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question about bump stops and there effects on flex...

so one thing i either skimmed over or it wasn't posted is what limiting up travel does. if you don't have enough up travel it makes the rig much more unstable in off camber situations.

balance is key. you need to have a suspension system that can articulate to the terrain you wheel in.

wheeling is all about driving over harder terrain. in all the wheeling i've done i don't ever remember seeing any sign anywhere saying you need a certain rti score to go down the trail.
 
Limiting uptravel keeps you from bottoming your shocks (very bad) or stuffing a tire into the bodywork (not so bad depending on how much you care about dents).Or, if you have binding at any point during uptravel, or if the steering contacts anything it shouldn't, you can bumpstop it before hitting either point.
 
Darky said:
I have so much flex that my coils will come unseated by almost 4 inches. 4 inches of that flex is useless. When I get the time and money, I plan on buying limit straps and lowering my lower shock mounts in order to limit my droop.
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and that makes it overrated how? first of all, yes having no weight on the axle makes it almost useless, however its still not as useless as it just dangling. flex is related to stability in that without flex, you sure arent going to have any stability. extra flex isnt going to make you less stable either. using the bumpstop to pivot the axle will work, but it will also force the body to pivot a little. If you dont have the travel to actually take advantage of the axle pivot, all youre going to get from it is body pivot, AKA more off camber, AKA rollover

I dont disagree with bumpstopping, youre going to stop the axle one way or another, best to do it in a way thats not going to ruin your equipment, but IMO anything more than what the minimum is is just an excuse to not have cut/hammered/etc where you should have.
 
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Hoooper said:
and that makes it overrated how? first of all, yes having no weight on the axle makes it almost useless, however its still not as useless as it just dangling. flex is related to stability in that without flex, you sure arent going to have any stability. extra flex isnt going to make you less stable either. using the bumpstop to pivot the axle will work, but it will also force the body to pivot a little. If you dont have the travel to actually take advantage of the axle pivot, all youre going to get from it is body pivot, AKA more off camber, AKA rollover

I dont disagree with bumpstopping, youre going to stop the axle one way or another, best to do it in a way thats not going to ruin your equipment, but IMO anything more than what the minimum is is just an excuse to not have cut/hammered/etc where you should have.
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Who has said to bumpstop more than necessary? A tire with no pressure to hold it down will not help you in any way. I've seen people stuck with all four tires on the ground, but with open diffs were just spinning one tire on each axle because they were flexed out so far that while they were in contact with the ground, there was nothing to push the tires down. The point is to balance the pursuit of flex with the pursuit of traction.

Bumpstop to protect the shocks and body; limit strap to keep the axle from drooping far enough to hit the end of the shocks travel or from unseating your coil. Flex is overrated in that people like you will automatically turn defensive if anyone tries to point out that flex is only part of the equation. You don't read the rest, you just defend flex. Flex is good, yes, but just because you have a RTI score of 1000 doesn't mean you will automatically perform better than someone who "only" scored a 600.
 
techno1154 said:
Correct me if I am wrong but bump stopping limits up travel but do nothing to increase down travel.
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bumpstopping allows you to do things to increase down travel. and you can gain more down than you sacrificed up

XJLI said:
Penrose256.jpg
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i heard that if you lift a tire, bunnies die
 
Hoooper said:
bump stops arent going to increase your down travel. no matter how much bump stop you put on, you will still have shocks, brake lines, bind to limit the down travel
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not sure I follow much, if any, of what you've said so far, but this last post has me confused.

"bumpstops aren't going to increase travel"
why not? just because they limit up travel doesn't mean they limit droop. in fact as stated the bumpstop can act as a pivot. with enough pressure pushing a stuffed tire up, that energy is transferred downwards on the opposite side tire. so stuffing one tire into it's bumpstop, would result in added down travel to the other.

"no matter how much bump stop you put on, you will still have shocks, brake lines, bind to limit the down travel"
well if setup properly none of those should be limiting downtravel, that's what limit straps are for.

I would agree with those who say that a ballanced suspension will/does out perform a super flexible suspension. as sad as it is to say, look at a Humvee, it don't flex worth shit, but for the most part it will keep moving because the tires that are touching the ground have weight on them.
and as Darky mentioned, it seems your arguing for the sake of arguing, thinking something doesn't make it fact/true. keep an open mind to what some people are saying, they aren't doing it for the e-cred.
 
This thread remind me, I need some Hockey Pucks and 1x1 square tubing......
 
