suspension up-travel

[Chuckman]

What are you guys running for suspension uptravel on your front suspension- not buggies, but streetable rigs... I am talking about hitting a speed-bump with equal L&R compression, not ramping. I get a lot of droop that supports nice ramp numbers, but dont know how to figure true street compression. I have been looking at stock TJ's here in the lot at work and they are only like 3" before the shocks bottom out. I want to lower as much as I can for CG but dont want to rob that uptravel for the baja runs on the main roads at Callalante for instance. This is a coiled CJ btw.
oh, and one for the homies

 

[Rich]

I wouldn't go any less than 4" up if possible.

 

[paradisePWoffrd]

you gotta think though, that because of the distance from the pivot point, if the shock has 3" of uptravel, the wheel/tire will have more then that.....

so the question is are you wanting to know wheel travel, or suspension travel?

also if you are wanting it to have enough travel to handle speedbump size objects, then you can say that youd want your tire to be able to have ~8-12" uptravel.... and then depending on how wide the axle is and how far the suspension is from the WMS you can figure out your required suspension uptravel

 

[spraypaintman]

What are you guys running for suspension uptravel on your front suspension- not buggies, but streetable rigs... I am talking about hitting a speed-bump with equal L&R compression, not ramping

I have about 7" of up travel on my cj7.

paradisePWoffrd - He's asking about suspention uptravel. Says so right there in his post.

 

[SSWaters]

George always told me a fist or 2 between your tire and sheetmetal/frame/etc was good enough.

 

[leach]

you gotta think though, that because of the distance from the pivot point, if the shock has 3" of uptravel, the wheel/tire will have more then that.....
so the question is are you wanting to know wheel travel, or suspension travel?
also if you are wanting it to have enough travel to handle speedbump size objects, then you can say that youd want your tire to be able to have ~8-12" uptravel.... and then depending on how wide the axle is and how far the suspension is from the WMS you can figure out your required suspension uptravel

I am lost on your logic here with relation to a speed bump/go fast scenario. If both tires hit a speed bump, they will be traveling the same vertical distance as everything attached to the axle. There is no flex in this situation. So 3" of uptravel of the AXLE=3" on the shock=3" on the tire.

Say if you do the opposite of a speed bump and say suck down the front suspension with a winch. The springs will compress say 4" for example. The shocks will also compress 4 inches and the tire will get 4" closer to the body.

Worrying about if the tire is going to hit the body at flex or not is a matter of correctly setting up bumpstops. You can make a rig have 1" of uptravel or 10". The tire will hit the same spot no matter what at full compression in either scenario on the same obstacle.

So my answer is build the suspension to clear everything upon full droop and full stuff steering lock to lock. Then when you mount your suspension you decide on the amount of uptravel, spring rates, etc. at that time. A stiffer spring and more uptravel is no excuse for a poorly thought out or executed suspension. Goodluck in the project.

 

[Chuckman]

The issue here guys is the hogshead of the front D60 in this application is perilously close to the passenger frame rail. In an effort to keep a low CG, I want to keep lift low, but this eats my uptravel. I was wanting to know how much people have and how much they have seen used. I used to run a spring under lift with about 6" of allowable uptravel but never saw more than about 4" of mud rubbed off the shocks after a weekend- telling me in that situation, I didnt need massive amounts of uptravel. However, I dont want to limit anything or beat the wee out of the jeep when playing around. In the case of the fender rub- these tires tuck nicely into the fenders at good axle twist that would normally rub at parallel compression. In any case, I only have about 3.75" inches of compression before the diff hits the frame so I think I will put in about 1.25" more and see if thats enough.

 

[leach]

4" is a good number to start with. It is what I will be running on my two buggies to start out with. I say starting point because with a link suspension you have many factors that will change how much uptravel you will need to not hit bumps going slow, fast, etc. Build it, run it, change it as needed. Goodluck

 

[drkelly]

4-4.5" between axle and bumpstops on my front axle. I found out the hard way at DPG 1.5 wks ago that my bump stops compress farther than I anticipated.

 

[Tacoma747]

Mine is 6-7 or so on each side, but it never fully compresses unless it is REALLY flexed. Regular driving (well, you know...) I normally don't use but about 4" of uptravel.

I don't like bottoming out shocks, and with the setup I have they don't bottom unless it is REALLY flexed (think I have bottomed one of the shocks 1-2 times, I raise the little rubber o-rings up before wheeling to see how compressed they get).

My frame height is about 27" on 39's. I wanted lower, but there is NO room for the D60 in the front to be any higher (or truck to be any lower ), it is a very tight fit as is...

 

[Rich]

Mine is 6-7 or so on each side, but it never fully compresses unless it is REALLY flexed. Regular driving (well, you know...) I normally don't use but about 4" of uptravel.

My frame height is about 27" on 39's. I wanted lower, but there is NO room for the D60 in the front to be any higher (or truck to be any lower ), it is a very tight fit as is...

These 2 statements seem (to me) very contradictory.. Why not lower it 2", you'd have 4-5" uptravel, and be down to 25"?