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USI spx 301s, tips and experiences?

2K views 17 replies 12 participants last post by  buckhunter 
#1 ·
Ive got a pair of SPX 301s coming for my REV and just wanted some input on setting them up, how they work etc.

thanks

also have a pair of precision skis for sale now, complete
 
#2 · (Edited by Moderator)
I have 3 words for you and you don't want to hear them...flex ski + doolys. I've been thru 4 different ski combinations (and I'm tired of buying/selling skis). This is the ski nirvana I've been looking for. Quick rundown in the order I tried them:

precisions-well you know
usi vx301 6" shaper carbide-good corner bite, very little darting, very high steering effort
flex ski with pcs strips 10" carbide-decent corner bite, little less than usis, little darting, reasonable steering effort
powder pros 9.5" carbide- very agressive corner bite, these will never washout on ya, quite a bit of darting and high steer effort
flex ski, removed pcs strips, 8" doolys- good bite in corners, almost no darting, least steering effort of all

Couple other notes, I took the time to set up for every one when I changed skis, varying spring preloads, limiter straps, etc. My toe out is 1/4" total, haven't changed that.

On the PP, I took the time also to shim the front of the ski up to try to kill the nervousness, no dice.

The flex skis without the pcs had excellent bite in the corners and steered real easy also, but darted all over the place, nearly unrideable.

Downside of the flex skis is they have zero floation in powder. The PP were excellent for that, usi somewhere between the 2.

My sled is an 04 renegade 8oo. I hope this helps somebody, I know I've spent a lot of time and money f'in around with it. Good luck.
 
#4 ·
I just installed a set of PX301's, very similiar. After first ride though I made a mistake, but after talking to Rick at USI, I reset my suspension and what a differance. They are Awesome!!! Give him a call at 1-765-423-2984 for your set up questions. He knows his REVs. Good Luck and Good Riding!!!!!
 
#5 ·
Tinman said:
I just installed a set of PX301's, very similiar. After first ride though I made a mistake, but after talking to Rick at USI, I reset my suspension and what a differance. They are Awesome!!! Give him a call at 1-765-423-2984 for your set up questions. He knows his REVs. Good Luck and Good Riding!!!!!
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What Tinman said is right on!!!
 
#7 ·
I called USI and made all the changes they suggested.

1.Crank up center spring
2.Let off rear spring
3.Bend rear of ski up, less keel in snow
4.Move to back hole of ski(cut carbide bolt down)
5.Use round bar 6" rather than shaper
6.Let the limiter strap out

Now the sled is perfect in powder turns on a dime on hard surface and you can trail ride on hard pack without bad arm pump.
 
#8 ·
Buckhunter: could you tell me more about the move to back hole (cut carbide bolt down)? Sounds strange to me, do you mean to mount the ski in the rear of the 3 mounting holes? cut carbide bolt down?
I dont want to back off on my rear springs, im 210-215lbs. without riding gear on and like to jump and ride bumps hard. Also, I dont want to be bending up my new skis. Id love to make the center shock spring firmer, ive tried before with the precision skis and it wont even steer like that. (I can turn the bars sideways and go straight)
What do you do with your front shock spring settings?
Im not going with the shaper bars, Ive got 2 sets of round 6" coming with them.
And let out the limiter more? Man I already wheely up alot.
 
#9 ·
sounds like alot of work to me. I am looking at a set of USI project X skis also but after reading this I belive I am turned off on them. How do you bend plastic ski's up in the back? And cutting carbide bolts off?
 
#11 ·
saltalarev said:
sounds like alot of work to me. I am looking at a set of USI project X skis also but after reading this I belive I am turned off on them. How do you bend plastic ski's up in the back? And cutting carbide bolts off?
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THE SKI AT THE REAR IS FLEXIBLE AT THE TAIL AND THE SKI CONFORMS TO THE BEND IN THE WEARBAR. ALOT OF GUY DO THIS WHEN RACING TO TUNE THE SKI TO THE CONDITIONS. CALL USI THIS ISN'T THAT HARD TO DO.
 
