Thanks a lot, Ashley. This is excellent information.
Dave H.
Sent from my iPad
> On Jul 11, 2018, at 9:49 AM, Ashley Page <apage at prosystembrakes.com> wrote:
>
> All good points.
> I have been in the racing brake business for nearly 25 years and worked on
> them for the 25 prior to that.
> Just adding a few points that are industry standards in my work. Some have
> been pointed out in emails in this thread ? all good. Hope you find this
> useful.
>
> There should be some margin between the friction and steel back plate on the
> ends where the pad abuts the caliper.
> The pad should never be loaded against the pins that the pads hang from. The
> pins are there just to keep the pads from falling through - not to take
> braking torque. Sadly some pads might need the oval holes opened a little to
> avoid this; so inspection of all pads is a must.
> The pad should have .5mm (.020?) float end to end in the caliper to insure
> against drag or hanging up at any temperature.
> New pads should also have after installed .5mm (.020?) float or slop between
> the caliper piston or brake rotor and the pad to prevent drag.
> The pads should be loose in the caliper and able to be removed with two
> fingers.
> Pad overhang (friction above the OD of the rotor) or under hang (below the ID
> of the rotor) is not good. If its not chipping away during track use then
> knock of the overhang after each event. It can cause piston knock back and a
> long pedal and or overheating ? in the worst case. You can easily file the
> friction to the correct radius ? at the expense of a cheep new file per box
> of pads depending on the friction and size. Don?t use your favorite file for
> this.
> Pad steel backing plates are made in several ways, stamping, fine blank
> stamping and, the best, laser cutting. The problem with worn tooling used to
> stamp or fine blank plates (unfortunately common with old pad shapes) is that
> the edges of the plate where they abut the caliper are not flat and square.
> Instead of a ?fine? edge it looks like its been torn and the pad hits on a
> sharp corner. This starts to put a groove in the caliper abutment area which
> is not good. If your pads only have less than .020? float end to end and the
> plates look like crap on the ends then its advisable to file or belt sand the
> ends of the plates to be closer to square and flat. If the friction is even
> with the back plate end it can help cause delamination of the friction from
> the plate.
>
> The pads we deal with are very old shapes and for the most part today not
> subject to inspection by OEM?s such as Ford etc. In other words they are just
> made in small quantity or in some cases carved out of a larger donor pads and
> sadly some that do this don?t pay attention to details.
>
> But I am not throwing stones at random. The pads mentioned are all good and
> work well in the vintage and club racing world. Its just that some pads slip
> through with problems mentioned. Just a few things to look for in addition to
> all mentioned prior.
>
> Also with some brands if you notice a loss of stopping power look at the
> pads. If they look glazed over then find a smooth piece of concrete somewhere
> in the paddock or driveway and using a figure 8 pattern lightly grind away
> the shine on the friction and in most cases they will perform like new. Only
> takes 2 or 3 figure 8s to clean them up ? don?t overdo it.
>
> When the pads are new mark them so that they spend their life in the same
> place ? i.e. left outer, left inner, right outer, right inner. If you move
> them around to even out taper or for other reasons you will create a friction
> surface that is not flat and that is not good.
>
> Ashley Page
>
>
> From: Fot <fot-bounces at autox.team.net> On Behalf Of DAVE HOGYE via Fot
> Sent: Wednesday, July 11, 2018 10:36 AM
> To: timmmurphh at gmail.com; Friends of Triumph <Fot at autox.team.net>
> Subject: Re: [Fot] brake pad and rotor discovery and update
>
> Hi Tim,
>
> Just to clarify, the calipers on my TR3 are the 16PB TR6 units. They are
> similar to the 16P, but the P calipers have 1/4" pins and the PBs have 3/16"
> pins. The PBs also have a more durable flush seal design that I like. I
> open the pin hole to 1/4" for easier pad selection. If I get a set of pads
> with 3/16" holes, I just open them to 1/4". The PB caliper are sometimes
> referred to as "metric" because the mount holes and the bolt are metric
> sized.
>
> There shouldn't be any evidence of sanding or grinding marks around the edges
> of the pad backing plate or on the friction pad. If there is, they are most
> likely undersize.
>
> I have 4 sets of other pads. 2 different Moss compounds, 1 Hawk Blue and an
> old set of Raybestos that are still new in the box. None of these pads have
> any evidence of sanding or grinding on the plate edge. The edges are cleanly
> sheared.
>
> Also, the plates should be well proud of the friction material and they are
> on these 4 sets. On the Carbotech pads, the plates have been ground almost
> flush to the edge of the friction pad. So the pad edge is making contact
> with the caliper slot. Not good.
>
> It totally sucks that I have had to discover and study this matter. This can
> be regarded as a serious oversight from Carbotech. This could be
> potentially dangerous. I noticed this through a routine check after an event
> when one side seemed to be dragging more than the other.
>
> Dave H.
>
> On July 11, 2018 at 6:36 AM timmmurphh at gmail.com wrote:
>
> Thanks for this report. We have had some issues with the Carbotech pads on
> our TR4 at Blackhawk and the Kcup. We use the CT2-XP10 compound. I will
> check our pad to caliper slot clearance. Does anyone know offhand of the
> slot on the 16P calipers on our TR4 is the same as the TR3 at 3.095??
>
>
>
> Tim Murphy
>
> #317 TR4
>
>
>
> From: Fot <fot-bounces at autox.team.net> On Behalf Of DAVE HOGYE via Fot
> Sent: Tuesday, July 10, 2018 3:22 PM
> To: Friends of Triumph <Fot at autox.team.net>
> 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
>
>
>
>
>
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