Just got done with a brake upgrade on all 4 wheels consisting of powerslot rotors, stoptech street pads, SS brake lines and caliper bushing stiffening kit. Took it out to bed in the pads and a few miles later get the telltale signs of "warpage" - rocking steering wheel, pulsing pedal and spotty braking.

WTH?? I've NEVER had this happen to any other brand of rotors I've installed on any of my vehicles. Even the last cheap set of d/s rotors I bought off eBay ran true till the very end. I DO know how to properly bed in pads. I think these rotors may be retaining too much heat because I notice after a normal 30 minute drive they are sizzling hot.

So then I read an article about warping myth that powerslot has on their website which basically clears them of any fault in this and places all the "sin", as the article says, on the user. I think that while there is truth to the article, one cannot rule out the possibility of poor quality manufacturing.

I did notice that all 4 rotors have the mark of "sin", as the powerslot article reads, which is the imprint of the pad somewhere on the rotor. Powerslot claims this is the cause for "warpage", but I have seen this on all my vehicles rotors and I believe its just where the pad contacts the rotor for an extended time. I'm thinking in my case, the rotors are not releasing enough heat to allow the pad to remain in contact with the rotor for say, the time of a stoplight in traffic, and causing the issue.

I doubt I can please a case to the place I bought them from for exchange, so can these rotors be turned to eliminate the problem?

 

Not to be an ***, but did you do the install? Are you sure you did it correctly? I have never seen 4 new rotors warped so I would think that there is something else going on there.

What you really have going on is uneven wear. Did you bed the new pads in? You could have a stuck caliper as well.

http://www.stoptech.com/technical-su...nd-other-myths

 

I am thinking that it is possible the rotors were not 100% clean, and had a dirty spot ...this may have resulted in pad buildup when bedding the pads...
I would roughen/clean up the face of the rotors and rebed them.
Ofcourse this assumes the surface behind the rotor was 100% clean when you installed them....

 

If you threshold brake with this brand new setup, does the next stop you make after this feel different?

 

Pretty sure I bed the pads in properly. Ran it from 60 to almost 0 a few times quick (not ABS lock) with a few minutes in between runs. Felt fine, then a few minutes later back in traffic is where I started noticing the signs. That's why I'm thinking these rotors are not releasing the heat properly or possibly poor manufacturing. The install went fine, cleaned the rotors with brake cleaner before install. Made sure not to get anti-squeal juice or anything else on pads face/rotors. Everything torqued properly, lubed up the caliper pins, etc. I'm not ruling out something is wrong other than rotor(s), but like I said I've never had this happen on a new set before so forgive the frustration if it's evident. My next step is to put the Mini back on a lift and check all 4 calipers and runout of rotors.

@Alex@tirerack, I will have to try this and report back.

 

If they felt fine then I doubt they are warped. As I said, something else is going on there.

 

I probably don't even know enough to comment, but I'm convinced that it is really hard to warp thick iron rotors. The uneven transfer of pad material to the rotor during the bed-in process might be enough to produce the results you described. The darkened pad imprint left on the rotor suggests the hot brake pad was left against (or very close to) the hot rotor when the car was stopped. Maybe you held the brake pedal down while stopped at a red light soon after some heavy braking? Or perhaps the caliper didn't fully release the pad from the rotor. New pads and rotors were at full thickness, so remain fairly close to one another even when the brakes are released.

I think it would be very unusual for brakes to get that much over-heated following any of the usual bed-in processes. Maybe you didn't drive quite far enough between hard braking episodes to allow the brakes to fully cool down.

I'm not suggesting that you're necessarily to blame, but there seem to be a limited number of suspects in this case: something wrong with the rotors or pads, their installation, or the bed-in process.

 

Another thought would be? Did you replace the brake fluid? Could the caliper/s be corroded internally? A different direction. Hopes this helps.

 

I ran into a similar problem. In my case rust/crud was left on the hub from the old rotor making the new rotor to appear warped. Wire brushing/scraping the mating surfaces between the rotor and hub allowed the rotors to sit flat.

Good Luck,
-jim

 

I may be mistaken but I dont think your supposed to come to a complete stop when bedding. I wonder if that could be a contributing factor?

 

He did say "almost" 0.

I'm a bit concerned with that bedding process. I've never seen a recommendation to bed in the pads by slowing rapidly from 60-0 right off the bat. Most recommend some specific pattern of near stops from speeds more along the lines of 25-40mph initially then, in some cases, somewhat higher. It looks like stoptech does actually recommend that process, but could the heat from that process have left deposits on the rotors?

--Matt

 

So I had the rotors checked for runout and they all checked out fine (the passenger front was only a few thousandths off). This has got me baffled now. I put everything back together and made sure and cleaned the hub surfaces, re-lube the caliper pins and torqued everything to spec. Steering wheel shake, spotty braking and pedal pulse are all still present after I reassambled everything.

I'm considering it could be due to the caliper bushing stiffening kit I installed while doing the brakes. I also have an issue where the ebrake cables are not fully releasing the rear calipers when the handle is dropped. It's not a crazy grip, but enough to not allow the rear wheels to spin freely. I notice if I put my thumb with a bit of pressure on the caliper spring where the ebrake cable connects to, the wheels can spin free. I'm guessing I have to adjust the ebrake, but could this cause my symptoms?

Those two things are all I have left to check out. I'm planning on replacing the stock caliper pins and then replacing all my old rotors/pads (luckily I kept them).

 

You need to replace the cables... This is not uncommon but t is a bit of a pain to do.