Recommended amount of Sag on Timbersled Shock Springs?

[Frostbite]

I promise to step back from the keyboard for a while after this one!

The gentleman that owned the snowbike before me weighed about 100 lbs. more than me. The Timbersled shocks I'm sure are adjusted for his weight.

I searched the forum and I can't find anything that recommends a certain amount of ballpark sag when you are sitting on the bike.

I am thinking I should turn down the amount of spring pressure on the shocks on the Timbersled skid a bit but, I don't know how much.

Is there a recommended amount of sag?

I know, I should get out there and ride and adjust accordingly.....I will soon but, I want to get it as close to perfect as possible before riding the bike.

 

[mtn-doo]

There is not a sag measurement. The proper set up is measured by pre-load. You want to loosen the locking collar, loosen the nut by hand. Measure your spring, 8" is the "un-sprung" length, then tighten the nut to achieve 1/2" pre-load, tighten the lock ring. You are looking for 1/4" pre-load on the front spring and 1/4 to 1/2" on the rear spring. I recommend 1/2". A short cut would be to simply measure the spring under tension. 7 3/4 front and 7 1/2 rear.

Hope this helps.

 

[J&L Snowhawk]

Thanks

Good info randy. Another ?? Had to replace front shock on 13 kit cuz it blew apart. New one come with bottom out bumper but thought I read somewhere to remove that. Is that the case? Thanks again

 

[Frostbite]

Wow mtn-doo!

Your response is exactly why these forums are so valuable!

So, rider weight doesn't have any impact on the spring settings?

Should I measure from the very top of the spring to the very bottom of the spring (not including the lock rings) to get the 7 3/4" front and 7 1/2" rear that you recommended?

 

[mtn-doo]

Leave the Jounce Bumper in place. You can measure from the flat "tapered end" of the spring to the same on the other end. That location gives you a flat "top and bottom" location to measure total length. You want to increase pre-load for additional rider weight in the rear shock only. The front needs to stay at 1/4" pre-load. The rear is your adjustment for weight or riders bottoming out. With the "MTN-TAMER" suspension, the rear will collapse and "couple" to the front, via the slide mechanism, keeping your skid flat, or parallel to the ground.

Hope this helps.

 

[Frostbite]

Got it! Thank you so much. I will do it today.

I don't need to remove the weight from the track to do this properly, right?

7 3/4" in the front regardless and the rear starts at 7 1/2" and is adjusted to rider and/or cargo weight to keep from bottoming.

Should I keep loosening the rear shock until I bottom out once or twice and then tighten it up just a hair so I am using as much of the shocks stroke as possible?

Also, I see the front shocks on the bike have been "upgraded" from stock to .50KG fork springs. Is this a good thing?

 

[mtn-doo]

Got it! Thank you so much. I will do it today.

I don't need to remove the weight from the track to do this properly, right?

7 3/4" in the front regardless and the rear starts at 7 1/2" and is adjusted to rider and/or cargo weight to keep from bottoming.

Should I keep loosening the rear shock until I bottom out once or twice and then tighten it up just a hair so I am using as much of the shocks stroke as possible?

No, just set it at 7 1/2 and add a little more from there if you need it.

 

[Frostbite]

OK, sounds good.

What about the front forks? Are .50KG springs OK? I see they were from a manufacturer in Oklahoma if I recall.

 

[mtn-doo]

OK, sounds good.

What about the front forks? Are .50KG springs OK? I see they were from a manufacturer in Oklahoma if I recall.

I would recommend the .56 from Slavens Racing. Amazing. Will totally change tour ride.

 

[Frostbite]

I went out and measured the rear shock springs and let's just say they were really compressed and in the 6" range.

I adjusted them and now I have the front at 7 3/4" and the rear at 7 1/2" but, it seems to be a moving target depending on how much weight is on the bike.

I am guessing that measurement should be taken with the bike ready to ride?

If I lift the rear end up and set it down, the measurement changes every time. I finally just set it down, adjusted both as suggested and left it. Otherwise you end up chasing your tail.

I notice the bike is a lot lower with these shock measurements.

 

[kell8071]

I went out and measured the rear shock springs and let's just say they were really compressed and in the 6" range.

I adjusted them and now I have the front at 7 3/4" and the rear at 7 1/2" but, it seems to be a moving target depending on how much weight is on the bike.

I am guessing that measurement should be taken with the bike ready to ride?

If I lift the rear end up and set it down, the measurement changes every time. I finally just set it down, adjusted both as suggested and left it. Otherwise you end up chasing your tail.

I notice the bike is a lot lower with these shock measurements.

