4bangerjp.com
General Forums => The Mess Hall => Topic started by: neale_rs on May 15, 2008, 11:29:21 AM
-
My front wheel droop stops with 2" of shock travel remaining. I already loosened the spring clamps but it did not help much. How does this sound:
Currently the tire up travel is limited by the tire hitting the fender (metal part). I think that if it were limited by a bumpstop, the tire moving up would be able to apply leverage to lower the opposite tire a bit more. This, if it works, would force a bit more droop. It would be great if limiting the up travel by say 1" would get me 2" of additional droop on the opposite side of the axle. The first inch would get me to the current articulation and the second inch would be additional articulation not available to me now.
Do you think this would work?
Thanks
-
There are several things that come into play then looking at the suspention travel. Having a bumpstop on the other side would help put leverage on the drop side. How much, is uncertain. Also you might want to see if the shock location is an issue. Disconnect the shock and see if that helps any.
-
I disconnected the shock to verify that is had those extra 2 inches. For now, I'll try simulating a bump stop with blocks of wood to see if it helps before making anything made of metal. Also, basic physics would suggest that the more inboard the bump stop, the more leverage would be exerted to make the opposite side droop. Have you ever hear of this being done?
Thanks
-
I disconnected the shock to verify that is had those extra 2 inches. For now, I'll try simulating a bump stop with blocks of wood to see if it helps before making anything made of metal. Also, basic physics would suggest that the more inboard the bump stop, the more leverage would be exerted to make the opposite side droop. Have you ever hear of this being done?
Thanks
It should work, but I'm not sure if you'll get the 2". You could experiment and put something 2" thick and see what happens. What's also not helping is that the leaf spring is rotating as it's dropping. If you have poly mounts these tend to be stiffer then rubber mounts and could account for a little of it. Things like Revolver shackles are hated but they do relieve the torsion on the leaf spring. All those little things add up when you're trying to get those last few inches of fine tuning.
-
Why do you want to force more droop? Unless there is weight on the tire so you get some traction any additional droop is only good for impressing people at an RTI Ramp.
-
Your leverage theory will work to a point, and may be limited by how much twist the springs and shackle bushings will allow.
-
Why do you want to force more droop? Unless there is weight on the tire so you get some traction any additional droop is only good for impressing people at an RTI Ramp.
It just bothers me to be wasting 2" of shock travel. There must be some way to be able to use it.
-
It may be better to save up for some lockers and just let the tires come off the ground!
Thanks to all for your comments. It seems there is no really easy way to get the extra droop.
-
You will also only droop until the drooped spring is parallel with the shackle, as the length of the spring and shackle combined will not get any longer.
-
My springs don't get to that point yet. Maybe it is better so that the shackles don't invert.
-
I would say that what is limiting your droop is the length of the shackle relative to the length of the spring. Compression sound like you are almost getting to a flat spring before the tire is stopped. The shackle will swing depending on the length needed by the spring. This is what makes your spring compress and expand. I would first loosen the shackle and leaf eyes bolts. You don't want to 'squish' the bushings in the shackle or the spring eyes. Next take a string. Tie a knot where the spring eye is, follow the length of the top spring and tie another knot where the leaf eye is. Follow the string to the other shackle eye and tie another knot. When the spring functions through the suspension cycle, it will flatten from a convex shape. If you had light weight capacity springs, it may even go to concave (ie GM leaf sprung front).
Have you also disconnected the track bars (panhard) from the axles. This actually pulls the leafs into the bushing and the mount.
-
You are correct in that the spring goes nearly flat when the tire hits the fender. The sway bars and track bars are off when off road. Also, the shackles are 5 inches long, 1 inch longer than stock.
I´ll check the torque on the shackles to see if that helps although they do swing up and out pretty well on compresion.
Could you explain what the string is for? Didn't quite get it.
Thanks.
-
The string is the representation of the leaf actual length and the shackle actual length. With the string, you can pull it taunt to represent the flat spring and with the knots to represent the eyes where the shackle and spring pivot off. This will tell you if your shackle is too short for the leaf to flatten and even to go concave during its cycle.
-
The idea of "forced droop" is addressed by running a quarter elliptical suspension set up. With your set up, there would be no way to force the suspension to articulate. You cannot force the matter by changing the fulcrum. You are trying to exert more pressure on a smaller lever to move a longer lever. The effects will be minimal at best...
