I have installed quite a few new products on the XPT4. Over the next few weeks I will write up a review and my thoughts on some of these products.
First up is Shock Therapy springs:
The XPT comes with industry leading Fox Podium internal bypass shocks. They allow for 22 positions of compression settings. However, as good as they are the stock Polaris springs are the weak link. The factory tender spring stay 100% compressed unless the shock is fully extended.
While the ride quality of the stock setup was ok I felt it could be better. After talking it over with a Shock Therapy and fellow member who already has ST springs I decided to order their 3P kit. At ST advice I did a spring only swap with no re-valving. Unless your racing or doing a lot of high speed racing the stock valving is fine and your basically wasting your money for trail riding applications.
I provided ST my riding style and about how much weight I added and 3 days later I had a box waiting when I got home
I choose the 3 p kit which replaces both front springs and the rear upper spring and reuses the stock lower spring. The kits comes with crossover to convert the stock single rate to a true dual rate spring setup.
The install is fairly straight forward and takes about 30 min per shock. I have a spring compressor but it's too big for these small springs so I used two ratchet straps to compress the springs and swamp them out. Make sure to follow the directions are orientate the springs 180 degrees apart.
The time consuming parts is adjusting the preload collars. ST provides a basic starting point for setting that yield 13.5" of GC. I added a bit more preload because I wanted closer to 17" of GC. Rule of thumb: 1" preload - 2" of GC. First guess was too stiff resulting in 19" of GC. A little adjusting and it's right at 17" front and rear.
The tender springs are very soft and absorb the small hits until crossover kicks in. Then the suspension works on the larger bottom springs. I am still adjusting the crossovers to get them how I like.
I have a good before and after comparison.
First trip on the new machine was to Windrock with a completing stock suspension except a 3" lift kit. I left the front and rear sway bars on and really liked the ride quality. Only a few times did I noticed the sway bar hindering articulation.
Second trip was to Windrock with the ST spring and I removed the lift. I also added Walker Evans sway bar links in the rear. I will do another review of those later. The ride quality is extremely good and the articulation better. These are fairly soft springs so IMO you really need to keep the sway bar hooked up. Chad can vouch for that
Only down side I've seen is the tender springs sometimes rub on the crossover rings and "pop". I'm going to tinker on adjusting them this weekend to see if I can eliminate this issue
IMO, I would say ST springs are probably the best money you can spend and one of the first modifications I would to any RZR.