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Discussion Starter · #1 ·
I have a '97 Indy 600 with xtra 12 suspension. When the rear of the sled is pushed down it does not rebound when released. It doesn't seem like it bottoms out but probably close to it. It's been stored for about 6 years probably on it's track. Do I need new torsion springs or shocks or both. Are these OEM shocks gas charged? Thanks.
 

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You should have the Fox gas shocks. I would highly suggest getting them rebuilt. A new set of spirngs wont hurt but should not cause it to do want its doing. I had a '96 MXZ with the same problem everyone said it was the springs but it was a bad rear shock. You should also grease it too, if it had been sitting for that long it needs some grease that should help it to losen up some too.
 

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Discussion Starter · #3 ·
I did grease it and worked the suspension a little. It is not binding anywhere as it falls down when rear of sled is raised. It does not bottom out when jumped on but still sits low. It seems there is lots of upward suspension travel that is not used. The front rear shock may be fox not sure. It does have a spring adjuster for the coil spring. The rear shock is a Gabrial coil over. I'm quite sure these are the original oem shocks.
 

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Originally posted by RED_XCR_440
[br]You should have the Fox gas shocks. I would highly suggest getting them rebuilt. A new set of spirngs wont hurt but should not cause it to do want its doing. I had a '96 MXZ with the same problem everyone said it was the springs but it was a bad rear shock. You should also grease it too, if it had been sitting for that long it needs some grease that should help it to losen up some too.
The shock has very little effect on rebound. If the shaft is bent or binding then yes it will cause the condition you described.
 

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Gas shocks are a load bearing shock. People still think that shocks are only for bump control well that was true of the old hydro shocks NOT gas.
 

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Discussion Starter · #7 ·
I thought the springs support the weight (and rebound) and the shocks dampen the effect. Is my thinking correct for these suspension systems? These shocks are both coil overs and do the coils have any affect on the upward travel - like motorcycle shocks?
How much rebound should an xtra 12 system have, should it rebound to the almost fully extended postion with no weight on the sled?
Lots of questions but I don't want to throw a bunch of parts at this thing to finally solve the problem (if one exists). I gather from the discussion that the torsion springs are at fault?
 

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Well think what you want people minds are obviously not ever going to change about this. I talked this over with a guy who sets up race suspensions in the area. You can Pm and I will give you his number. JB you have no f#&king clue what YOU are talking about! You have never even helped my out all you ever said was uh check you rollers and get your shocks recharged well no chit. He has exactly the same problem as I did on my other sled.
 

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did you actually disassemble the suspension and grease it that way?? More then likely the shafts are seized or rusted and binding. When you grease it through the zerk it doesn't do anything for that problem.
 

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Originally posted by RED_XCR_440
[br]Well think what you want people minds are obviously not ever going to change about this. I talked this over with a guy who sets up race suspensions in the area. You can Pm and I will give you his number. JB you have no f#&king clue what YOU are talking about! You have never even helped my out all you ever said was uh check you rollers and get your shocks recharged well no chit. He has exactly the same problem as I did on my other sled.
Settle down......JB is very knowledgable. JB has been in the suspension/shock business for years and know his ****!!!!
 

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73 vette, extra 12's have lots of sit in. In most cases the 4-6 inches. with the rider on the sled the snow flap about touches which seems like alot but they are trying to be real plush. The springs hold the sled up not the shocks if the shocks played a significant roll in holding the sled up you could not use the low pressure shocks at all. The torsion springs are most likely to lift the sled the last inch or 2 because of there design though the 2 coil over springs also play a role. The extra 12 use a 55 degree torsion. Spring . When they fail they will take a set and have an opening angle greater than 55 degrees. Take the springs off and measure the opening angle. You can take a protractor and draw out the 55 degree angle and the lengthen the lines with a straight edge. There is no limit spec but if you are past 60 degrees I would consider them toast. The 2 coil overs are not usually as big of a problem. They will take a set but you can compensate a bit but cranking up the preload. You can see if they have sagged by measuring the free length and comparing the free length to the polaris coil spring chart. If you do find that the torsion springs are sacked do not use after market. The factory springs are much more predictable.

Shock pressure can be used to fine tune a suspension but it can not carry the the weight of a rider. When making custom shocks I often install shocks with no springs in order to easily move the suspension through the entire range of motion and they alone are not capable of holding the sled at all. A bad shock can hold a suspension down but if the shock can be be compressed and return without binding even if it is a bad shock or has no gas left it is not the shock that is causing the issue. So while checking the torsion springs take the coil overs springs off the shocks and see if they travel smoothly. Since I rebuild shocks it would be in my best interest to tell everyone to just rebuild the shocks and it will solve this but I am most interested in people having their sleds work properly. Springs carry the load and shocks control the springs.
 

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Discussion Starter · #12 ·
Originally posted by jbshocks
[br]73 vette, extra 12's have lots of sit in. In most cases the 4-6 inches. with the rider on the sled the snow flap about touches which seems like alot but they are trying to be real plush. The springs hold the sled up not the shocks if the shocks played a significant roll in holding the sled up you could not use the low pressure shocks at all. The torsion springs are most likely to lift the sled the last inch or 2 because of there design though the 2 coil over springs also play a role. The extra 12 use a 55 degree torsion. Spring . When they fail they will take a set and have an opening angle greater than 55 degrees. Take the springs off and measure the opening angle. You can take a protractor and draw out the 55 degree angle and the lengthen the lines with a straight edge. There is no limit spec but if you are past 60 degrees I would consider them toast. The 2 coil overs are not usually as big of a problem. They will take a set but you can compensate a bit but cranking up the preload. You can see if they have sagged by measuring the free length and comparing the free length to the polaris coil spring chart. If you do find that the torsion springs are sacked do not use after market. The factory springs are much more predictable.

