I put Carbotech Bobcat pads on the front of my car a few months ago. Today I installed new rear drums/shoes, fresh fluid, and new 15/16 master cylinder. I think i may have not broken the pads in correctly, because when braking it doesn't seem to grab as much as I would expect. Does it sound to you guys like my pad are shot? Any suggestions are appreciated.

 

Did you do anything to your front brakes? I think you may just need to adjust your rear drums if you are looking for more "grab" Does the ebrake go up higher than normal?

 

The rear drums were adjusted when I put the new drums and shoes in. I will try to go back and check them. Any other suggestions?

 

Well, when I resurfaced my front rotors a few months after putting in my Bobcats, there was much less "grab," until I bedding them in at night doing 45-30mph slowdowns, and letting it cool off overnight.

Since you didn't do anything to your front brakes, I'm not sure what the problem is. What do you mean by "grab"?

 

I may just have expected a bigger difference between pads. Granted the brakes were shot when I got the car, and today was the only other time I've messed with the brakes since I put the pads in. I may have to drive one of my friend's cars and compare brakes. thanx

 

You need to bed them in. Instructions are in the box.... two it 2 or 3 times.

 

oh, ok, I thought you mentioned that your brakes "grabbed" less than it did before you replaced your MC, fluid, and rear shoes.

Did you adjust your rear drums by yourself? I just adjusted mine last week, and had it set to the point where the ebrake only takes 4 clicks to engage, instead of 10+. The pedal feels much firmer.

How long have you had the Bobcats, and did you bed them in according to the sheet that came with them? If not, daily driving for a certain amount of time will bed them in. MaddMatt on this forum works for Carbotech (he sold me the pads)

 

Give the Bobcats time. They need to do some magic thing transferring material to the rotors. Follows is a conversation I had with MaddMatt, who of course, works for Carbotech...

Matt: They're going to feel not so good for the first week or so.
Karl: Um...okay...what do I do?
Matt: Bed them in right and just drive on them. I promise, they'll become amazing.
Karl: Well, alright.

They are indeed amazing. If I do so much as glance at the brake pedal, the car slows down. A lot. If you bedded them in properly, and they're not working for you, I suspect something is amiss with the whole MC change...

 

[QUOTE=.RJ]You need to bed them in. Instructions are in the box.... two it 2 or 3 times.[/QUOTE
bobcats require no brake in....as far as i remember

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chad &raquo;</TD></TR><TR><TD CLASS="quote">bobcats require no brake in....as far as i remember</TD></TR></TABLE>

They do.

 

The biggest thing for Bobcats is they need time to establish a good transfer layer of material onto the rotors. Some pads accomplish this very quickly. Bobcats need time. Usually, I say follow the instructions in the box, and just drive them for a week or so ( a few hundred miles of normal driving) before you do anything really aggressive with them (autocross, whatever). If you change front rotors, or have them turned, guess what, you get to start over...

I hate drum brakes. I can almost 100% of the time attribute lousy pedel feel to rear shoes out of adjustment, or the ABS system (where applicable). If you have both....


Modified by MaddMatt at 7:40 PM 11/23/2004

 

So you had some rather hackish brakes, then installed the Bobcats and over the last few months nothing has gotten appreciably better? You then added a new MC and did a rear brake service and still nothing? Might seem silly simple but it seems most likely that the problem is either between the MC and the pedal (the booster??) or somewhere upstream from the pads but south of the MC. I think I would get a set of remaned front calipers first as that's typically not that expensive (and slop in the caliper can lead to very ineffective braking IMO) and next, if the brakes were in such ill repair when you got the car, you might want to check the hubs and bearings.

As for the Bobbies, on my 944, I cut a new set of rotors w/ them (new) and took the car out for 5 or 6 65-35 mph harsh braking - sorry Matt if that's not exactly right - I put the car up for an hour or so then went out for dinner (meaning same car) - they were (per Matt's warning) rather inefficient that first outing, since then they have been wonderful. Couldn't be happier w/ a street performance pad. Basically, I don't think I did anything technically right bedding or letting the pads cool or whatnot and they have been great - I doubt what you are feeling is the consequence of poor bed-in rather something else.

 

What does the 15/16ths MC do for you?
My (admittedly limited) understanding of the MC bore size will give you different points on the trade-off graph between pedal feel and stopping power. Larger bore = more fluid pushed, but longer pedal travel to do so. Smaller bore = less fluid pushed, but shorter pedal travel.
Perhaps that is wrong, or over simplified, but are you mixing up pedal feel with pad "bite"?

 

actually, a bigger bore mc will have less pedal travel, but will generate less pressure than a smaller bore mc, assuming they both use the same size brake booster