Another disc brake question

[Bernie H]

I have the discs installed on the hubs and the hubs on the swivel axles. I bolted the calipers to the axles, but do not have the hoses connected to the calipers. When I turn the disc and hub I can hear the pads rubbing against the disc. No resistance, just a rubbing sound. Should it be like this ?

 

[George Zeck]

There is always going to be some, quite minimal. Hard to diagnose over the internet on what is too much.

I think I'd look to see if the rotor stops spinning naturally (lack of momentum) or abruptly (catching or binding) - especially if it stops soon after you spin. I know this is all subjective, but ....

 

[Bernie H]

Thanks for the reply. It does bring up another question: I have new hubs that use tapered bearings. How the hubs and discs move depends on how tight the nut is on the swivel axle. I have it so that I can turn it by hand with some minimal resistance, but I certainly can't spin it. Very hard to quantify I know.

 

[Jim_Gruber]

You may need to back off a flat and add shims to get to the correct tightness. With wheel on you should be able to spin the wheel and have it rotate on it's own for several revolutions I would imagine without the drag of pads being in place. Again subjective. But there is a process in your tapered bearing install instructions, if not there should be, om measuring clearance to get to the proper tightness. Shims I am told can be found in the McMaster Carr Catalog. Part Numbers, Thickness, etc. no clue but someone will chime in.

 

[Bernie H]

Thanks Jim. If all else fails read instructions.

 

[Bernie H]

I contacted the maker of the hubs: JLHMorrisMinors in UK. The person who replied was very helpful. It seems that there is a 1mm spacer that, if needed, goes between the hub and the disc to center the disc between the caliper pads. Also the procedure for tightening the castellated nut on the swivel axle is to tighten the nut by hand, spin the disc/hub and tighten with a socket until the hub begins to slow. The thing to avoid apparently is over tightening.

 

[Joe Schlosser]

The big question is are you still using the spaces piece between the bearings.
The tightening method for the taper bearings is different when using this piece and it should always be used as it provides a stronger hub.
The method you described is not the correct one when using the spacer piece.
When using the spacer piece you need to shim the spindle so that there is zero free play when the nit is tightened down fully tight.
The hub should spin freely with no wobble

 

[Bernie H]

No, I am not using the spacer in the hub. The maker said that they no longer offer these.

 

[Joe Schlosser]

Your old set up should have had the spacer piece. I know they are difficult to come by if you do not have a pair.
After a lot of discussions on the Production racing board everyone came to the conclusion that they were a very important part of the hub design.
The spindle is not very strong without adding the spacer. Using it with tapered bearings and shims effectively doubles the thickness of the spindle.
Even though you are not going to put the track, you are using 50 year old English steel that could use all the help it can get

 

[nomad]

Agree with the advice on using the spacers and shimming. The same technique has always been used on MGB's. When setting them up I used to use a dial indicator on a magnetic base with a known shim pack thickness. All that was needed then was to measure the free play and subtract from that reading to the correct figure. When you had that you knew how many shims to remove from the shim pack. Job done,

Kurt.

 

[Bernie H]

Thanks to all for the advice. I now know how to handle my problem with the hubs. My next question regards the rack.