Brake Pads

[Doug_G]

I've actually discussed brake pad replacement with Tesla service, because one of my rear pads has a little chunk missing.

He told me that they always replace the pads and the rotors. That's because the rotors and pads conform to each other, and it's always something of a wedge - not vertical - because of how the pads engage. So when you change the pads initially only a part of the pad would be in contact. Probably what would happen is poor contact and the pad would wear very quickly at first. This would be true for any brake pad, of course.

 

[wiztecy]

I'd disagree with replacing the rotor with every pad replacement. If the rotor is deeply grooved or chatters when braking I'd have it resurfaced but not replaced. It only needs to be replaced if its been resurfaced so much that its out of spec and will eventually fail due to lack of metal thickness on the braking surface or if the rotor is warped from heat.

In all my brake jobs I've done I've never had to change out my rotors nor resurface them. I didn't have chatters or bad grooves worn in, I've had minor grooves and chose not to resurface. Mostly when rotors are resurfaced is due to them being glazed from being overworked. If I was racing all the time I'd resurface it to get that extra bite when braking hard to coming up tight through to the corners... I'll have to closely inspect the Roadster's rotors when I pull them for the pad change but most likely I won't touch them either.

 

[Tesla 940]

In all my brake jobs I've done I've never had to change out my rotors nor resurface them.

I totally agree. Only once did I HAVE to change the rotors - then again it was probably the fourth pad replacement and the car had 300+K miles. For general driving even if the rotors are slightly grooved, the pads will wear into the groves.

IMHO - replacing rotors and even resurfacing is a combination of CYA and increased revenue on the part of auto repair operations.

 

[Doug_G]

I know changing the rotors seems like overkill - I'm just reporting what Tesla Service said! There's nothing wrong with my rotors.

In the end I simply decided not to replace the pad, because it wasn't enough missing surface area to matter. Also it was a rear pad; I would have been more concerned about the front.

If I go to Carbotech pads then I'll just swap them, bed them in, and see how things work.

 

[wiztecy]

Doug, do you know the root cause of the chunk missing from the pad? Just a possible defect? You're up in Canada, possibly water got underneath the pad and the metal it mounts to, froze and then fractured off a chunk of material and eventually over time. Would be a pretty good size chunk down to the metal, not a chip. Who knows really but just a guess. I've seen small chunks missing on pads, typically on the edges caused from just bad material as well as being old and overworked.

 

[Doug_G]

Tesla thought that it had happened due to a very fast thermal cycle. Given that I sometimes take it to autocross and occasionally to the track it is a plausible explanation.

 

[frequencydip]

It looks like some companies offer "pre-bedding" for the carbotechs:
2008-2005 Lotus Elise Carbotech AX6 Front Brake Pads

Anyone care to comment on this? Thanks!

Pre bedding is unnecessary and throwing money away. All pads have to be bedded in with the specific rotor they will be in operation on. The bedding process does two things, it conforms the shape of the pad to the rotor, especially important if the rotor is old and pad is new. It is also the process of the new pad removing the old pad material important if switching compounds and it also coats the rotor surface with the new pad compound.

Rotors do not need to be replaced when changing pads and rarely resurfaced, normal cars almost never wear out their rotors. I have only worn out rotors when tracking a car, street driving just doesn't wear that much off the rotor or cause grooving or warping.

 

[wiztecy]

Can anyone confirm that the 2005-2008 Lotus Elise brake pads will crossover to the Tesla Roadster?

 

[strider]

Pre bedding is unnecessary and throwing money away. All pads have to be bedded in with the specific rotor they will be in operation on. The bedding process does two things, it conforms the shape of the pad to the rotor, especially important if the rotor is old and pad is new. It is also the process of the new pad removing the old pad material important if switching compounds and it also coats the rotor surface with the new pad compound.

+1 Was just about to post the same info and decided to read to the end of the thread

 

[frequencydip]

Can anyone confirm that the 2005-2008 Lotus Elise brake pads will crossover to the Tesla Roadster?

Yes, you are looking for pads that fit the Elise 05-08 for the Tesla Roadster.

 

[wiztecy]

Thanks!

 

[hcsharp]

I just found this on the Carbotech FAQ:

2. Do I have to resurface (turn) the rotors, or get new rotors?

If you have had another manufacturers brake pads on those same rotors; then you will ABSOLUTELY have to replace or resurface (turn) those rotors before installing the Carbotech brake pads.

If the rotors and drums are in relatively good condition, meaning they are smooth, flat, with no visible cracks, deep scoring, distorted, and with no other visible damage; and you have ONLY had Carbotech brake pads on them, then they do not have to be resurfaced or replaced.

@wiztecy are you turning your rotors? Their high performance street pads (Bobcat 1521) sound better for aggressive street use. Why didn't you get those? Or do you plan to track your car?

 

[wiztecy]

Thanks hcsharp for posting the info. Very interesting carbotech mandates having your rotors turned if running a different brand of pad. I'll take their recommendation and will be doing that. I ended up going for the AX6's. I don't track the roadster but it appears the AX6 work better at a lower temp (55 degree F ) and higher temp (1100 degree F) from what I read on the carbotech writeup which is better than the bobcat. The other difference I could see on the bobcat streetpad was that it has less dust and less noise. So the noise of the AX6 doesn't appear to be really an issue as discussed in this thread and it possibly may never occur. I really want the pads to bite and stop the roadster when I need them no matter if they're heated or not, and seeing how the roadsters are magnets for frontend collisions I want to eliminate that the best way I can. I'll post feedback on how they work, the dust, and noise after I get them installed. I ordered them on Monday so they'll hopefully be here before this weekend or early next week. Will take me 1-2 weeks to get them installed since I've got other projects queued up but I need to make brakes a high priority since I never know when I need that extra bite.

 

[frequencydip]

To get the absolute best result replacing or resurfacing the rotor will help, however it is not needed. You must make sure to properly bed in the pad but thats the only real requirement. I did not replace or resurface when I switched to the AX6 and it performed better than stock from day one.

 

[Doug_G]

Right. In my experience you just need to bed them in. The pads scrape off the old material and replace it with new. They might be squeakier than normal at first.

 

[Roger Reid]

Here is a photo of the box with part Carbotech AX6 numbers and contact info.

 

[Doug_G]

Here is a photo of the box with part Carbotech AX6 numbers and contact info.

Awesome, thanks!

Edit: Just ordered a set!

 

[strider]

I ended up going for the AX6's. I don't track the roadster but it appears the AX6 work better at a lower temp (55 degree F ) and higher temp (1100 degree F) from what I read on the carbotech writeup which is better than the bobcat.

So from Carbotech's FAQ: Carbotech Performance Brakes: Frequently Asked Questions it looks like the 1521/Bobcat pad would be better for me. I only daily drive my car. I may take it to Laguna Seca for a Refuel event someday but I could just install the OEM pads on it for that day (since they work fine when clean and warm). In the FAQ it lists the AX6 as working starting at 150F and the Bobcat as working starting at ambient. Do pads hit 150F just gliding over the rotors and so the AX6's would work when commuting?

 

[Doug_G]

150F isn't very hot, so one stop might do it. Also they will work fine cold; they just won't be optimum. The OEM pads aren't anywhere near optimum much of the time.

 

[wiztecy]

From what I read in other automotive forums people went to the AX6 from the Bobcat to get more bite from their brakes. That's what I'm after since I want to stop really really good. I'll give Carbotech a call today and ask about the initial startup temp and see what they have to say.