Long vs. mid arm lift
03-13-2015, 05:33 AM
#21
JK Jedi
That 1" joint also has a very limited length of threaded shank and needs the longer arm due to it not being able to adjusted out. It does save weight though.
03-13-2015, 08:54 AM
#22
So from what i'm gathering is that i should of just saved my money and went long arm in the first place. Oh well, i'm sure someone will buy my X factor kit, when I upgrade to 60s down the road. I guess ill just enjoy what I can out of it.
03-13-2015, 10:15 AM
#23
Former Vendor
As far as our joints are concerned back when the 1" shank was developed it was an industry leader (most were on 3/4 shanks and heims at the time ~ 2003).
How many failures of our shanks have you seen? We can tell you we have many rock crawling competitors and racers that have used our 1" shanks for years. The track record speaks for itself. Why do we continue to use 1" shanks on the JK Mid Arm and TJ/LJ Short Arm Systems? The answer is easy! 1) They work. 2) Our control arm OD is 1.625. The corners of a 1" jam nut are under the bar O.D. size so as you are sliding down an arm on an obstacle, the jam nut does not become a possible hang up point. Many arms out there using 1 1/4 shanks are smaller than the jam nuts so that to us is a functional issue. 3) There is no need or reason to go to a 1 1/4" shank on them as there are no issues with them.
What we would recommend you concern yourselves with is functionality of joints and how well they work for your application. The reason we pushed to come out with our Pro Series was because of racing applications. A billet machined housing with +/- 30 degrees of usable misalignment out of each joint. We feel this sets the bar pretty high when it comes to control arm joint strength and function. The same misalignment is available in our 1" and 1.25" shank joints.
Why did we go to 1.25" shank joints for the long arms? The answer is simple, we just started making them so we could offer a complete line of Pro Series Joints (3/4,7/8,1, 1.25 shanks) in both right and left hand threads for builders since a lot of racers want to use them. The 1.25" jam nut corners are covered by our 2" O.D. long arm material so there is no issue loss of function for us to offer it.. Strength and adjustment was never a concern.
Our X Factor systems and moving the rear axle back 1" in particular are designed for aftermarket flat fenders which 60+% of the market now use and we endorse for the low center of gravity style builds. When you convert your OEM fenders to an aftermarket flat fender, the actual center line of the wheel well is moved back 1" so this puts it in perfect alignment. Haven't you ever wondered why you look at some JK's with flat fenders and the rear wheels look too far forward? This is exactly why. We address it. This does not require a ton of bump stop either. If you are building your JK as most people do for example, on a 2.5" lift with OEM fenders you would run typically a 35" tall tire with a 2" or 3" rear bump stop. You take the same vehicle and go flat fender, typically you would run a 37" tall tire with the exact same bump stop size as an OEM fender with the smaller size tire.
As far as 1 1/4" shanks yielding a lot more adjustment than the 1" shanks; here is the data behind that and the 1 1/4 shank dimensions below work for our joints as well as other popular joint manufacturers..
1” shank has the following dimensions…
- 2.75” (2 3/4”) long thread length
- .5” (1/2”) thick jam nut
- 1.5” (1 1/2”) minimum requirement for safe thread engagement (SAE Standards 1.5xD)
This means with a jam nut on the joint you will have 2.25” (2 1/4”) of thread remaining.
Subtract the minimum safe thread engagement from that and you are left with .75” (3/4”) of threads that can be safely exposed past the jam nut.
1.25” (1 1/4”) shank has the following dimensions…
- 3.625” (3 5/8”) long thread length
- .6875” (11/16”) thick jam nut
- 1.875” (1 7/8”) minimum requirement for thread engagement (SAE Standards 1.5xD)
This means with a jam nut on the joint you will have 2.9375” (2 15/16”) of thread remaining.
Subtract the minimum safe thread engagement from that and you are left with 1.0625” (1 1/16”) of threads that can be safely exposed past the jam nut.
This means our 1.25” joint has .3125” (5/16”) more adjustment then our 1” joint.
We never want to have a lot of exposed shank as it transitions the shank loading from mostly shear to shear and bending. The bending load is much more severe on the shank of a joint than shear load.
The mid arm to long arm debate really is up to the individual, their budget, their needs etc.
