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I noticed in Chris's manual (in the pages he posted) that it said to take it easy on the brakes for the first few hundred miles. This is contrary to what I've heard as a break-in procedure (or bedding - whatever you want to call it). Is this because both the pads and the rotors are new or is it because Lotus doesn't think the average owner will know how to properly cool down their brakes when they park it?
 

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Bedding-in the brakes is simply making sure that the pad is well seated into the caliper. This is a moderately harsh procedure of applying heavy pedal pressure to the brake going forward, then backward. This happens only a couple of times and I'm sure it's done at the manufacturer.

Breaking-in of brakes is simply getting the pad and rotor surface "married" to each other. Both are not perfect surfaces. They need a few hundred miles to wear into each other so the pad will pick-up the surface features of the new rotor. Once you've achieved this "marriage" between the surfaces, you'll have maximum braking ability.

Bob
 

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This is from the AP Racing web site, not sure if the Elise even has AP discs (calipers, yes). I don't know if the Elise owner's manual conflicts with this info, but AP's advice seems pretty good.
http://www.apracing.com/roadcar/brakekit/bedding.htm

Disc Bedding
All cast iron brake discs need to be bedded-in to ensure heat stabilisation and improve resistance to cracking. Cracks or even disc failure can occur during the first few heavy stops if careful bedding is not carried out. AP Racing recommend the following procedure:-

ROAD CAR DISC BRAKE BEDDING IN PROCEDURE
Bedding the disc from new or stress relieving the cast iron disc after it has been clamped to the mounting bell is of paramount importance if premature warping is to be avoided after the brakes are used to their full potential.
AP Racing discs are produced from the same castings as our normal race discs, but when used in the controlled area of motor sport it is easy to instruct a driver to gradually bring the disc up to working temperature with some moderate braking over a small amount of measured laps, progressively increasing his braking effort until an Engineer assess the disc visually or by temperature readings.

For road car installations the process needs to be as follows:-
For the first 10 miles, light braking from 50/60 mph down to 30 mph if possible in blocks of 5. Do not attempt any high-speed stops down to zero at this point, as only the faces will heat up with the mass remaining cool along with the mounting area. For the next 100 miles increase the braking pressures similar to stopping in traffic, again avoiding if possible full stops from above 70 mph. By now the area around the mounting bolts should be a light blue temper colour. This is a good indication that the correct heat soak has been achieved. For the next 100 miles gradually increase the braking effort after this full power stops can be used. The disc should now be an even dark to light blue temper colour, depending on the pad type and the braking effort being used during the process. This process must be completed before any race circuit use.
If used at a Track day the following points must be adhered to so as not to warp the disc.

At the start of a session use a minimum of one warming up lap for the brakes i.e. gradually increase the effort at each corner and do not drag the brakes under power as in left foot braking.

Use at least one cooling down lap at the end of the session and if possible stay off the brakes.

Do not leave your foot on the brake when parked in the paddock after a track session. If you do, the hot spot created by the pad can distort the disc in that localized area causing a high spot, resulting in vibration under braking.

On the majority of car installations, race circuit use can be more exacting on the brake system than a fully prepared race car due to the following:-
None or minimal cooling, increased chassis weight, longer braking distances due to driving technique or tyre grip.
Therefore it is very important to check your brake system thoroughly after such use. Bear in mind race cars on average cover less than 50 laps of a circuit before being serviced.

PLEASE BE AWARE THAT DISCS USED ON RACE TRACKS WILL BE SUBJECT TO HIGHER TEMPERATURES AND WEAR RATES THAN ACHIEVED WITH NORMAL ROAD USE. THIS CAN HAVE AN EFFECT ON THE LIFE OF THE DISC, ESPECIALLY IF HIGH TORQUE COMPETITION PADS ARE USED TO REPLACE THE ORIGINAL FAST ROAD TYPES SUPPLIED WITH THE KIT.
DISCS ALONG WITH PADS ARE CONSUMABLE ITEMS.
 

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The VAST majority of new brake pads are subject to "green fade". This is when at a relatively low temp the resins in the pad boil off. As a driver this is quite ALARMING! The brakes will be working fine and then on the next application it will feel like they've been greased.

Auto makers generally recommend the gentle break-in method. It is SAFER for the general public (lawyers at work here). But, in racing you don't have the luxury of driving a hundred plus miles bedding in pads. The common bedding process then is to delibrately put the pads through heat cycles to burn of the resins.

Basically, find an open stretch of road and do some 50-60% stops from 20-30 mph. This will put some heat into the pads & discs. Continue to do this until you feel the brakes start to fade. Then from about the same speed do a hard stop.

