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Discussion Starter #1
So how is it that some UTV's get their axles/CV to travel to more severe angles (24 inches of travel etc.)? My 77" long travel XX appears to be limited to about 20 inches of travel in the rear before you have to start worrying about the axle pulling out. Speedsxs has spent a lot of time testing axle setups and they still only offer 20 inches of travel in the rear, with the 77 kit. I would assume 18 inches is the safe limit for stock. From what I read, the axle is always the limiting factor. I realize that shock position and arm length can give you more travel , but it is still limited by axle travel right? I also know that some rigs have certain other clearance issues. But if an XX can function with 24 inches of travel without clearance issues, why does the XX fail in this regard.
 

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Gordon says his new car will have 24" on the 77.
They probably need to visit the new Textron setup with the center slip yoke.

We will see how his car stacks up in the real world.

But you are correct. on a swing arm rear setup, you need enough plunge or slip and enough cage cut for the angles.
If an axle is "pulling out"...it is due to a lack of travel in the axle yokes. The new Textron axle has about 3.5" for the 18 " of travel.
 

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With radius rods the axle stays the same length through the travel and they can handle more but they also kick sideways every time the tire lands.

With the XX trailing arm the axle changes length quite a bit through the travel and the axle can only handle so much but the tire moves straight up and down the whole time.

Travel numbers are like drag race numbers. Bragging rights without a lot of real world relevance.
If you have everything set up right you can run through the big stuff faster and smoother with more control than any other 2-seater out there.
 

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Discussion Starter #4
I wondered about the radius rod difference. But I also saw the post about RG saying that the new speedutv will have 24 inches of travel front and rear. All shocks will also have a 12 inch stroke- this makes me wonder what the Fox XX stroke is? I assume that the trailing arm is the same as their current long travel XX kits, which made me wonder why they couldn't get 24 inches on the current XX version.

I do agree that this rear end design is sweet. In my case, I'm still tweaking my setup. I think I may have to move to a heavier spring set front and rear. My Fox shocks have shock therapy springs that were set for my rig when it was 64 inches. I think I'm running too much preload to reach the correct ride height. The front feels a little too stiff, while the rear still squats more than I think it should under power. I also bottom out in the rear sooner than I think it should.
 

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Discussion Starter #5
FYI: it looks like the XX Fox shock stroke is 8 inches in the front and 10 inches in the rear.
 

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I wondered about the radius rod difference. But I also saw the post about RG saying that the new speedutv will have 24 inches of travel front and rear. All shocks will also have a 12 inch stroke- this makes me wonder what the Fox XX stroke is? I assume that the trailing arm is the same as their current long travel XX kits, which made me wonder why they couldn't get 24 inches on the current XX version.

I do agree that this rear end design is sweet. In my case, I'm still tweaking my setup. I think I may have to move to a heavier spring set front and rear. My Fox shocks have shock therapy springs that were set for my rig when it was 64 inches. I think I'm running too much preload to reach the correct ride height. The front feels a little too stiff, while the rear still squats more than I think it should under power. I also bottom out in the rear sooner than I think it should.
Gordon is trying to keep the travel linear in the shock ...so he needs a longer stroke to gain that. Basically, the angles don't change too much through the stroke. Very smart what he is doing with all 4 shocks the same size with different rates front to rear. The rear (as well as the front I think) probably has a different upper mount point and different angle me thinks.

On paper- his designs make a whole lot of sense- something that nobody else is doing. Can't wait to see how it works.

You may need a ST rework of your shocks for the 77 kit.
,
 

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Discussion Starter #7 (Edited)
I wonder if it is related to the sweep back position of the axle. The current trailing arm sweeps back about an inch in the rear. So the arc places the axel straight at full droop or compression. So 24 inches would require it to be further back, but the CV angle would still be greater.

As far as the front shocks go, I'm sure it is just a matter of shock positioning, as you say.

I'm just in learning mode.

In any event, I hope they make a kick ass machine that dominates the markets and forces even greater competition. We will all benefit.
 

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I wonder if it is related to the sweep back position of the axle. The current trailing arm sweeps back about an inch in the rear. So the arc places the axel straight at full droop or compression. So 24 inches would require it to be further back, but the CV angle would still be greater.

As far as the front shocks go, I'm sure it is just a matter of shock positioning, as you say.

I'm just in learning mode.

In any event, I hope they make a kick ass machine that dominates the markets and forces even greater competition. We will all benefit.
Yes the compound angle has to be taken into consideration when figuring max CV angle. RG could be using a longer or different CV set up a and/or longer axles by moving the end points in or out with a narrower trans or a different bearing at the wheel to get more travel and still be 77"...hence more travel than what you have with 77'' width. Like stated above....DON"T get caught up is the "numbers"....16'' can ride better than 22'' any day set up correctly. Look at what Polaris does with the S...gives you a "usable travel" number far greater than actual wheel travel just to hype the machine!

On a side note if you are gonna get rid of the ST spring kit hit me up I would be interested in buying it.
 

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Discussion Starter #9
I'm more interested in not having the axle fail than the amount of travel. I just got curious as to why RG had such issues getting past 20 inches on their long travel kits- I know they tried. I have a better understanding now.

As far as the springs go, you are the 2nd to ask. I'm pretty sure that I won't need to replace both top and bottom springs, probably just the top coils.
 

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I'm more interested in not having the axle fail than the amount of travel. I just got curious as to why RG had such issues getting past 20 inches on their long travel kits- I know they tried. I have a better understanding now.