RK
How many failures of our shanks have you seen? We can tell you we have many rock crawling competitors and racers that have used our 1" shanks for years. The track record speaks for itself. Why do we continue to use 1" shanks on the JK Mid Arm and TJ/LJ Short Arm Systems? The answer is easy! 1) They work. 2) Our control arm OD is 1.625. The corners of a 1" jam nut are under the bar O.D. size so as you are sliding down an arm on an obstacle, the jam nut does not become a possible hang up point. Many arms out there using 1 1/4 shanks are smaller than the jam nuts so that to us is a functional issue. 3) There is no need or reason to go to a 1 1/4" shank on them as there are no issues with them.
What we would recommend you concern yourselves with is functionality of joints and how well they work for your application. The reason we pushed to come out with our Pro Series was because of racing applications. A billet machined housing with +/- 30 degrees of usable misalignment out of each joint. We feel this sets the bar pretty high when it comes to control arm joint strength and function. The same misalignment is available in our 1" and 1.25" shank joints.
Why did we go to 1.25" shank joints for the long arms? The answer is simple, we just started making them so we could offer a complete line of Pro Series Joints (3/4,7/8,1, 1.25 shanks) in both right and left hand threads for builders since a lot of racers want to use them. The 1.25" jam nut corners are covered by our 2" O.D. long arm material so there is no issue loss of function for us to offer it.. Strength and adjustment was never a concern.
Our X Factor systems and moving the rear axle back 1" in particular are designed for aftermarket flat fenders which 60+% of the market now use and we endorse for the low center of gravity style builds. When you convert your OEM fenders to an aftermarket flat fender, the actual center line of the wheel well is moved back 1" so this puts it in perfect alignment. Haven't you ever wondered why you look at some JK's with flat fenders and the rear wheels look too far forward? This is exactly why. We address it. This does not require a ton of bump stop either. If you are building your JK as most people do for example, on a 2.5" lift with OEM fenders you would run typically a 35" tall tire with a 2" or 3" rear bump stop. You take the same vehicle and go flat fender, typically you would run a 37" tall tire with the exact same bump stop size as an OEM fender with the smaller size tire.
As far as 1 1/4" shanks yielding a lot more adjustment than the 1" shanks; here is the data behind that and the 1 1/4 shank dimensions below work for our joints as well as other popular joint manufacturers..
1” shank has the following dimensions…
- 2.75” (2 3/4”) long thread length
- .5” (1/2”) thick jam nut
- 1.5” (1 1/2”) minimum requirement for safe thread engagement (SAE Standards 1.5xD)
This means with a jam nut on the joint you will have 2.25” (2 1/4”) of thread remaining.
Subtract the minimum safe thread engagement from that and you are left with .75” (3/4”) of threads that can be safely exposed past the jam nut.
1.25” (1 1/4”) shank has the following dimensions…
- 3.625” (3 5/8”) long thread length
- .6875” (11/16”) thick jam nut
- 1.875” (1 7/8”) minimum requirement for thread engagement (SAE Standards 1.5xD)
This means with a jam nut on the joint you will have 2.9375” (2 15/16”) of thread remaining.
Subtract the minimum safe thread engagement from that and you are left with 1.0625” (1 1/16”) of threads that can be safely exposed past the jam nut.
This means our 1.25” joint has .3125” (5/16”) more adjustment then our 1” joint.
We never want to have a lot of exposed shank as it transitions the shank loading from mostly shear to shear and bending. The bending load is much more severe on the shank of a joint than shear load.
The mid arm to long arm debate really is up to the individual, their budget, their needs etc.
RK
03-13-2015, 10:35 AM
#25
JK Jedi
All my jam nuts dimensions are different. And would leave even less threads available after the nut but its pretty minimal.
Last edited by Maertz; 03-13-2015 at 10:59 AM.
03-13-2015, 10:48 AM
#26
I've had the older style rk joints on my rig for 80k+ without failure or play as of yet. Rk builds a complete lift that flat out works together seamlessly. What actually changes in the geometry (from stock or no stretch to rk stretch) of the suspension if all the parts compensate for said stretch? The fact that the 1" stretch in the rear centers the tire in the wheel well is enough for me. Plus it hasn't caused any issues as of yet and I doubt it will.
'Love blinds', right?
03-13-2015, 11:43 AM
#28
Not me, not a very competent Jeep mod shop owner, not anyone there, including the owners of the long armed Jeeps -- all experienced offroaders -- noticed any ride improvement with the long arms.
I'd expect to hear this from an amateur, not from a manufacturer.
It takes 6" or more lift, for long arms to improve ride feel.
03-13-2015, 11:47 AM
#29
03-13-2015, 11:52 AM
#30
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