Rotor specification needed

[Michael Oritt]

I have BT7 front disc brakes on my 100 and I would like to know what the thickness of the rotors should be. I cannot find anything in the shop manual.

 

[Bob_Spidell]

I believe rotors prior to BJ8 were 3/8" thickness when new (BJ8 rotors are 1/2"). Hopefully, someone will confirm.

 

[Michael Oritt]

That translates to .375". My rotors mike at about .350-.360".

I ask the question because I am unhappy with my brakes' performance and am trying to determine if it is merely a matter of pads or something else.

 

[GregW]

I'll go with Bob's 3/8". On page MMM.4 of the manual (first paragraph) , the minimum thickness for the disc is .335"

 

[Superwrench]

Yep Should be .375 new

 

[TimK]

I recently installed a set of Moss's Gold ceramic pads and they work great, except for squeal, despite using the included anti-squeal shims.
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=70891

 

[Genos2]

According to workshop manual,100-6 & 3000 rotor min is .335 in or .38 mm. later BJ8 rotors were thicker.

 

[steveg]

I recently installed a set of Moss's Gold ceramic pads and they work great, except for squeal, despite using the included anti-squeal shims.
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=70891

Tim,
When you installed the ceramic pads, did you break them in?

The procedure is to do maybe 10 or 12 hard but not panic stops from 50 - 15 mph until you can smell the brakes.

I did this on the Centric ceramic pads on my 4-wheel discs and the car has never squealed ever.

There are also potions available at the auto parts store, which will work.

 

[TimK]

Thanks, Steve, I normally do this on all the other cars on which I replace pads. I do not think I did this on the Healey, however. I'll have to try it.

 

[TimK]

Thanks, Steve, I normally do this on all the other cars on which I replace pads. I do not think I did this on the Healey, however. I'll have to try it.

I finally got around to "bedding" the brake pads. It only took about 5 hard stops from 50-15. No more squeal. My apologies to Moss for the posted remark on brake pad squeal. Not any longer!