Pen Spring Mod

[Den72]

It seems to me that this mod shortens the length of the travel. With that being said what are the benefits of this mod??

Is it worth doing?

[punkindrublik]

It's a gimmick. Just get good shocks.

[ScaleLifeNewbie]

I personally like running no springs rather than pen springs. With no springs, your truck will ride very low but still have all travel. It’s a win-win in my books.


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79 F150 SCX10 ii
TRXWalker

[Den72]

Originally Posted by ScaleLifeNewbie

I personally like running no springs rather than pen springs. With no springs, your truck will ride very low but still have all travel. It’s a win-win in my books.


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79 F150 SCX10 ii
TRXWalker

Do you just use a heavy weight oil?

[OnTheTrail]

The benefit is it can lower your ride height and thus lower your center of gravity. Because the springs inside are "slightly" pulling down on the shock to get to this ride height, it also can keep the shocks from extending on extreme side-hilling, thus helping to prevent a roll over.

And you are correct, you do loose some down travel in the shocks because even at full extension, the inside spring collapsed on itself does take up some room.

[themountain]

Suspension: "Droop" (The What, Why, and How)

[ScaleLifeNewbie]

Originally Posted by Den72

Do you just use a heavy weight oil?

I run the Axial 30wt that came with my RBK. I’ve never gotten really deep into the spring tuning lol. It sits so low my links are angled up towards the back if that makes since.



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79 F150 SCX10 ii
TRXWalker

[Den72]

Originally Posted by OnTheTrail

The benefit is it can lower your ride height and thus lower your center of gravity. Because the springs inside are "slightly" pulling down on the shock to get to this ride height, it also can keep the shocks from extending on extreme side-hilling, thus helping to prevent a roll over.

And you are correct, you do loose some down travel in the shocks because even at full extension, the inside spring collapsed on itself does take up some room.

So in a nut shell you lose clearance and articulation? But you gain the ability to climb 45 to 60 degree angles without rolling over backwards?

[Den72]

Originally Posted by ScaleLifeNewbie

I run the Axial 30wt that came with my RBK. I’ve never gotten really deep into the spring tuning lol.


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79 F150 SCX10 ii
TRXWalker

This is where I struggle and hence the reason I choose RTR! Way to many variables!!!

[ScaleLifeNewbie]

Originally Posted by Den72

So in a nut shell you lose clearance and articulation? But you gain the ability to climb 45 to 60 degree angles without rolling over backwards?

Pretty much. That’s why I don’t like it. I get the best of both worlds with no springs. Lower cg but still have full travel.

Easiest thing to do is just try both and see which you prefer. It’s not like you can’t put the springs back on if you don’t like it. I tried both and found no springs work best for me.


_________________
https://www.instagram.com/island_crawlaz/

79 F150 SCX10 ii
TRXWalker

[Den72]

Originally Posted by ScaleLifeNewbie

Pretty much. That’s why I don’t like it. I get the best of both worlds with no springs. Lower cg but still have full travel.

Easiest thing to do is just try both and see which you prefer. It’s not like you can’t put the springs back on if you don’t like it. I tried both and found no springs work best for me.


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79 F150 SCX10 ii
TRXWalker

RC life is never simple, LOL!! For everything you try to improve you must always sacrifice something else!

[indybama]

Trial n error, thats half the fun lol. I dont run the pen mod. I fully extend my shocks n run the adjust collar down til the spring just barely moves freely. Seems to b a good ride height n plenty of articulation. But thats just my opinion. Think im runnin 30 or 40 wt in my traxxas gts shocks.

[Greatscott]

The spring mod acts as a dampened limiter, and is just another way to tune your shocks. It certainly has its place, but certainly is not for every situation, but certainly is not a "gimmick".

I am using the pen spring mod on my Enduro to lower the rid height of the rig, but to give a bit more articulation than shock limiters provide. This is a C1 rig, and using this mod lowers the suspension so that the ride height looks proper for the body. And, of course, it helps with CG. I could have gone with an additional 5mm or so of limiting, but that would have killed a lot of the articulation.

Untitled by Scott O, on Flickr

Untitled by Scott O, on Flickr

[Panther6834]

Thought I'd add my "two cents worth"...even though, being still somewhat new to crawling (tho, I did, at least, make it to National last month), mine might only be worth "one cent". In addition to the already-stated 'positive' comments about the open spring mod, it would also allow you to start with longer shocks.

For example, everyone who purchased the Capra kit agrees that the included 95-96mm shocks are to long. Most people (myself, included) replaced the stock shocks with shorter 90mm shocks. Had I thought about it then, another way to resolve the 'problem' would have been to incorporate the pen spring mod. This would have simultaneously shortened the shock length, created negative pressure within the shocks, and dampened full extension.

For my next C3 rig, I'm seriously considering incorporating this into the shocks. The "trick" is found to be determine the best shock length, the best main spring rate, and the best pen spring "rate", so as to achieve am optional compression/extension. My "goal" is going to be 'tricking' the RC's scale shocks to 'behave' the same as the oil dampened shocks found on 1:1 rigs.


~ More peace, love, and kindness would make the world a much better place

[WHITE-TRASH]

I don't waste my time with pen springs, I go straight to the hardware store and get some slightly larger and stronger springs and use a stronger outside spring if needed.

The whole point of it is to hold the shock towards the middle of the travel and act as a sway bar. I run this setup on my pro and sporty. I haven't done it on my scalers since they can't do the same type of terrain to need something like that.