Now let the brakes cool - drive slowly or stop.

Do the same proceedure. Each time going a bit faster on the final hard stop.

It should only take 2-4 cycles to burn off the resins. You'll be able to tell because you'll won't experience any "green fade".

Again, find a clear open stretch of road. You can only imagine if auto makers tried to instruct the general public to do this what would happen! There'd be wrecks, warped discs and who knows what else!
 

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I would suggest you use the following procedure, it is what I now do and I have never had brake problems after new pads and/or disks. This was recommended by Nick Adams on the Lotus Life BBS when he used to answer the technical questions on it. I assume the Alastair and Dave he refers to are McQueen and Minter. Basically if these guys don't know the best way to bed in pads on a Lotus, then who does?


Alastair and Dave recommend the following procedure for bedding Elise brakes in:
With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together. Once this has been done, check the surfaces of the discs and make sure here are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much. Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot. On the third stop come to a halt and keeping your foot on the brake press the brake pedal down as hard as you can and hold it there for at least a couple of minutes, don't apply the handbrake. This hurts if you are doing it right! This will bed the pistons, shims and pads together and will compress the pad material, giving a hard and repeatable pedal. Once the 2 minutes have passed, release the pedal and go for a short drive, using the brakes as normal to let everything return to normal temperatures. The brakes are now fully bedded in and ready for use in anger. Recompressing the pads once every few thousand miles to the above procedure will help keep the pedal firm, especially if you don't normally use the brakes hard.
Cheers, Nick
 

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Wow, I'm really surprised about the part that instructs you to clamp on the brakes when they are hot. Sounds like a recipe for pad deposits if you ask me.

Everything else seems spot on, except I try not to use the brakes at all on the trip home. And if they're still warm when I get home, I roll the car a few feet after 20 minutes, so the pad rests in a different area of the rotor.

Best,
John
 

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I've always been told clamping a hot rotor is bad for both the pad deposits and rotor cooling.

I think the intention in doing it was that you 'use' the heat to squeeze all the caliper/pad/smurf-sh*t parts together and get less play.

I dunno.. more conflicting break-in recommendations, all from reputable people.
 

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For track use, you will want to use Swizz's method. I don't think it is contradicted by the StopTech article, which is informative. (it is very interesting that he says there really are no actual "warped" discs- just ones with uneven deposits. ) No-one at the track will use their emergency/parking brake after a hot session as this will lead to deposit build-up. When bedding the new pads I was careful to cool them down on the way home and not use the parking brake afterwards.

From personal experience, I had horrible shudder on the track in my NSX after several hot laps (using stock brakes and pads). I upgraded to Axxis pads (not full race pads) and had NO shudder or fade using their recomended bedding-in procedure (i.e. Swizz's method). I was especially pleased because this was on the same OEM rotors (un-machined) which had produced such horrible shudder before on the track.
 

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DCNSX said:
For track use, you will want to use Swizz's method.
Just thought I would point out my name is Bill and I live in Switzerland which is where the Swizz comes from. and before anyone does a G W Bush, no Switzerland is not a county in England :D
 

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oops- Bill Swizz- I just read your post more thoroughly- and had not heard of holding the brake for 2 minutes to compress the pads. Is this an Elise-specific procedure? For which cars (early Euro or U.S./Federal?) I believe the early Euro Elises had different (non-iron?) brake rotors than the Federal cars have. Can you clarify? FWIW, the Federal cars also have power-assist which the early Euro cars did not.
 

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I'd not heard of this technique before Nick Adams posted it on the Lotus Life BBS. Some of you may have met Nick as he was over in the US at some of the shows and as you will know he was heavily involved in the development of the US elise.

He gave this advice a couple of years ago and by then all new elises had steel brakes, the MMC brakes on early elises did not really need this technique as the pads last for 100,000miles. I switched mine to steel brakes a couple of years ago as the MMCs could not deal with sticky tyres as the surface can melt on track and since then have always used this technique to bed brakes and have had no problems.
I guess the assisted brakes you guys have mean that you would not need to press so hard on the brake pedal but I doubt it would make any other difference as the disks and pads will be the same as the Euro spec ones.
I don't know if this is an Elise specific procedure, all I know is that it works for me and was recommended by people who know the Elise better than any of us normal mortals do.
 

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So, can this proceedure be done at any time? Or is it necessary to break in the brakes as nearly the first thing I do with my car. If that's the case, does anyone know some fairly well deserted roads in Jacksonville :D
 

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I do exactly as Bill has posted - the Nick Adams advised method on each new set of pads/disks - never had a problem - works great, gets rid of squealing quick too
 
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