Are new bumpstops necessary with Rusty's 2.5" lift?

BeepBeepJeepJeep · **Posted:** Tue Jun 26, 2007 5:00 pm

If I do not put new bumpstops on and the tires get stuffed, will I do any damage? Tires will be 245/75/16.

Edit: I would like to order the bump stops then. What brand and where should I order from? Also, would two additional rear spring isolators on each side in the back supplement new bumpstops?

Edit2: Are these what I want?

http://www.rjroffroad.com/Daystar-EVS-Foam-Bump-Stops-pr-16912.html

Also, what is the difference between a soft bump stop and a hard bump stop? I thought they were only there to prevent over-travel.

jason thompson · **Posted:** Tue Jun 26, 2007 7:02 pm

BeepBeepJeepJeep wrote:

If I do not put new bumpstops on and the tires get stuffed, will I do any damage? Tires will be 245/75/16.

stock rims with NO spacers you will be fine
at least I have very minor rubbing at full tire hanging stuff out back
it will make a clean spot on the liner in 2 places at the top and on the inside wall and it will rub the paint off of the front most part of the flair
but they are plastic so it dont need paint

in the front I can not get it to stuff that far that I can see
I know that even with a front tire off the ground I can still see piston rod on the strut

Jeepjeepster · **Posted:** Tue Jun 26, 2007 7:09 pm

You may have alittle rubbing on the rear..

jason thompson · **Posted:** Tue Jun 26, 2007 7:46 pm

Jeepjeepster wrote:

You may have alittle rubbing on the rear..

read above :mrgreen:

myjeepwalks · **Posted:** Tue Jun 26, 2007 8:42 pm

I haven't ripped anything off yet.

BeepBeepJeepJeep · **Posted:** Tue Jun 26, 2007 8:58 pm

I would like to get bump stops then... where should I order them from and what brand? Also, would two additional rear spring isolators on each side in the back supplement new bumpstops?

Thanks!

jason thompson · **Posted:** Tue Jun 26, 2007 9:24 pm

BeepBeepJeepJeep wrote:

I would like to get bump stops then... where should I order them from and what brand? Also, would two additional rear spring isolators on each side in the back supplement new bumpstops?

Thanks!

Nope the new isolators will give you more lift but will not limit your up travle
bump stops keep the axel from going to far up

as far as what to use any thing that is metal or rubber/poly that will keep the axel from going up to far
for 245/74 on an OE wheel with no wheel spacers you may need 3/4-1"
I am using some from a F250/350 lift and cutting them down to 1"
they are made strong ,3/4 ton trucks are heavy, and have a steel back with a bolt on it I will let you know in 6 months when I get around to doing it

SoDakJeep · **Posted:** Tue Jun 26, 2007 9:53 pm

use rubber hockey pucks....theres a write up somewhere but im not sure it was on a kj.

BeepBeepJeepJeep · **Posted:** Tue Jun 26, 2007 10:48 pm

Are these what I want?

http://www.rjroffroad.com/Daystar-EVS-Foam-Bump-Stops-pr-16912.html

Also, what is the difference between a soft bump stop and a hard bump stop? I thought they were only there to prevent over-travel.

Rock Lizard · **Posted:** Tue Jun 26, 2007 11:11 pm

Bumpstops are necessary on a properly tuned suspension. They not only keep your tires from hitting where they shouldn't, but they also control flex so you don't over compress your expensive lift springs causing premature wear and sag.

Here is a tech article I did (not on a KJ, but same principles apply) on adjusting bumpstops, and it mentions using hockey pucks, which are nice because they are dirt cheap ($1 in most places), they are hard rubber, so almost no compression but easy to drill holes for mounting bolts, they are exactly 1" in thickness, and the diameter is enough for using in the rear coil buckets on a KJ.
http://www.rocklizardfabrications.com/A ... pstops.htm

I also sell 2" HDPE bumpstops that I manufacturer myself that are 2" in height and come with instuctions and hardware (scroll down a little to find them):
http://www.rocklizardfabrications.com/g ... sories.htm

You don't want soft bumpstops. Those I would think are mostly for prerunner type suspension setups with a lot of jumping and landing.

RQuarte · **Posted:** Tue Jun 26, 2007 11:27 pm

Im running 245/75-16 MT/R's without new bump stops in the back and it get some rub sometimes, do it right the first time and throw the new bump stops in, saves the headache later.

BeepBeepJeepJeep · **Posted:** Wed Jun 27, 2007 9:58 am

Rock Lizard wrote:

Bumpstops are necessary on a properly tuned suspension. They not only keep your tires from hitting where they shouldn't, but they also control flex so you don't over compress your expensive lift springs causing premature wear and sag.

