Just FYI on Revtek lift - dont need rear extended bumpstops

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

Hey folks - just an FYI for those looking at the revtek kit (I posted pics in my other thread) - you dont need extended bumpstops for the rear. I was told this by Revtek but didnt believe it until I actually went to place hockey pucks in myself to limit travel.

Before anyone jumps all over me crying foul - this is what I discovered to back this (remember this is on a KK):

On the Revtek - the new rear spacers (1-1/4") do not have a large hole in the center as the stock rubber isolators did. In other words, the bumpstop will not fit down "inside" the spring perch spacer under compression. The new spacer sits on top of the OEM isolator. In fact, the new spacer actually has a portion that sits just slightly higher and "inside" the spring if that makes sense. (i.e. the spacer created a slightly higher contact point for the bumpstop)

I took some measurements as well (several times to ensure I was correct). On level ground without anything in the rear (equipment, people, etc...) the distance from the bumpstop to the Revtek spacer is 1-3/4". Thats all. I realize the OEM bumpstop might have some compression to it, but not enough to cause problems with fender clearance OR bottoming out and damaging the RSX 17004 shock. If I were to place the 1" hockey puck in there, I would only have 3/4" of compression before hitting (again I measured to make sure). The distance, as it sits now, from the tire to the closest point of contact on the rear fender is nearly 4-3/4". No way the bump stop is gonna compress 3 inches after contact. Also - my RSX17004 has a compressed length, eye to eye, of 15-1/4". As it sits now I measured just over 19-1/2" eye to eye. Again - no way its going to compress over 4 inches (in fact, since the shock is at an angle, it would take a bit more than 4" of vertical compression to net 4" of compression on the shock).

I realize that once I go to a different kit (which I plan on doing eventually) with different springs - I will likely need to limit travel, but in this case with this lift - they are not needed.

HIKJ · **Posted:** Sun Mar 09, 2008 6:40 pm

You have thought this through very well. Seems 100% logical to me.
Just wondering if you come to similar conclusions regarding the front of your Revtek-lifted KK.

tommudd · **Posted:** Sun Mar 09, 2008 6:55 pm

Yep good for you on the rear but the front, its still a problem isnt it?

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

I took a look at the front. The measurements are a bit tougher to determine since the geometry is not quite linear as the rear. If the lift were all due to an OTT spacer, I would definately say yes - an extended stop would be mandatory. The OTT portion on the Revtek, however, is only 3/8" while the bulk of the lift (1-1/4"+) is from the internal spacer. The measurement from the front bumpstop to the top of the a-arm is just at 3". Clearance from the tire to fender is, again, not an issue. I have 4-1/2" from the tire to the fender at closest point.

Since the internal spacer is not as large as the Daystar, I do not believe spring bind (stacking) is an issue either. From approximate eyeballing / measuring there appears to be more than enough room in the spring to exceed 3" of compression. I measured just about an inch of space between the coils in the spring. Depending on where you measure - there are at least 4 "spaces" along the spring. In order for the spring to completely stack - there would have to be close to 4" of compression. Again - Revtek told me definitively that an extended stop was not needed for the front, however I am slightly more leary of that (despite them being correct for the rear).

I used a ramp to articulate the front when I first put the lift on to see if there was any bind or contact on the a-arm. I did not see any but to be safe I DO plan on using extended bump stops for the front. Trying to find one to replace the OEM is the difficult part. I know I could probably fab something to work, but would rather just get one off the shelf. The stop would have to be in the 1"-1-1/2" range. I have seen much larger ones - but I believe those would be too long.

I plan on articulating it again and taking more measurements in the coming week and will post them as well. Suffice it to say that (in my opinion only) based on what I am seeing, a KK with the Revtek driven on roads and only occasional MILD off-road would not need an extended front bumpstop for fender clearance or spring stacking. As for over-compressing the front strut - that is difficult to tell since I cannot easily compress the strut. I think it likely makes sense to assume, however, that the strut should at least allow for maximum spring stack without blowing out - although again, I am assuming this.

