Brake Calipers: DA vs. Ultegra

[skootaroo]

105 10s brakes fade during an emergency stop over about 25km/h, I'm pretty happy with the overall performance but if I really use mine to the limit I can "feel" the temperature rise as the pads get softer.

 

[hd reynolds]

I heard of a guy who weighted 265lbs and was debating on drilling holes into his brakes to save a few grams. I was LMAO.

Speaking of drilling holes in b. claipers, The 07 Record seems to have a lot of them (tho not exactly holes). They're so light I could swear they're approaching the weight of Zero Gravs.

 

[alienator]

105 10s brakes fade during an emergency stop over about 25km/h, I'm pretty happy with the overall performance but if I really use mine to the limit I can "feel" the temperature rise as the pads get softer.

Then you'd better change the pads because the 105 calipers have got nothing to do with what you're experiencing.

 

[1id10t]

Interestingly I had a situation yesterday where I was speeding down a hill on my commute home. I was in the inside lane with only one car about 20 metres ahead of me. There was plenty of traffic to my right though. The motorist in front of me decided to stop for whatever reason. I clamped down on the brakes (Shimano 105s with stock pads). I still had too much momentum so grabbed even harder on the levers. The back wheel then started drifting to my left and then the whole bike felt as though it was sliding (first thought was i'd locked up the wheels but who knows as I wasn't going to look down). In the end I released the brakes and steered in between three cars and around the outside of them. Must go and buy a lottery ticket now.

 

[dhk2]

Interestingly I had a situation yesterday where I was speeding down a hill on my commute home. I was in the inside lane with only one car about 20 metres ahead of me. There was plenty of traffic to my right though. The motorist in front of me decided to stop for whatever reason. I clamped down on the brakes (Shimano 105s with stock pads). I still had too much momentum so grabbed even harder on the levers. The back wheel then started drifting to my left and then the whole bike felt as though it was sliding (first thought was i'd locked up the wheels but who knows as I wasn't going to look down). In the end I released the brakes and steered in between three cars and around the outside of them. Must go and buy a lottery ticket now.

That pretty much describes what happened to me in a couple of panic braking situations. Likely your rear wheel was locking up when you felt things getting out of shape. It's scary but controllable. Obviously, getting on the drops and pushing back to keep your weight back will help, but in a traffic situation no time for that.

I've followed cars enough to know that I can't stop as fast as they can. I don't think it's got anything to do with the brand of calipers or pads, but just the fact that limit braking is done on the front wheel. With a tire contact patch of 1-2 sq inches, and the problem of weight transfer trying to throw you over the bars, doubt there's any way to generate a stop as fast as cars can manage.

Tests of actual braking comparing bikes and cars from say 30 mph would be very interesting. Even with experienced riders, bet many have never practiced hard stops.
Sounds like you did everything "by the book"...and it turned out fine. Hope your good luck will continue on the lottery today

 

[dabac]

...I've followed cars enough to know that I can't stop as fast as they can. I don't think it's got anything to do with the brand of calipers or pads, but just the fact that limit braking is done on the front wheel.

I don't know about that, a car would see "the same" weight transfer to the front wheel(s) as a bike does. In fact, all cars have some sort limiter on the rears to prevent them from locking up as they would if brakes were applied 50/50. Some models have a well-deserved reputation of braking at the front and rusting at the rear.

With ...the problem of weight transfer trying to throw you over the bars,

Yeah, CoG vs wheel base is probably more important. Even a SUV or raised 4x4 would slide before it endo'ed. A rider also has to deal with the extra task of maintaining his balance, which obviously isn't a concern for the driver.

Even with experienced riders, bet many have never practiced hard stops.

It can be quite intimidating(not to mention the chore of getting up speed/up the hill again and again). But if you have the time to shift your weight back the braking power and the strain needed to keep your arms from buckling is quite amazing.
I remember the first road descent I did after having switched to a longer travel fork on my MTB, the compression was scary! You set yourself up, you apply the brake, and the front just sinks away from you. Lockouts are nice on climbs but even nicer on (road) descents...