Here is a tech article I did (not on a KJ, but same principles apply) on adjusting bumpstops, and it mentions using hockey pucks, which are nice because they are dirt cheap ($1 in most places), they are hard rubber, so almost no compression but easy to drill holes for mounting bolts, they are exactly 1" in thickness, and the diameter is enough for using in the rear coil buckets on a KJ.
http://www.rocklizardfabrications.com/A ... pstops.htm

I also sell 2" HDPE bumpstops that I manufacturer myself that are 2" in height and come with instuctions and hardware (scroll down a little to find them):
http://www.rocklizardfabrications.com/g ... sories.htm

You don't want soft bumpstops. Those I would think are mostly for prerunner type suspension setups with a lot of jumping and landing.

Wow that is creative as hell. How many hockey pucks would I need to use on each side?

Edit: Nevermind, I re-read your writeup.... So if I'm doing a 2.5" Lift + .5" Rear spring isolater = 3" I will need 3 pucks on each side?

Rock Lizard · **Posted:** Wed Jun 27, 2007 12:16 pm

BeepBeepJeepJeep wrote:

Wow that is creative as hell. How many hockey pucks would I need to use on each side?

Edit: Nevermind, I re-read your writeup.... So if I'm doing a 2.5" Lift + .5" Rear spring isolater = 3" I will need 3 pucks on each side?

Best way to know for sure is to flex it to the point you want it to stop, then measure the distance between the existing bumpstop and the contact point. Take that measurement, add about 1/2" for rubber compression on the stock bumpstop, and there you go.

USPLibby · **Joined:** Thu Jul 28, 2005 12:29 am **Posts:** 377

I have 265x70 16 sized tires and I don't get that much rubbing, just a little on the left inside/top of the wheel well.

I only added one hockey puck, just enough to keep my shocks from bottoming out.

sandracer · **Posted:** Sat Jun 30, 2007 12:03 pm

OK. I've seen the post about the "formula" for determining how much bump stop to use and read Rock Lizard's tech article. The problem is my current health situation doesn't permit me to do the measuring and installation myself. I'm having a local shop put in my lift and would like to get the bumpstops installed at the same time. I'm providing all the parts for them to install.

I'll be running OME coils, front and rear, Rancho struts and shocks, Spydertrax spacers and 245/65/17's on my stock 17 x 7 wheels. Will one inch tall bumpstops do the trick or should I use more?

I know RockLizard has the 2 inch ones available, I believe the Daystars are about 1 inch tall ( judging from the pics of the Frankenlift pieces), and I found a variety of styles and heights on Summit's site.

Bs02KJ · **Posted:** Tue Jul 10, 2007 11:34 pm

I did not put in new bumpstops....I am also about to upgrade to a 265/75/16 tire....I have no rubbing issues and no problems at all with my current tires.
You will be just fine.

BeepBeepJeepJeep · **Posted:** Wed Jul 11, 2007 5:26 am

Bs02KJ wrote:

I did not put in new bumpstops....I am also about to upgrade to a 265/75/16 tire....I have no rubbing issues and no problems at all with my current tires.
You will be just fine.

Do you wheel your jeep at all?

Bs02KJ · **Posted:** Wed Jul 11, 2007 1:11 pm

We do alot of soft sand beach driving and mud running (so yes I do have it in 4 wheel drive quite often)....but I am not in an area where I can do any serious rock crawling....still no issues.
I expect a bit of rubbing with the 265's but nothing that will cause me any serious issues and I have never had any issues at all with the bump stops.
I do know that the 2002 stock Libby is a bit taller than newer models of stock Libbys....so I am not sure how much of that will factor in as well.

tjkj2002 · **Posted:** Wed Jul 11, 2007 4:12 pm

Bs02KJ wrote:

We do alot of soft sand beach driving and mud running (so yes I do have it in 4 wheel drive quite often)....but I am not in an area where I can do any serious rock crawling....still no issues.
I expect a bit of rubbing with the 265's but nothing that will cause me any serious issues and I have never had any issues at all with the bump stops.
I do know that the 2002 stock Libby is a bit taller than newer models of stock Libbys....so I am not sure how much of that will factor in as well.

When you put a coil lift on it does not matter if your KJ is a pre-lowered one or not,actually a pre-lowered KJ will only get 1.75" of lift from a 2.5" coil lift.I have to have rear bumpstops or I'll be ripping more then my rear flares off(which I've done so I removed them),but I do rockcrawling and do stuff my tires often,mud running you'll not see the extreme flex as rockcrawling will so you'll get away from not having rear bumpstops running 265/75's.Now if your running 245/75's then you should not need rear bumpstops because those tires are alot smaller.

Bs02KJ · **Posted:** Wed Jul 11, 2007 10:18 pm

Good info and great looking Jeep! ....

Are new bumpstops necessary with Rusty's 2.5" lift?

Who is online