I believe the pre-load is measured with no weight on the suspension, aka track off the ground. Other wise you are loading the spring and getting an inaccurate number.

Kell

 

[Frostbite]

I just went out in the shop and snowbike now looks like a low rider since the rear end is quatted down so much. I am all in favor of a lower seat height but, should it drop it that much?

Yes, I will double check my measurements but, I already checked them several times. 7 3/4" in front and 7 1/2" in the rear.

I have the Fox Zero Pros (I believe) with orange springs on the shocks.

 

[mtn-doo]

??? Pre load will push your tunnel and seat up, not lower it. Better call me.
406-249-1132

 

[Frostbite]

I am the second owner. I purchased the bike with the Timbersled LT kit already attached. The gentleman I bought the bike from weighed 270 lbs. I weigh 170. When I would sit on the bike the rear suspension wouldn't move.

The Timbersled Mountain Horse Kit is a 2012 model as it has a single limiter strap. It has Fox Zero Pro shocks. The springs were tightened down very tightly to just over 6" of compressed length and that really stood the rear skid up.

As I increased the end to end length on the spring it relaxed the tension on the springs, consequently, the rear suspension began to sag. Hence, my low rider comment. I can see it's too low now and before I started it was too stiff. I need the Goldlilocks solution to make it "just right".

That's why my original question was, what is recommended amount of sag when you sit on the seat?

 

[M5-]

So just to deviate off topic slightly, I was going through my bike the other day in preparation for riding this week and noticed my rubber shock bumper is destroyed, I'm surprised it is even still on there as its split right in half. Are guys having problems with these? It must have gotten punished on the 8 miles of whoops we did last week, thanks Randy. Lol. Maybe I need more preload?

M5

 

[Blaser]

I am the second owner. I purchased the bike with the Timbersled LT kit already attached. The gentleman I bought the bike from weighed 270 lbs. I weigh 170. When I would sit on the bike the rear suspension wouldn't move.

The Timbersled Mountain Horse Kit is a 2012 model as it has a single limiter strap. It has Fox Zero Pro shocks. The springs were tightened down very tightly to just over 6" of compressed length and that really stood the rear skid up.

As I increased the end to end length on the spring it relaxed the tension on the springs, consequently, the rear suspension began to sag. Hence, my low rider comment. I can see it's too low now and before I started it was too stiff. I need the Goldlilocks solution to make it "just right".

That's why my original question was, what is recommended amount of sag when you sit on the seat?

Mtn Doo is correct, we do not list a suggested sag measurement like a dirt bike manufacturer will. If we did, it would only realistically apply to a brand new set of springs.
Your springs have had some weight on them, which will require more preload than a new spring; to achieve the same ride-height.

There is a lot more to consider when tuning a rear suspension like the Mountain Tamer than just setting a spring to a certain amount of pre-load. Rider weight, which bike you have, rider style and type, desired ski lift, climbing, racing, hard pack or powder snow, etc are just a few considerations.

In general for your weight, you should end up between 7.00" and 7.75" of spring length on both springs. Both will be different, but likely within that range. Most riders want their suspension plush, yet just stiff enough that it rarely bottoms under harsh conditions. For you, this might require more than one adjustment session to get it dialed in.

Feel free to call us here at Timbersled. We're happy to help you get your Mountain Horse set up.
Brett
208-255-5644

 

[Frostbite]

I hate to keep bringing up snowmobile references but, on the rear suspension I on a snowmobile, I always try to have the front track shock spring a bit stiffer than the rear spring so the sled will more readily transfer weight under acceleration.

Does the same hold true for snowbikes?

I added a before adjusting the rear suspension spring tension and after adjustment picture of my suspension adjustments.

I think the old girl needs some more spring tension but, how much?

I will have to play with it a bit.

Now, if I had only been smart enough to write down the beginning measurements before adjusting anything! Duh!

 

[mtn-doo]

Not with the Mountain Tamer suspension. It is a coupled suspension. You do not want the rear to "squat" and the front shock to "push back". With this suspension, you set a softer front shock, which comes into play independently or after coupling, then a stiffer rear shock for added rider weight etc. Once the rear collapses, it couples to the front and the skid then travels parallel to the ground. No trenching. That is what has made the Mountain Tamer world famous. It is now on bikes. The same suspension without the coupling dial. We used to place shims on the slide mechanism to adjust coupling.

Take a minute and watch this tutorial. It explains and shows the unique characteristics of the suspension.

http://www.youtube.com/watch?v=mUWE3ITfBcI

 

[mtn-doo]

I would start by updating your rear spring. It has a stiffer progressive rate. Then set 7 3/4 in the front and 7 1/2 in the back.

 

[Frostbite]

Thank you SO much!