looking to make sure my boy will not suffer as I did with heavy steering. At least this being a 600 will lighten the front. Maybe all the Doo’s I’ve ridden have not been set up properly though. The adjustments make some difference but getting it closer to the RMK steering pressure is my goal. Albeit, I haven’t been able to test this year so maybe it is already good. Sag isn’t too bad with a fresh rear shock. In fact, neither rear shock had ANY oil in them when I got it.
If the steering is heavy, I guess I’ll just shorten the shock, and move it up to hold more weight on the front shock. At least that’s what it appears to me if moved forward. The front shocks are not rebuildable but I have a pair of Walkers from a Polaris that measure really close. I’ll shorten them a little bit if I have to.
 

toms

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The reason Ski Doo lengthened the front track shock was to give it a better approach angle in relation to deeper snow, allowed the end user to substantially lengthen the limiter strap over the shorter shock configuration for 08-09. By moving the shock forward you will end up with less movement in the shock shaft for the front track, and it will plow in the deeper snow. As well for a lighter rider this will result in a very harsh ride. The shock was moved back 3/4", and lengthened slightly more than 1". This proved so successful they continued to run the same configuration until the introduction of the new G5. On the G5, they lengthened the front arm 1/2", and the F/T 0.300.
For the 08-09, the laid back shock offered a overall smoother ride quality for the rider, allowed the sled to get up on top of the snow easier, and by extending the limiter out, made the steering lighter on an otherwise heavy steering. Ski Doo made the limiter strap longer than stock 08 to accommodate these benefits. So if you are contemplating moving the shock back, you will need to replace the limiter strap with a longer version of the 08.
Same for a G4, one needs to lengthen the limiter strap to move away from a heavy steering feel.
 
Picked up an 09 146” summit for my kid. It appears to have the rear skid mod with a longer front shock and the mounting point moved back on the rails about an inch.
I’ve read all the threads on here about it. How does this mod lighten the front steering? Everyone says it does but I cannot find why. If we lay the front shock down, vs having it in the stock mount on the rail, wouldn’t that take weight off the front shock, thus making it carry less weight and increase heavy steering? I’m just wondering how? I was under the impression that the more the shock lays down, the less weight it would carry. The last thing I want is heavy steering on this Doo. I test rode it in both mounts and can feel it got heavier steering when I moved the shock back or flatter in the skid. I understand this will help the angle of attack but reduces the amount of weight carried by the shock.
Perhaps someone can remember back in the day about this mod.
Ok, I'm not a physicist, just a software engineer and I've been riding for 25 years, but wouldn't lightening the load on the front skis increase the "steerability"? Less weight on the front skis = less drag = lighter steering? It makes total sense to me that moving the shock to a more "flat" position would make the steering heavier, there's less load on that shock and more on the front skis. Yes, it does change your approach angle of the track which would theoretically make it go better in powder. Also, a big wheel kit helps too. As for lightening the steering though, I don't see how laying the front skid shock down more would ever help with lightening the steering up... Depending on your skis, I flipped my skis from one side to the other which narrowed my stance a little. That helped with a quicker steer and side-hilling. Simple trick, but it depends on the skis. I had the offset skis. You can also put the narrowing kit on. Also, make sure the shocks are set to your sons weight as well. Not trying to be condescending, just simple things that sometimes get overlooked. " I know I have".
 
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