Have a 151 track, suspension bottoms out and won't rise back up. Checked springs for max. tension & they seemed to be ok.

Removed rear shock....it has some compression in and out, but just stays in one position.

My question.....is the shock suppost to be pressure loaded in the out position? This would help the springs keep the suspension up too!

Fixed last week......Results were ......Greased all 3 zerts, and spun bolts so grease surrounded all moving parts. Bolts had crusty dirty spots where there was no grease. Also put sled on level floor. (removed dolly's). Suspension won't work on dollys. Horray.....

Have a 151 track, suspension bottoms out and won't rise back up. Checked springs for max. tension & they seemed to be ok.

Removed rear shock....it has some compression in and out, but just stays in one position.

My question.....is the shock suppost to be pressure loaded in the out position? This would help the springs keep the suspension up too!

The springs are what makes the suspension work - the shocks just keep it from moving too fast. Check the springs really closely and make sure they are installed correctly and nothing is broken. Sometimes a broken spring can be hard to spot.

Have you repositioned the suspension at all? A friend of mine installed a new rear suspension (aftermarket) in his Nytro MTX (155") and was having trouble getting it positioned correctly. If the mount points are off by even a little bit it won't work right. His would do the same as yours - drop to the floor and not come back up.

Actually that reminds me - do you have it flat on the ground or up on dollies/rollers? If I have mine on rollers (little platform with wheels under the track to move it around) it does the same thing. This is ok - it won't do it flat on the ground. The new suspensions can do some funny things with weight transfer if you only support part of it.

Good Luck!
dave

great post like it thanks for it

The answer to the last part of your question is, yes a good shock should provide *some* pressure and naturally move out to the extended position. That will contribute to keeping the suspension up.

But Dave is 100% right, it should still work basically the same with no shock at all. If this is happening on flat ground (no dollies), something is wrong, either broken or put together wrong. If you can't figure it out, take a good pic and post it here. This is not happening because the shock is worn out. My shocks are all worn out on all my sleds and I don't have this problem with any of them.

I've also done several custom skid installs/moves and I haven't seen this, but that could certainly do it. I would like to see a pic. It should not stay compressed even on the lightest spring settings. I only use the lightest spring settings on the rear torque arm, without exception. Don't forget to check the front torque arm spring (front of the skid), if it's broken or out of place (or adjusted too soft, or restricted by a limiter strap) that will put all the weight on the rear spring.

My 2 cents, especially on an RMK, I would run the ski springs at 3/4 to full stiffness, the front skid spring at full stiffness, and the rear spring at the absolute softest. All limiters should be at their absolute longest setting...shortening the front limiter for more ski pressure is a huge mistake on a mountain sled, but it's a very common tuning mistake for rookie powder riders. The single most important thing for powder is weight transfer - lifting the skis when you accelerate. The center shock (front of the skid) must be at full extension and have plenty of spring force to act as a "see-saw" - when you limit or soften that spring you prevent weight transfer. This is often desirable for a trail sled, but not for powder.

The setting of the ski springs is less critical, but I like them stiff to absorb big hits and the carbides seem to hook up better on trail - it's a slight compensation for all that weight transfer when you aren't in powder. My ride is still very soft most of the time because the weight transfers back to that soft soft rear spring and it absorbs almost everything.

Thanks......Rear shock does not extend out on it's own.
But does have compression. 1900 miles on it. Probably
should replace it, but hate parting with $400 right now.

Took off of dollys & greased suspension, works great.
,

Thanks......Rear shock does not extend out on it's own.
But does have compression. 1900 miles on it. Probably
should replace it, but hate parting with $400 right now.

Took off of dollys & greased suspension, works great.
,

A bare shock is not supposed to extend out on it's own - it is just supposed to resist moving in or out. The springs are what push things around. If you have a coil-over shock (spring wrapped around outside of the shock) and IT isn't extending on it's own the spring is shot. However the springs usually last longer than the shocks so if the spring is done the shock is probably done as well.

I am not familiar with polaris - is that a rebuildable shock?

I have 4150mi on mine. I haven't looked too closely at them as I don't want to spend the $2K for the set of new ones I am looking at... :tounge:

My shocks are not rebuildable so I have no option but to buy new ones. The new ones I get WILL be rebuildable - much cheaper to get new valves and oil put in than to buy a new set.

I have been spending a lot more time off trail the last couple of years so it isn't quite as important to have good shocks. I think I will try and squeeze one more year out of mine then decide what to do. Maybe tear the entire machine apart and fix everything, maybe see if I can talk the wife into letting me get a new one... :wink:

dave

Hmm - well the gas shocks that I installed on the Mod last summer definitely do extend out on their own - slowly. That's how I remember it anyway...sheesh who knows anymore. I put a new Kimpex Pro Gold gas shock on the front torque arm and a new SPI gas shock on the rear. They are not rebuildable but I got them cheap, and I feel that it did give a slight upgrade to ride quality. This may be one of the differences between gas and hydraulic shocks - gas shocks are definitely pressurized, it only makes sense that they would extend on their own. Hydraulic shocks don't - I'm pretty sure about that. Hey, I honestly don't know!! At any rate, I wouldn't replace one unless it is broken/seized, or you can really really afford it. If you have the stock shocks on the skid, they are probably hydraulic.

The low end shocks that Polaris uses are not gas filled and won't extend on their own. Gas shocks will, but are way more expensive. The low end OEM shocks on the 2006 were pretty lousy, I had a buddy that bought a 900 RMK in 2008 new in the crate and the rear shock was already bad with zero miles. (I think they were Ryde shocks, I have a set in my garage to look at when I get home in a few days.)

Fox or Walker-Evans will last a lot longer and are usually rebuildable. You can find a Kimpex or Parts Unlimited shock for a lot less, but they will probably wear out in a year or two, depending on your riding style.