Having said that, with the 3" of space currently, it makes sense to put in an extended one just to be safe (assuming its not 2-1/2" to 3" longer!) - especially if the vehicle sees substantial off-road.

HIKJ · **Posted:** Tue Mar 11, 2008 6:11 am

A bumpstop of an additional 3/4" to 1" would seem enough to protect the strut in the front.
I have considered as most simple solution to attach a block of hard rubber on top of the upper A-arm. The material of a rubber mallet, or the famous hockey puck could be used and sawed in the proper form and thickness. What do you think?

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ wrote:

A bumpstop of an additional 3/4" to 1" would seem enough to protect the strut in the front.
I have considered as most simple solution to attach a block of hard rubber on top of the upper A-arm. The material of a rubber mallet, or the famous hockey puck could be used and sawed in the proper form and thickness. What do you think?

Actually I was thinking the same thing. I am going to see if I can cut / modify a puck for that.

HIKJ · **Posted:** Tue Mar 11, 2008 12:13 pm

joshuasjeep wrote:

HIKJ wrote:

A bumpstop of an additional 3/4" to 1" would seem enough to protect the strut in the front.
I have considered as most simple solution to attach a block of hard rubber on top of the upper A-arm. The material of a rubber mallet, or the famous hockey puck could be used and sawed in the proper form and thickness. What do you think?

Actually I was thinking the same thing. I am going to see if I can cut / modify a puck for that.

Please keep me posted how you succeed. How to fix them: glue? straps?
I am planning to do the same mods when I exchange my KJ for a KK (will be marketed here in the next few months).

By the way, if you get a chance, I am interested to know the fully extended length of the rear shocks (center of eye to center of eye). Because this would tell me if I can transplant the OME shocks from my KJ to my future KK.

HIKJ · **Posted:** Tue Mar 11, 2008 12:13 pm

joshuasjeep wrote:

HIKJ wrote:

A bumpstop of an additional 3/4" to 1" would seem enough to protect the strut in the front.
I have considered as most simple solution to attach a block of hard rubber on top of the upper A-arm. The material of a rubber mallet, or the famous hockey puck could be used and sawed in the proper form and thickness. What do you think?

Actually I was thinking the same thing. I am going to see if I can cut / modify a puck for that.

Please keep me posted how you succeed. How to fix them: glue? straps?
I am planning to do the same mods when I exchange my KJ for a KK (will be marketed here in the next few months).

By the way, if you get a chance, I am interested to know the fully extended length of the rear shocks (center of eye to center of eye). Because this would tell me if I can transplant the OME shocks from my KJ to my future KK.

tjkj2002 · **Posted:** Tue Mar 11, 2008 12:35 pm

HIKJ wrote:

joshuasjeep wrote:

HIKJ wrote:

A bumpstop of an additional 3/4" to 1" would seem enough to protect the strut in the front.
I have considered as most simple solution to attach a block of hard rubber on top of the upper A-arm. The material of a rubber mallet, or the famous hockey puck could be used and sawed in the proper form and thickness. What do you think?

Actually I was thinking the same thing. I am going to see if I can cut / modify a puck for that.

Please keep me posted how you succeed. How to fix them: glue? straps?
I am planning to do the same mods when I exchange my KJ for a KK (will be marketed here in the next few months).

By the way, if you get a chance, I am interested to know the fully extended length of the rear shocks (center of eye to center of eye). Because this would tell me if I can transplant the OME shocks from my KJ to my future KK.

If the front bumpstop mounting area is the same as a KJ you could use a longer bumpstop for a KJ.SkyJacker and TerraFlex both make extended front bumpstops for the KJ.Might be worth a shot there.

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ - I measured just a hair over 24-1/2 inches extended on the shock before I installed it.

tkjk2002 - I will take a closer look at the bumpstops on my KK versus my wifes KJ. The mounts do look similar.

HIKJ · **Posted:** Tue Mar 11, 2008 3:34 pm

joshuasjeep wrote:

HIKJ - I measured just a hair over 24-1/2 inches extended on the shock before I installed it.

tkjk2002 - I will take a closer look at the bumpstops on my KK versus my wifes KJ. The mounts do look similar.

