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Shock Setup Tip for reducing Torque Twist

Rich Trujillo

Sr. Product Developer
Vendor
Joined
May 24, 2005
Messages
786
Location
Fontana
PLEASE READ THE ENTIRE POST BEFORE YOU COMMENT :)

Just in case nobody has noticed, our rig has more torque twist than most rigs out there. In fact, i'm surprised nobody has ever mentioned it on every post i have ever made :lmao:

The challenge we have is that the majority of our reduction happens in the center transmission which we used from the Twin Hammers. To get the smaller diff housings and adjust the overall drive ratio for the TH trans, we had to go with a taller ring and pinion ratio. So mechanically we are always going to have more torque twist than other rigs with a lower pinion/Ring gear ratio.

Here is what I have done to reduce the torque twist on my rigs.

I switched to our threaded aluminum shock bodies and modified the stock plastic threaded adjuster collar from the original shocks. I remove the knurled larger section and use the smaller ring to adjust the pre-load on the softer upper spring. Doing this set up, is kinda like running the left rear spring with more preload. The good part is that it allows your rig to sit even at ride height and get stiffer through compression. This is how the "real" dual spring shocks work on my buddies Polaris UTV. I do plan to make this a running change to our rigs in the future but it will take some time before you will see it available.

Now before you accuse me of trying to get you to buy our optional shocks, I'll note you should be able to do this with any optional dual spring type shock or even your stock plastic shocks. Yes you will need to buy a set of VTR233027 for just the Adjuster collars.

Please consider this a tech tip/ Setup tip and yes i know there are different cut gears options out there as well as sway bars, raised upper link locations etc. This is just another option that has worked pretty good for me.

Thanks,
Rich

Here is a link to a video showing how this works aka "Crossover spring gap setup"

https://www.youtube.com/watch?v=QWTLe14Mbm0

40270987261_d7cb1c5ff1_b.jpg


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Very clever! I'll have to give that a shot, I've got an old set of the plastic shocks too.

Actually now that I read through again I'm wondering how this works :oops:
Doesn't using both of the adjuster nuts essentially take the upper spring out of the equation, seems like it would no longer move. Or is the lower adjuster just a stopper of sorts for the lower spring?

EDIT: I think I understand better, this mods allows you to dial in the preload for just the upper spring alone, right?
 
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Nice idea, it creates a travel compression stop for the short upper spring, thus forcing the lower spring to do the work during remainder of shock compression. Thanks for posting Rich, great pictures too! :)

Edit, this mod will benefit any vehicle where you want to isolate and force the firmer spring rate to take over before the shock bottoms out. How to properly do this had been bothering me for awhile, but I'd not found a solution and had forgotten about until you posted. I'd tried all the upper and lower springs and found the firm upper and lower too firm, but when mixed rates were used the softer rate spring ended up doing all the work...effectively negating my use of one firmer and one softer spring. On my mod list now.
 
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Looks to me like the top spring is now just a long stop and the bottom spring is the only one in play....

How is this different from removing the top spring?


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Looks to me like the top spring is now just a long stop and the bottom spring is the only one in play....

How is this different from removing the top spring?


Sent from my iPhone using Tapatalk

Thats what I thought at first too.

So the top spring will still move as I understand it, and as Nate explained its a travel stop so that you can tune how much travel this top spring has.
 
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Thats what I thought at first too.

So the top spring will still move as I understand it, and as Nate explained its a travel stop so that you can tune how much travel this top spring has.



You can tune the lower spring with the custom threaded collar and either remove the upper spring or squish it between two threaded collars. Either way, only the lower spring is in play.


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I’m arguably the dumbest person on this forum and even I can see this is boloney...


Sent from my iPhone using Tapatalk
 
I’m arguably the dumbest person on this forum and even I can see this is boloney...


Sent from my iPhone using Tapatalk

Nate did a very good job of the deeper explanation...the only thing i can say is to try it and you'll see how much different it is from just preloading one spring.

Rich
 
Thanks Nate! That concise explanation helps

You're welcome, always glad to help! "thumbsup"

Looks to me like the top spring is now just a long stop and the bottom spring is the only one in play....

How is this different from removing the top spring?

No, this limits the amount of shock shaft travel utilizing the lower rate short upper spring, then the adjustable spacer (made out of shock collar) forces the higher rate long lower spring into action for the rest of the shock shaft travel. And it's user adjustable, I like it. :)

Thats what I thought at first too.

So the top spring will still move as I understand it, and as Nate explained its a travel stop so that you can tune how much travel this top spring has.

Yes! :)

I’m arguably the dumbest person on this forum and even I can see this is boloney...

Please look closer and imagine it all in motion, it will work. "thumbsup"

Nate did a very good job of the deeper explanation...the only thing i can say is to try it and you'll see how much different it is from just preloading one spring.

Rich

Thanks, and yes to those doubting it go read up on this and/or try it before denying it will work. "thumbsup"

[
 
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Okay I get it now. It took me longer than usual to visualize what is really going on there (long day at work) but boom the lightbulb just went on. I was questioning this at first, but I looked closer and closer and closer. Then I saw the springs moving in unison through the compression cycle, then I saw the mid range travel stop (that's what I'm calling it) stopping the spring isolator at the predesignated location and the lower spring forced into to duty. It's crazy at first I was like "Rich is so full of smoke right now" but I completely see the tuning potential. "thumbsup"

The spring isolator moves freely up to the point of the mid range travel stop.

Nice job Rich. You made me think, I recommend that to everyone.

.
 
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Maybe Rich could post a picture of the shock in it's non compressed state with the compressed pictures above as reference of before and after the isolator hits the stop. That's how I visualized it. "thumbsup"
 
Thanks Ernie and Paul, I too was looking at it at first and thinking what tha heck? Then I looked closer and visualized the shocks moving, suddenly it made sense, great new tuning tool to help TT and suspension tuning in general. Running this should also help climbing wihtout need to run stiffer rear springs than I want, but at an adjustable point of rear end squat/tuck on steep climbs it will force the stiffer springs into action and help prevent truck from tumbling over backwards. :)
 
Swaybar helps immensely and I'm running them too with a nice soft bar that I made. Rich's shock mod is another great tuning tool, that should help TT too.
 
Here is a video link on how this works...again not my idea, just took from 1:1.

Also note, I'm not a designer, i'm a product developer that works with designers. That being said this little tip was found by our race team manager that looked at my Ascender and said...wait a second, these dual spring setup is missing something LOL.

https://www.youtube.com/watch?v=QWTLe14Mbm0
 
I'm anxious to give this a try. I just need to compile a quick list of a bunch of other parts to order along with the part number that Rich gave. Thanks for sharing this tip, Rich.

Hmm... maybe I should use a Vaterra parts order as an excuse to make another attempt to build a V100S Rally car. Maybe Rich has some tips for that kind of conversion that he could post in the RCCrawler Rally thread? "thumbsup"

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