#12 ·
Better than the C&A's because I am thinking of getting a set of Px-301's. Are they the ones you guys are talking about?? I see that they are about 230.00 is that correct? shaper ski's?
 
#14 ·
I have the SPX's on my 03 800 and love them! All I did was loosen the strap one notch and off I went. It is a different animal, light front with acceleration and heavier then most once you let off the throttle. Just took about 30 miles to get used to but now I love them. If you point them the sled will follow!
 

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#15 ·
I put the SPX 301's on, and at first I was nervous. They bit hard, and inside ski lift was bad. I tightened my front shocks up to 3, and the center is close to 2/3, and it rode fine the rest of the day. I didnt think it was that hard to turn. I took the 6" shaper bars off the other day, and bent the back's up a little bit to lift the back of the ski up a little. I'm riding tomorrow so I'll see if it helps with steering effort.

AFter 130 miles of riding, I felt they were a good investment, especially after my buddy was having a hard time in some of the icy corners, reminding me of the precisions.

Eric

cbecc said:
I have the SPX's on my 03 800 and love them! All I did was loosen the strap one notch and off I went. It is a different animal, light front with acceleration and heavier then most once you let off the throttle. Just took about 30 miles to get used to but now I love them. If you point them the sled will follow!

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#17 · (Edited by Moderator)
I love the handling of the USI's, they grab. I purchased 3 sets total for a couple buddies and me.
1 PX for a 800 Gade w/9"shapers
2 sets for 500SS Adrenalines. Ordered 7 1/2" shapers for our SS', but 9" showed up. SPX also showed up because they don't make yellow PX any more, just SPX's and we both ordered yellow.

The skis were OK until I hit the gas. Then the skis lifted and I ended up increasing front shocks to 4th setting and they always grab now. They steer hard, but they turn when you want to turn, so I don't mind. Since I purchased them, I have been told that the USI's don't need the Shapers. They work great with the round bars and steer much easier.

I have two problems that I don't like and have to resolve:
1) The outside of the skis (outside keel or rib) on my SPX are wearing off on the front half of my skis.
2) Inside turn ski lift. The skis grab so hard, it's like riding on rails and the sled leans out.
Between the skis, RipSaw and studs, it doesn't slide at all. Kind of wierd because I use to slide everywhere on my Polaris that didn't have studs, they called me "Duster" because I spun every which way and kicked up snow dust.

The problems may be related because I have a feeling that I don't have the rear shock adjusted correctly. I will try what they said about the rear shocks next time I ride to see if it helps. I have also read that I may want to move my skis to the rear holes in the mounts.

The other two guys are not having any problems with wear, so I am going to contact USI and see what they say.

To bend the "back of the plastic ski up", bend the back of the wear bar up for easier steering, The entire ski is put together by the carbide and nuts. The carbide bolts on the ski & saddle at the same time.
(if you change your carbides, your ski falls off from the saddle)

The next round of carbides will be just round for my USI skis. No more Shapers for them. That sounds like the best way to go for these skis if you want easier steering and better handling.

The other 500SS owner drove his Precisions before swapping and he Loved the USI's over the Precisions. No questions there, that is for sure, USI's beat the Precisions!

(If anyone does decide to stay with the Precisions, buy 6" Shapers for the inside of the skis, they will not fix, but will improve the pushing a bit, better than stock carbides for sure)
 
#18 ·
When you move to the rear of the three mounting holes one of the bolts to your wear bar will not have clearance to where the ski mounts to the sled? Cut the bolt off flush with the nut (about 1/2"). When you have the wear bar off then put it in a vise and bend it a 1/2" up between the rear 4th and 5th bolts. Straighten out the 5th bolt and attach to sled. This should bend rear of ski up and take pressure off the front part of ski. It took me less than 1/2 hour to do this and helped quite a bit.

I used the stock precision rubber, USI said that was fine? The USI's rubber is a harder compound and it seems a little large?

Play with the suspension the less ski pressure the better.

I had my precisions on and snapped a bolt and bent a brackett on my A-Arm, I had a ton of ski pressure and I hit something on the side of the ski. IMO with this setup I had way too much resistance on the front end and with this condition I set myself up for a front end failure?
 
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