fot
[Top] [All Lists]

[Fot] brake pad and rotor discovery and update

Subject: [Fot] brake pad and rotor discovery and update
From: fubog1 at aol.com (fubog1)
Date: Wed, 11 Jul 2018 11:11:00 -0400
References: <1496073395.378283.1531254099121@connect.xfinity.com>
 Assuming that this is a type 16 caliper, they are all pretty much the same. 
There are 2 different style pads, "big" pin & "little" pin, dimensionally they 
are the same, and there are differences in the friction material shape. Some 
are rectangular, some are the shape of the lower half of a hexagon.
These cars need a pad with a taper because they run hotter and wear faster 
towards the OD.
If you're running a full rectangular pad (same shape as the backer), it's gonna 
wear towards the OD and get a taper in it in-to-out, and that's when the 
pad/piston alignment gets all poopo-kaka, the pedal gets long, etc.

I'm not suggesting that there isn't an issue with what you have discovered but 
the pad backer ends to the caliper clearance isn't a real close tolerance point.
Hope you get it sorted.
Glen

ps- Also I might be misunderstanding the problem...


 

 

-----Original Message-----
From: DAVE HOGYE via Fot <fot at autox.team.net>
To: Friends of Triumph <Fot at autox.team.net>
Sent: Tue, Jul 10, 2018 5:52 pm
Subject: [Fot] brake pad and rotor discovery and update



Hello Friends,
I have been finding out quite a bit about the unusual and developing front 
brake pad, rotor and caliper issues that I have discovered on my TR3.
 
What I found was that the Carbotech CT-57 pads were causing the problem.
  
The supporting or backing plates of the pads had been ground down at Carbotech, 
far under the normal plate width that I measured in 4 other production pads 
that I have on hand.  Besides that, they were not ground down squarely.
  
This allowed the piston to take tremendous side load under braking causing the 
uneven and diagonal wear pattern in the pads.  This also caused the rotor to 
contact the caliper as the pads took on heavy uneven wear.
  
The slot in the TR6 caliper is 3.095" and the four non-Carbotech pads sets have 
a plate width of no less than 3.082".  The Carbotech plates have an out of 
square measurement of 3.030-3.050".  That's as much as .065" clearance in the 
caliper slot.  
The plates have too much clearance.  I found that a maximum of .010" backing 
plate to caliper slot clearance is more normal.  One set of pads have only 
.005" clearance. 
 
Furthermore, the corners of the Carbotech plates and pads were ground down far 
enough that the lower end of the pads hardly made contact with the caliper slot 
allowing more stress on the caliper piston.


I have been going back and forth with Carbotech on this matter and I will be 
sending back the badly worn set along with a brand set that have the same 
production issues.  I bought the two sets at the same time last August.  


What I found is that any backing plates that show evidence of sanding or 
grinding marks should be measured for proper clearance, but that really, there 
should be no sanding or grinding marks...ever.


All of the other pads I have show no evidence of sanding or grinding marks.  
The previously shaped friction pads are cleanly attached to the backing plates 
and the backing plate is revealed around the friction material.  Only the 
backing plate makes contact with the caliper slot.  


It looks like I have to find another race pad supplier.  


Thoughts?


Dave H.
831-234-4928


 
_______________________________________________
fot at autox.team.net

http://www.fot-racing.com

Archive: http://www.team.net/pipermail/fot



-------------- next part --------------
An HTML attachment was scrubbed...
URL: 
<http://autox.team.net/pipermail/fot/attachments/20180711/e22c19b6/attachment.html>

<Prev in Thread] Current Thread [Next in Thread>