As far as the springs go, you are the 2nd to ask. I'm pretty sure that I won't need to replace both top and bottom springs, probably just the top coils.
On a trailing/track arm setup like Po and CanAm, when you go wider you increase travel...because the center pivot point is fixed, pushing out the hub to whatever length. Like an a-arm or swing axle setup. Wider gives more trave with a longer arc..
On the Textron setup, going wider on the rear will not increase travel...only going longer....since the only pivot point is at the front mounts.

Front A-arms...sure- wider is more travel or longer arc with a fixed shock position.
Rear you need a longer swingarm to gain travel with a fixed shock position.
 

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Discussion Starter #11
I hadn't thought about that. In the trailing arm case, a shock with more stroke would increase travel too right?

This made me curious, so I compared the stock arm to the 77. It isn't longer. There was a shim added to the bottom of the shock during the update, so it is a little longer. The shock attach point is identical, except it sets 3 inches further out laterally. This means that the 77 shock doesn't sit as straight as the stock shock. Would the lateral movement of the shock have any impact on travel? If not, the rear trailing arms produce identical travel numbers as stock, right? The front would have more travel though, depending on attach points.
 

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If you had the shock mod done when you did the long travel then the travel of the shock was increased to match the trailing arm. It's not just a shim at the bottom, the shock had an internal spacer from the factory that gets removed for the long travel.

As far as the length of the trailing arm being the same, the important detail is the distance the hub is from the transmission and the length of the axle. That is what gives it the ability to have more travel.
 

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Discussion Starter #13
Apparently, there is a spring removal and machining required on the rear shocks. This gives the rear shocks one more inch of travel. This wasn't done on mine, so I need to get it done or move to a different shock. The front shocks require some internal work too. The King shocks are setup more to task, so the Fox mods only get you part way there.
 

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Hook I have a 72" kit and I have been fighting the travel numbers on the front of my car. The front uses oem cv's and RG axles along with modified internal shock spacers. I measured the oem max droop angles and modified the internal shock spacers to get the same angles as the OEM 64" car. Currently I am cycling 19.5 on the front. I also had to check shaft plunge at full compression and full droop. In a few weeks I will start working on the rear. I expect the rear to be a completely different game as the cv's and shafts are aftermarket. I am more familiar with the 930's cvs and how by clearancing one can get more combined angle. I have a set of axles that went out so hopefully I can experiment with them and learn how they can be modified and what angles they can be pushed to. Have you measured your usable rear travel on the 77" kit?
 

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Discussion Starter #15
The mechanic measured, but I don't have that number. I'm sure it is the same as stock though, because it has the stock stroke. There was a miscommunication with Speed and the qs3 update, so my shocks didn't get the internal work. If the rear shock is properly modified, it should have an additional inch of stroke- this should translate into 20 inches of travel. But I suspect these travel numbers are mythical, based on our last measurements. The Speed King shocks are set at the correct stroke from the start.

What is the stroke on your front shocks?
 

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Discussion Starter #16
So I'm now being told by Speed that the qs3 update does not change the stroke in the rear. And unless my trailing arm length measurements are off, the Long Travel kit /Fox rear qs3 update adds nothing to rear travel. I misunderstood what Todd told me- there is no way to modify the rear Fox shocks for an additional inch of stroke. If you want the real advertised travel numbers (22 Front- 20 Rear), you have to go with the Kings. Although, I can not confirm the King numbers either, because I don't have a set and I am still waiting for the stroke specs.

We are adding the internal qs3 update to the front shocks tomorrow and I will pass on those travel measurements. We will also remeasure the rear. The mechanic has the original measurements written down, but I didn't get them....we only talked about the results.

Again, I'm not hung up on the numbers per se. I'm just in the middle of tuning these shocks and the numbers didn't add up.
 

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What is the internal qs3 update? So far I have modified my valving and internal shock spacer on the front. I have bought the dsc adjusters and I haven't had time to install them yet. I am also looking into a adjustable rebound setup. From what I understand the rear can be modified for more travel due to cv angle and axle plunge. I hear you about the numbers not adding up. I have been down that road and I just couldn't argue with with my tape measure.

This is where I picked up my spacers for the front.

I also put the shock therapy limit straps on to eliminate the harsh slam at full extension.

One thing that I haven't had time to do is measure the real travel numbers on my stock car. I wonder what I will find?

Good luck.
 

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Discussion Starter #18
The internal update requires the removal of a 3" internal spring and replacing it with a spacer. It is supposed to add almost a inch of stroke...which probably translates into a few inches of travel.

FYI, King has part numbers for the XX on their part list. The front shocks show long travel only, but the rear show interchangeable. I can only assume this means they are the same stroke as the stock Fox shocks.

This is consistant with the Speed qs3 update where only the front stroke changes.
 

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Discussion Starter #19
The stroke front and rear is the same after the internal shock mod. There is a 9 inch stroke in the front and rear. There is 19.5 inches of movement from full droop in the front, measured from the top of a 31 inch tire. Any more and it would hit the fender. We didn't touch the shocks on the rear, but I know there can't be more than 18 inches of movement, based on the 2 to 1 ratio to stroke.
 

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Discussion Starter #20 (Edited)
The rear is the same. From full droop, 18 inches has the top of the tire almost hitting the fender. So regardless of real world travel numbers, you run into clearance issues. The actual travel is closer to 17 inches, btw.
 
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