Update on our track pads and the brake pistons - good news!

[MINI135i]

Originally Posted by scottn2retro

I'd be interested on an opinion on this as well - we have always used the stock backing plates with the racing pads.

Did you just forceably remove the OEM backing plate from the stock pad for use on the race pad? It seems aggressively glued to the OEM pad and possibly difficult to remove?

[pkcormier]

Hammer your stock pads on the track and the heat will melt the backing plate glue and the plates will fall right off. That's what I did, albeit by accident. I was then using HT-10 pads for track days without the plates and started to chip one of my piston inserts. I put the stock metal backing plates on the Hawk pads for my last track event and I didn't notice any further damage.

I don't know if this problem will persist with the HT-10s manufactured by Hawk, but the older turner version (2008) required a little bit of grinding of the pad to get the backing plate to fit. Think if it this way, turner used the profile of the stock pads with backing plates on to cut out the HT-10 pads. For a perfect fit they would need to cut pads to the dimension of the stock pad only, without backing plates.

[MINI135i]

I have the new HT-10's made by Hawk for the 135i.

They worked well on the track but there is an initial clunk, when moving forward and the first brake pedal action is initiated, which sets the pads in the most upward or forward positon. If you go in reverse and brake you can move them slightly downward again. We are probably talking 1-3 mm at most.

Point being there is a slight movement with the pads initially. Once in place they seem to brake all day long with no movement as long as you don't reverse the car, brake and dislodge them . The ceramic inserts seemed to do fine after the track day with the new pads, I noticed no change or chipping of the piston. I still would feel a little more comfortable with a backing plate becuase of that initial movement, as I'm sure it puts some shear forces on the ceramic pistons.

I am in discussion with Hawk regarding this issue and whether they consider it normal or not.

[pkcormier]

The turner HT-10s I used were also loose and rattled. The rattle went away under braking, obvioulsy. I assumed this could be a problem since the pad would be pressed against the rotor in different spots depending on where they were floating at the time I depressed the brake pedal. Not good for consistent braking since the rotor and pad would never be perfectly flush. This was also one of the possible culprits for the damaged piston insert in my opinion.

I fixed that by bending the metal tension tabs on top of the caliper bridge. Just push them down a bit and they will put more resistance against the pad. The hole in the top of the pad did not line up well with the pins in the caliper. Bend tabs first, then install pads, then insert pins. You may want to bend them back up a bit when you change to street pads, otherwise it is difficult to get the stock pads back in place.

[MINI135i]

I think the issue with the new Hawk pads are less than you are describing pertaining to the old ones, but definitely some similarities.

It will be interesting to see what Hawk says, I'll report back on what they conclude, as they are supposed to get back to me.

[m3bs]

It's not uncommon for HT-10s to rattle some, especially in the rear, since they don't have the spring on the back to lock them onto the piston. Never had a problem with them on the track, and I never run them on the street, except to get gas off-track. I've been using them for almost 10 years on my E36 now.

[MINI135i]

Used a lot of Hawk pads in the past and this particular movement seems a little different than the normal race pad rattle. Also, specific to the front pads only.

Talked to Hawk today. Probably a non issue, they think the lack of backing plate/shim allows a small amount of play but should not cause any problem. They are going to take another look at fitment just to make sure the ceramic pistons are protected from any adverse shear forces.

Again, everything worked well at the track and the pistons were fine, it might just take getting used to a "new" race pad noise. We'll see if Hawk has any further insight after testing my specific complaint. I will keep them updated as I track more in the future. Hawk has always been super helpful over the years, thanks Hawk.

[scorcherjf]

So have you guys found a good track setup for brakes? I just chewed out my stock brakes at the track and I'm looking for a track set that won't give me issues =)

[m3bs]

Originally Posted by MINI135i

Hawk has always been super helpful over the years, thanks Hawk.

Good to hear. Guess I need to talk to them about why I have to grind off the backing plate for my Stoptech fitment.

[BerkTechnology]

06-09-10
Update on the latest Hawk pads on the Berk Technology 135i race car. We went from the custom built Hawk pad to the "factory" Hawk pad for the front rotors. The good news, the built in packing plate on the pad has the correct flat areas so the piston has an even surface to seat against. I don't suspect that any of you will have a piston cracking problem with these new pads. But.... We now have the "clack!" from the movement on the front pads during your first stop. When you reverse & brake, it will unseat the pads and you'll get another clack! on your first initial stop when moving forward.

We didn't have this with the custom pad or the OEM pad. I have pics of the custom Hawk pad, OEM Hawk pad, and OEM pad all lined up. Give me a sec to post....

[BerkTechnology]

LEFT TO RIGHT:

OEM BMW Pad, custom Hawk pad, OEM Hawk pad.

Notice the correct location of the backing plate reliefs on the latest Hawk pad. You can see where the pistons hit on the custom Hawk pad in the center. This is my theory on why Scott & Ralph had issues with their ceramic pistons cracking. Ceramics = heat resistant but brittle.

Hope this helps guys! And happy racing to you all!