-
The string is the representation of the leaf actual length and the shackle actual length. With the string, you can pull it taunt to represent the flat spring and with the knots to represent the eyes where the shackle and spring pivot off. This will tell you if your shackle is too short for the leaf to flatten and even to go concave during its cycle.
Thanks, that makes sense.
-
The idea of "forced droop" is addressed by running a quarter elliptical suspension set up. With your set up, there would be no way to force the suspension to articulate. You cannot force the matter by changing the fulcrum. You are trying to exert more pressure on a smaller lever to move a longer lever. The effects will be minimal at best...
A quarter elliptical suspension set up would articulate more, thats for sure. I still think the regular type spring could arch down a bit more. After all, the tire going up has weight on it and the one going down usually has very little weight on it so yeah short lever moving a long lever but with a lot of force on the short side and almost none on the long side. Heavier tires, wheels and axle should also help.
Thanks
-
(http://i7.photobucket.com/albums/y258/fourcyljeep/albumtn.jpg)
Here is my jeep... It flexes fairly well for spring under. It works perfect for my style of driving. The biggest difference outside of spring rates are the addition of boomerang shackles.
-
Your flex does look good. I also have boomerang shackles in the rear, regular ones in the front, all are 5" long, one inch longer than stock.
This is pretty much the full extent of my YJ's droop (with 33s). The upward travel is currently limited by sheet metal.
Rear:
(http://i138.photobucket.com/albums/q277/neale_rs/trips/Mina%20Hidalgo/DSC07390.jpg)
Front:
(http://i138.photobucket.com/albums/q277/neale_rs/trips/Mina%20Hidalgo/Mina20520Mayo20200820060_1.jpg)
It isn't too bad but I have seen some SUA jeeps droop a bit more. This one with 34s is one example, and this is with the sway bar connected!
(http://i138.photobucket.com/albums/q277/neale_rs/trips/Mina%20Hidalgo/Mina20520Mayo20200820089.jpg)
-
I had to cut the fenders because I was getting into them. They looked like dog pooh after a few trees (glad I am not in Texas anymore). I went with the BDS 3.5 lift springs and the 5/8 inch boomerangs from M.O.R.E. That is a 35 in my pic...
That CJ has some mad flex to it for being SUA!
Are you keeping your shackles greased? Are they "over torqued"? Check the spring hanger too. Have your springs had a chance to break in? ie, have you lifted the jeep recently? Springs need some break in time. The track bar could be limiting your down travel. Have you installed a longer or adjustable track bar? Not to hash this over too much, I ditched mine. That is not a recommendation so much as a statement of what action I took. That was the only major difference that stood out to me in pics you posted. CJ's didn't have them, YJ's did.
-
I just saw your sig... No track bars... Scratch that idea.
-
I'll give it some time to break in, as you recommend. The lift has been on for 3 months and has been wheeling 5 times but only 2 of those have been demanding enough to make it flex significantly. Maybe a few more trips will do the trick, that and making sure there is no over torque.
Thanks
-
what is the correct amount to torque down your shekels???? i ask because i thought i had mine pretty tight and then i looked earlier this week and i was missing a nut and the bolt was about to give way :yikes:... since its time to put on the new shakels i fugue i mis as well get it all right now..
-
what is the correct amount to torque down your shekels???? i ask because i thought i had mine pretty tight and then i looked earlier this week and i was missing a nut and the bolt was about to give way :yikes:... since its time to put on the new shakels i fugue i mis as well get it all right now..
I think the manual says 95lbs-ft but if you use self-locking nuts you can drop it down to say 40lbs-ft. I know some people tighten them till the bushing is just compressed. It's really a try and test sort of thing.
-
ok, thanks... ill probably get some self locking nuts and change the shekels this weekend. and hopefully by then i can get those :rant: rusty nuts off my sway bar to get the disconnects on....
-
It's good practice to check all suspension bolts just before each wheeling trip (maybe after too although I'm too lazy to do this), this will allow you to run low torque with no problems. Also the u-joint bolts, I´m convinced a lot of u-joint failures happen because people head out on the trail with those bolts already a bit loose.
-
Finally got around to checking the spring bolt torques. They were all at about 70 - 75. I loosened them and retorqued the main eye bolts (4 of them) to 70 and the shackle bolts (all 8) to 55. I'm hoping to get out on the trail next weekend for testing. On road it feels like it has softened up, maybe a bit more bump steer, so it seems like it does have some effect. Do my torque values sound OK?
Thanks
-
I agree. It bothers me that some mechanics don't take proper torque seriously enough. I currently own 4 torque wrenches, including a big one that goes up to 250.