Shock pressure can be used to fine tune a suspension but it can not carry the the weight of a rider. When making custom shocks I often install shocks with no springs in order to easily move the suspension through the entire range of motion and they alone are not capable of holding the sled at all. A bad shock can hold a suspension down but if the shock can be be compressed and return without binding even if it is a bad shock or has no gas left it is not the shock that is causing the issue. So while checking the torsion springs take the coil overs springs off the shocks and see if they travel smoothly. Since I rebuild shocks it would be in my best interest to tell everyone to just rebuild the shocks and it will solve this but I am most interested in people having their sleds work properly. Springs carry the load and shocks control the springs.
jbshocks:

Thanks for the response, that's what I was looking for. It could be that the suspension is ok and as you say has this much sit in. I should ride it first and then determine. If only we had a little snow around here, geeze I did't think I'd be hoping for that stuff! It's been sitting in storage for about 6 years and I just thought the springs were set. I'll take them out and measure per your specs and that will settle the question. Thanks a lot.
 

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Originally posted by jbshocks
[br]73 vette, extra 12's have lots of sit in. In most cases the 4-6 inches. with the rider on the sled the snow flap about touches which seems like alot but they are trying to be real plush. The springs hold the sled up not the shocks if the shocks played a significant roll in holding the sled up you could not use the low pressure shocks at all. The torsion springs are most likely to lift the sled the last inch or 2 because of there design though the 2 coil over springs also play a role. The extra 12 use a 55 degree torsion. Spring . When they fail they will take a set and have an opening angle greater than 55 degrees. Take the springs off and measure the opening angle. You can take a protractor and draw out the 55 degree angle and the lengthen the lines with a straight edge. There is no limit spec but if you are past 60 degrees I would consider them toast. The 2 coil overs are not usually as big of a problem. They will take a set but you can compensate a bit but cranking up the preload. You can see if they have sagged by measuring the free length and comparing the free length to the polaris coil spring chart. If you do find that the torsion springs are sacked do not use after market. The factory springs are much more predictable.

Shock pressure can be used to fine tune a suspension but it can not carry the the weight of a rider. When making custom shocks I often install shocks with no springs in order to easily move the suspension through the entire range of motion and they alone are not capable of holding the sled at all. A bad shock can hold a suspension down but if the shock can be be compressed and return without binding even if it is a bad shock or has no gas left it is not the shock that is causing the issue. So while checking the torsion springs take the coil overs springs off the shocks and see if they travel smoothly. Since I rebuild shocks it would be in my best interest to tell everyone to just rebuild the shocks and it will solve this but I am most interested in people having their sleds work properly. Springs carry the load and shocks control the springs.
uummmmmm, like I said JB is very knowledgeable.....
 

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I have a 99 XLT Classic with the Xtra 12 suspension and just went through the same problem last week. I replaced the torsion springs(larger diameter) and slide blocks and also replaced both shock springs. I had the shocks(Ryde FX) inspected at the local performance shop and they are good, (approx. 2000 miles on them). Everything is well greased. The only thing I did not do, is pull out the shafts and clean them and re-grease, but I have decided to live with the sag and ride as is. The suspension feels smooth and clean, just does not return to full up. At least I know the springs are good. I never bottom out on the trail so it must be ok.
 

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Originally posted by RED_XCR_440
[br]Gas shocks are a load bearing shock. People still think that shocks are only for bump control well that was true of the old hydro shocks NOT gas.
Yes, they are, but try lifting 500 lbs with one? That's what's on a rear suspension when you are riding it. A shock is preloaded to maybe enough poundage to push 5 lbs.
 

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Originally posted by RED_XCR_440
[br]Gas shocks are a load bearing shock. People still think that shocks are only for bump control well that was true of the old hydro shocks NOT gas.
If it WERE a load bearing part of the chassis, why would the springs exist? Springs give ride height and physically hold everything up. the shocks or dampers, simply dampen the motion. If you hit a bump with no shocks, you will see that it will bouce up and down repeatedly until the chassis reaches steady state (in other words, it oscillates until the friction of the suspension slows it down, so on a graph of position with respect to time, it would look like a decaying sine wave). If you have a damper in there, it simply uses hydraulic oil or gas to slow the movement of an internal piston with a certain sized hole (or holes. . ) in it so that the suspension does not keep oscillating. In engineering, it is called a mass-spring-damper system, and if you solve its differential equation, you can estimate its response and its natural frequency (which is the input put into the system which causes an unstable and usually undesired response). Yes the internal pressure will provide a small amount of force to support the chassis, but if it were that significant, the shock wouldn't do its job.

73Vette, check the torsion springs as described by jbshocks. Also, even with good springs, the suspension will not return to the top of its travel (or at least it usually doesn't). If it stops like 1/2 inch lower than if you lift it to the top of its travel, that is usually normal. I think it is probably due to friction in the linkages and shafts You may want to grease all of the shafts and stuff too, as there may be some rust in there causing extra friction.
 
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