Darky said:
Who has said to bumpstop more than necessary? A tire with no pressure to hold it down will not help you in any way. I've seen people stuck with all four tires on the ground, but with open diffs were just spinning one tire on each axle because they were flexed out so far that while they were in contact with the ground, there was nothing to push the tires down. The point is to balance the pursuit of flex with the pursuit of traction.
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a tire with just 1 lug on the ground has more traction that a tire with 0. you can grip the edge of a rock, a chunk or mud, anything that a tire not on the ground cannot do. why are you talking about open diffs anyway? if those guys that had no traction had a little less flex would their open diff all of a sudden become locked? Im just not getting how you are imagining that having more flex is going to get you less traction. Never seen it happen, nor have i ever seen an open diff dangling a tire have traction but one with a toe in the dirt be worthless

Darky said:
Flex is overrated in that people like you will automatically turn defensive if anyone tries to point out that flex is only part of the equation. You don't read the rest, you just defend flex.
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you obviously dont know anything about me, but thanks for playing. im here trying to get to the bottom of your words which seem to not make sense even to themselves

beakie said:
not sure I follow much, if any, of what you've said so far, but this last post has me confused.

"bumpstops aren't going to increase travel"
why not? just because they limit up travel doesn't mean they limit droop. in fact as stated the bumpstop can act as a pivot. with enough pressure pushing a stuffed tire up, that energy is transferred downwards on the opposite side tire. so stuffing one tire into it's bumpstop, would result in added down travel to the other.

"no matter how much bump stop you put on, you will still have shocks, brake lines, bind to limit the down travel"
well if setup properly none of those should be limiting downtravel, that's what limit straps are for.
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no matter what you do to bumpstop, its not going to extend your limit straps, shocks, or brake lines. its very simple. Most suspensions are limited by one of those three, "proper" or extra bumpstopoing is not going to add length to any of those three items.
 
Hoooper said:
a tire with just 1 lug on the ground has more traction that a tire with 0. you can grip the edge of a rock, a chunk or mud, anything that a tire not on the ground cannot do. why are you talking about open diffs anyway? if those guys that had no traction had a little less flex would their open diff all of a sudden become locked?


Im just not getting how you are imagining that having more flex is going to get you less traction.
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i doubt that 1 lug with nearly no weight on it will be difference between making it over or through an obstacle or not. if i have a limit strap that limits droop to the point where the coil has just become unseated i will not be denied anything more than someone that limits their suspension at a point where the coil is drooped multiple inches and not forcing the axle down anymore. you need weight to have traction.

hes not saying more flex = less traction. he is saying that more flex does not necessarily equate to more traction. there is a difference.
 
Hoooper said:
you obviously dont know anything about me, but thanks for playing. im here trying to get to the bottom of your words which seem to not make sense even to themselves
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You obviously don't know as much as you think you know. Darky knows what he is talking about, you have yet to prove to me that you do. I am still tweaking my bumpstops for the current suspension setup and many things posted in this thread have shed some new light for me.
 
your suspension should only droop until your shocks are fully extended and your springs are still seated.

this thread is full of misinformation and failure... if you really want to know how your suspension reacts then take your springs and shocks off and cycle it. I guarantee you will be really surprised with the way it reacts.

and just to stir the pot, anyone running the factory style suspension on their XJ will not get 10" of travel on the passenger side, but will get about 11" on the driver side.

bumpstops are not "levers" to give you more downtravel, they are to stop your axle from destroying things.

having enough droop to unseat your springs is pointless and can lead to your vehicle being extremely unstable.

the best way to run is to strap to the full extension of your shocks and bumpstop to the point that your shocks are fully compressed and or you are not damaging anything else (whichever comes first)
 
Hoooper said:
no matter what you do to bumpstop, its not going to extend your limit straps, shocks, or brake lines. its very simple. Most suspensions are limited by one of those three, "proper" or extra bumpstopoing is not going to add length to any of those three items.
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so your saying a suspension is limited by either shocks, brakes lines or straps? really? if your limited by shocks/lines, get longer shocks/lines, otherwise I would use straps to limit my travel to less than what my shocks/lines would allow. thus less flex then is possible, however still a better set up then "max flex is best". and obviously it won't add travel, but it can cause that tire hanging in the air downwards, allowing it to reach it's full droop potential.

I'm sure everything you say is making sense in your head, but it's not adding up in others.

so your trying to argue that a super max flexing rig is better then one that has proper limit straps/bumpstops, which keep it stable, ballanced and in control? am I getting that right?

if that's the case why do some rock racing buggies only use 12-16" of travel when there are shocks/systems out there providing much more then that?
and why don't people build long arms 48" long on an XJ? I mean you could fit them, and they would flex like crazy, but you will find plenty of mid-arm 3-link builds that will out perform your "max flex" theory.
 
89eliminator said:
i dont agree with this statement. i can unseat my coil about 4" and my rig is FAR from unstable.
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Think about it this way if your coil is unseated your jeep is now only being supported by 3 wheels. More stable? Think again
 
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