Thanks; the shocks are not exchangeable. KK: 24,5" = 622 mm, versus KJ: 559 mm.

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ wrote:

joshuasjeep wrote:

HIKJ - I measured just a hair over 24-1/2 inches extended on the shock before I installed it.

tkjk2002 - I will take a closer look at the bumpstops on my KK versus my wifes KJ. The mounts do look similar.

Thanks; the shocks are not exchangeable. KK: 24,5" = 622 mm, versus KJ: 559 mm.

I was thinking - the measurements I gave you were for the Rancho RSX shocks. Is that what you were wanting or were you wanting the length of the OEM shocks??

HIKJ · **Posted:** Wed Mar 12, 2008 6:38 am

joshuasjeep wrote:

HIKJ wrote:

joshuasjeep wrote:

HIKJ - I measured just a hair over 24-1/2 inches extended on the shock before I installed it.

tkjk2002 - I will take a closer look at the bumpstops on my KK versus my wifes KJ. The mounts do look similar.

Thanks; the shocks are not exchangeable. KK: 24,5" = 622 mm, versus KJ: 559 mm.

I was thinking - the measurements I gave you were for the Rancho RSX shocks. Is that what you were wanting or were you wanting the length of the OEM shocks??

Yeah, I was looking for the length of the oem shocks.
If the longer Rancho's are 622 mm, the oem's might well be the same as the original KJ's . Hope you'll get a chance to find out.

Another side issue: with the long Rancho's and only 1.25" of lift, will the coils stay in place at full extension, or do they come loose?

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ wrote:

Yeah, I was looking for the length of the oem shocks.
If the longer Rancho's are 622 mm, the oem's might well be the same as the original KJ's . Hope you'll get a chance to find out.

Another side issue: with the long Rancho's and only 1.25" of lift, will the coils stay in place at full extension, or do they come loose?

I will get the measurement of the OEM shocks as soon as I get home tonight.

As for the coil springs staying in place, I dont think it would be a problem but I have not drooped the suspension to test it. I know in order to get the springs in place I had to drop the axle a substantial amount (including disconnecting the lowers shock bolt and sway bar links).

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ - I measured the OEM shocks. At extension it is just over 21-3/4" in length eye to eye.

HIKJ · **Posted:** Thu Mar 13, 2008 9:19 am

joshuasjeep wrote:

HIKJ - I measured the OEM shocks. At extension it is just over 21-3/4" in length eye to eye.

Ah well, that's equal to the KJ's (give or take a few mm's).

Now I am getting also interested if the Old Man Emu front struts of my KJ could be used on the KK. The critical measurements would be:
1) bolt pattern of the four bolts at the top
2) diameter of the bottom part of the strut around which the clevis is clamped
3) maximum extended lenght from top of the upper bracket (with the 4 bolts) to the top of the clevis fork.
I know it is a tall order, but I would be very grateful if you could find out.

Diggerfreek · **Posted:** Thu Mar 13, 2008 9:29 pm

the clevis it self is an inch longer...

joshuasjeep · **Joined:** Thu Feb 21, 2008 5:27 pm **Posts:** 22

HIKJ wrote:

joshuasjeep wrote:

HIKJ - I measured the OEM shocks. At extension it is just over 21-3/4" in length eye to eye.

Ah well, that's equal to the KJ's (give or take a few mm's).

Now I am getting also interested if the Old Man Emu front struts of my KJ could be used on the KK. The critical measurements would be:
1) bolt pattern of the four bolts at the top
2) diameter of the bottom part of the strut around which the clevis is clamped
3) maximum extended lenght from top of the upper bracket (with the 4 bolts) to the top of the clevis fork.
I know it is a tall order, but I would be very grateful if you could find out.

Some of those measurements are going to be pretty tough to get without removing the strut. I will compare the top bolts between my KK and my wifes KJ and try to get some other measurements this weekend.

HIKJ · **Posted:** Fri Mar 14, 2008 1:48 pm

Diggerfreek wrote:

the clevis it self is an inch longer...

Okay, but that is "harmless"

Just FYI on Revtek lift - dont need rear extended bumpstops

Who is online