Brake pad overlap?

[Naybr]

In an effort to stop my front brakes squealing quite so much, I've just replaced the Greenstuff pads with standard ones fitted with soft shims and ant-squeal grease.

 

One of the things I noticed when removing the old ones was that they very slightly overlapped the edge of the disk leaving a small lip on the pads. I initially thought that this was because the old pads had been drilled out to take 5/16" pins rather than 1/4" ones. However I noticed that the new ones I have just fitted (and which have the correct size pin holes) are just the same.

 

Can someone advise me if this is normal please? It doesn't look quite right to me.

[Steves_TR6]

That does indeed not sound right !

 

Perhaps the disks fitted are not the correct size?

 

I found Greenstuff pads to be quite squeally when I had them previously, so you're not alone.

 

Disks are cheap and easy to fit, so perhaps have a measure to confirm they are correct.

 

I can measure a standard set for you if that would help?

 

Ps, what's your name and whereabouts are you ?

 

Steve

[BlueTR3A-5EKT]

If your discs turn out to be the correct diameter for the original spec of the car it could be that you have had TR3 caliper mounting brackets fitted. This would enable a slightly larger diameter disc to be used, as TR 3-3A disc are bigger diameter than TR 4A-6 (I am ignoring TR3B and TR4 as those cars used both sizes of disc during its life)

11 inch dia. disc on TR3/3A (279 mm)

10 13/16 inch dia. disc on all TR4A-6 (275 mm)

 

Your choice then is :- either fit TR3 discs to match the TR3 caliper mount brackets or source and fit TR4A-6 caliper mounting brackets to go with the TR4A to 6 diameter disc.

 

SC Parts give this info http://www.scparts.co.uk/sc_en/english-cars/triumph/triumph-tr2-to-tr4a-1953-1967/brake-hydraulics/front-brakes-tr3-from-ts13046-tr3a-tr3b-tr4-and-tr4a.html

 

Cheers

Peter W

 

PS The pad retaining pins on TR6 started life as 1/4" dia. then reduced in 1972-3 ish to 3/16" dia. If you have 5/16" dia pins you may have something even more curious fitted like odd ball calipers.

Edited May 24, 2014 by BlueTR3A-5EKT

[Naybr]

Thanks for your help guys.

 

Firstly, apologies for the typo. The pins are the larger standard 1/4" ones. I think they are the slightly later callipers (how can I tell for sure?). The car is a 1971 C/No CP54498 O btw.

 

I wouldn't have thought that there was space for a larger disk but its an interesting thought. Not sure how I can measure them accurately without taking them off the car.

 

The overlap is only about 1mm. at the widest radius of the pad, if you see what I mean. The amount of pad not in contact with the disk is minuscule and I suppose my real question is: How much does this actually matter..?

 

Steve: my name is Bryan and I live near Cambridge. The recently acquired TR6 is actually my third TR over the last ten years or so.

 

Bryan

Edited May 26, 2014 by Naybr