Uptravel with RK 2.5in X-factor Mid Arm lift
06-10-2014, 06:17 AM
#12
Former Vendor
I've got the new front uppers and lowers, and the front track bar installed to the lengths given in the instructions. I don't have either of the springs on, but I have the passenger side shock on. The passenger side is fully drooped. I jack up the drivers side and the track bar contacts the differential when there is still ~4-6 inches between the stock bump stop pad and the top of the bump stop rubber.
Attachment 558586
I can get a measurement for this distance after work tonight.
Attachment 558587
I thought that the tire would define the clearance, not the trackbar. I called RK, and they said that I need to put the shock on the drivers side and that it would limit the uptravel before the trackbar hits and that I should size my bump stop to prevent that from happening. However, I was expecting to put 2-3" of bump stop on and to prevent this from happening I would need more then 2-3" of bump stops. Communication with RK was further hindered over the phone because I didn't know the extended and compressed lengths of my fox shocks when I called them and they recommend bilstein 5100s. I would have bought those, but they were out of stock so I got the foxshocks for a 1.5 in - 3.5 in lift. I looked up the extended and compressed lengths:
Part number FOX980-24-887 specs are:
Front shocks
Extended 25.15 inch
Compressed 15.55 inch
9.6 inch travel 2-4 inch lift.
The generic recommended shock lengths from RK are:
Generic Front Shock
Recommendation with 2" bump stops - 16" Collapsed to 28" Extended
So since the compressed lengths are both very close to 16" the shock shouldn't matter right? Can someone help me sort this all out? This is the first lift kit I've installed and I want to make sure everything is clearanced properly for offroading.
BTW, my Jeep is a 2010 Wrangler Rubicon 2 door
Thanks,
Nate
Attachment 558586
I can get a measurement for this distance after work tonight.
Attachment 558587
I thought that the tire would define the clearance, not the trackbar. I called RK, and they said that I need to put the shock on the drivers side and that it would limit the uptravel before the trackbar hits and that I should size my bump stop to prevent that from happening. However, I was expecting to put 2-3" of bump stop on and to prevent this from happening I would need more then 2-3" of bump stops. Communication with RK was further hindered over the phone because I didn't know the extended and compressed lengths of my fox shocks when I called them and they recommend bilstein 5100s. I would have bought those, but they were out of stock so I got the foxshocks for a 1.5 in - 3.5 in lift. I looked up the extended and compressed lengths:
Part number FOX980-24-887 specs are:
Front shocks
Extended 25.15 inch
Compressed 15.55 inch
9.6 inch travel 2-4 inch lift.
The generic recommended shock lengths from RK are:
Generic Front Shock
Recommendation with 2" bump stops - 16" Collapsed to 28" Extended
So since the compressed lengths are both very close to 16" the shock shouldn't matter right? Can someone help me sort this all out? This is the first lift kit I've installed and I want to make sure everything is clearanced properly for offroading.
BTW, my Jeep is a 2010 Wrangler Rubicon 2 door
Thanks,
Nate
Sir,
The measurements that you used should be absolutely fine. We install hundreds of these exact kits and those are the starting measurements that we use. Of course them being starting measurements and the fact that every vehicle sits differently you may need to adjust them from that point to get you vehicle dialed in. As you increase shock length the body of the shock is in turn going to be longer. This is inevitably why your new longer shock will bottom out first before your factory bumpstops do. This is also why you need to add more bump stop when you change the shock lengths. So the way you are testing your up travel has absolutely no bearing on how the system will react with all the components are installed like they need to be. If the shock that you have chosen has a shorter collapsed length then the lengths that we recommend then you will need even more bump stop then what our recommendations are to keep the shock from bottoming out. When we lay out out kits and shock travel we base everything around 1/3 up travel (compression) and 2/3 droop (extension) so in the normal setup you will not see the tire touch anything on up travel but instead the new bumpstops should contact first (or shocks bottom out first if you do not have the proper bumpstops). Keep in mind that your shock being 1/2" shorter in compression then what we recommend would require at least 1/2" more bumpstop then we recommend for that shock length to stop the up travel where we had intended it to stop.
The 2.5" kit on a 2 door is going to gain you about 3.5" of lift due to the fact that the 2 door is much lighter then the 4 door. This being said your arms should be fine where they are or will need to be slightly adjusted to get the proper caster (which needs to be measured with the vehicle sitting on its own weight to get an accurate reading). An angle finder is a crude way of getting a ballpark on caster because there are a lot of variables that can impede your measurement. It can be used for reference but getting the jeep onto an alignment rack will be your best info to go by. Your best bet is to install your kit in its entirety then take it to the alignment shop and let them set the caster by adjusting the control arms.
RK
