How easy should spherical bearings move? It seems like my turner RTABs are WAY too stiff, and seem to bind. They pop like crazy under load, and the trailing arm is very stiff to move (without spring and shock attached). These were a bitch to press in, so I'm not thrilled about having to remove them. All the other bearings (lower control arm, shocks) seem to rotate very easily. :help

Usually a spherical bearing that moves very easily is shot, or just not a quality part. "Very easily" meaning you just have to touch it with your hand and it will move.

To Keep tolerances tight, it should be stiff, but not seized...if its making noises, it prob bad.

I'd suggest going with an after-aftermarket spherical bearing. Hardware is the one thing that you want to get the best you can, $50 here and there adds up but it can be much more expensive if one fails down the road.

http://www.nhbb.com/ has some of the best bearings you'll find anywhere, if you can, i'd try to get bearings from them.

Aurora is pretty good, but you have to get thier high end aerospace quality parts, as they have some commercial and "economy" level parts that are significantly less quality (and price, which is why they are used so often in aftermarket). Thier aerospace line uses ptfe liners.

While at RRT we never used anything but NHBB if we had a choice. You pay for what you get, and in this case its superior bearings in most cases.

You have spherical bearing RTABs for the street?

I ran into a design issue when we were making ours (me, by hand, on a small lathe). It requires tight machining tolerances (+0/-0.001") to make sure the parts press in, but that then caused problems with the "breakaway torque" of the bearing inside the aluminum carrier.

The bearing will either loosen up over time, or you will get so irritated that you go back to rubber or urethane bushings. There are other solutions, but those are a trade secret of mine ;)

You have spherical bearing RTABs for the street?


Ummm ... no. This is for my mod level race car (the 95 M3) :)


I ran into a design issue when we were making ours (me, by hand, on a small lathe). It requires tight machining tolerances (+0/-0.001") to make sure the parts press in, but that then caused problems with the "breakaway torque" of the bearing inside the aluminum carrier.

The bearing will either loosen up over time, or you will get so irritated that you go back to rubber or urethane bushings. There are other solutions, but those are a trade secret of mine ;)

Ok, so you think that this is not an issue? I don't mind the noise (it is a race car after all), but I don't want to have other issues because of the high "breakaway torque" as you put it. They were definitly VERY tight to get into the trailing arm (had to freeze them for a couple of hours!)

Well the sound is an indication that something is not operating as designed. Do you see any abnormal wear on the bearing?

Can you see the interior liner, is it damaged?

Spherical bearings are usually not very loose, even small 1/2" bearings should require a screwdriver as a lever to get the bearing to move.

Just make sure its not seized or in the process of failing.

After its moved around a little, does it still have the stiction where the force to overcome its initial movement seems more than it should be?

Ok, so you think that this is not an issue? I don't mind the noise (it is a race car after all), but I don't want to have other issues because of the high "breakaway torque" as you put it. They were definitly VERY tight to get into the trailing arm (had to freeze them for a couple of hours!)
Well, the 'stiction' as Steve said is detrimental to optimum suspension operation. It's not going to kill the handling, but it is nonetheless not a good thing. The bearing will eventually get looser, but it could also encounter a problem before wearing out.

Since the press fit sounds like it was way too tight, the bearing is now compressed tighter than it was designed for. You will have to pull the RTABs back out and either machine down the OD to get it to be a lighter press fit, or clean out/grind the trailing arm hole to get a lighter press fit.