Bicycle Mechanics - lack of braking performance

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MattG42C
08-05-10, 11:52 AM
I ride a 2005 Specialized Roubaix Elite, 105/Ultegra mix (brakes are 105, levers are Ultegra.) A couple days ago, I test rode a new 2011 Roubaix with the SRAM Apex group. I'm not sure if they were Apex brakes, or just another brand - they were not labeled.
Anyways, on my test ride, when I applied the brakes, I was like whoa! The brakes were awesome compared to mine. Subjectively, I felt like the bike was at least twice as quick to stop.
Back to my bike, as I said, I have 105 brakes, Kool Stop Salmon pads that were new this year (<1000 miles,) '06 Ksyrium Elite rims, and Ultegra brifters. The brake cables are original (about 4000 miles.)
So, my question is - are newer brakes that much better, or do SRAM brakes behave differently, or more to the point, is there something wrong with mine? Stretched (old) cable? Dirty rims? Needing adjustment?
Thanks in advance for any help,
-Matt.
BCRider
08-05-10, 12:13 PM
Could be a combo of one or more of those things you mentioned. Could also be that the pad faces need cleaning and scuffing up to expose fresh material. Could also be that the other brake calipers or levers use a slightly different leverage ratio so that you move the lever a little more to move the pads a given amount. A 10 to 15% difference would be immediately noticable. Or the controls may have been set up so that you gripped the levers further out towards the end of the lever compared to your bike. That alone can make a huge difference if your bike puts your fingers up near the hood and the other bike had you using the very end of the lever.
demoncyclist
08-05-10, 12:16 PM
I would look at the rims first. Have you ever scrubbed them down with a scotchbrite pad? They can get covered with an oily film from the road, and that can certainly effect braking performance. Just some Dawn in water and a scrubber will work wonders.
MattG42C
08-05-10, 12:22 PM
I would look at the rims first. Have you ever scrubbed them down with a scotchbrite pad? They can get covered with an oily film from the road, and that can certainly effect braking performance. Just some Dawn in water and a scrubber will work wonders.
I've wiped them down, but haven't tried the Dawn trick. Thanks for the tip!
BarracksSi
08-05-10, 06:30 PM
Pads. Replace whatever's on the Sram bike with good pads like those Kool-Stops.
Carbonfiberboy
08-05-10, 08:14 PM
Stiffness of the caliper makes a big difference. Also, the test bike may have had more aggressive pads, which I have found to increase rim wear. Also, as was said, leverage ratio makes a big difference. In all those things, except for the caliper stiffness, there are trade-offs. TANSTAAFL.
MattG42C
08-05-10, 08:45 PM
Thanks for all the input. I did the dish soap trick before my commute home... while I can say there was probably improvement, it wasn't dramatic. I think I'll look at the pads and the cables next (they do look a bit on the rusty side,) and if nothing changes, I'll have to chalk it up to the leverage ratio.
1nterceptor
08-05-10, 08:58 PM
One thing that wasn't brought up are the tires.
I'm guessing they also could have an impact on braking.
I'm talking about the brand/model and also size 18/23/25.
MattG42C
08-05-10, 09:00 PM
Specialized All-Condition Armadillo Elite (700x23) ... about 1000 miles on this set so far.
the_don
08-05-10, 09:17 PM
cable friction makes a big effeect also.
I bought a used BMX a few years ago and the brake was horiffic, put new cables on and it worked fabulously.
GoSharks
08-05-10, 10:02 PM
Pads. Replace whatever's on the Sram bike with good pads like those Kool-Stops.
I think you misunderstood the OP...
Anyways, at least with Rival brakes, they come with Swiss Stop pads. No need to replace those.
BarracksSi
08-05-10, 10:18 PM
I think you misunderstood the OP...
Anyways, at least with Rival brakes, they come with Swiss Stop pads. No need to replace those.
Nope, I think the OP doesn't know what question he's asking.
He has Apex, not Rival; and there's no saying that the calipers are even Apex at all since he says they're unmarked.
The only time I would recommend changing calipers is if the ones on the bike don't have a centering screw. Dirty cables affect feel, yes, but not stopping power (not unless they rust through and snap, anyway). Road bike tires are also so skinny that any differences are relatively slight.
Pads make the most difference. They do the most work. Swap out crappy unbranded pads for good ones (Kool Stop, or Swiss Stop, or even the current-gen Shimano DA and Ultegra pads) and braking performance will be as good as it can get on a road bike. I couldn't justify ditching the cheap Tektro calipers on my last bike after I put good pads in.
BarracksSi
08-05-10, 10:27 PM
BIG edit - let me take back the brand names of that last post.... :D
So he has Shimano, and tested Apex... I got it now... :innocent:
OP, what you're feeling is the better leverage of the Sram brake levers.
Take a look at your 105 levers and see how far down the pivot pin is located. Also check how your fingers wrap around the brake lever as you pull it.
When you get a chance, go back to a Sram bike (any one will do, their ergonomics are the same) and look at how much higher the pivot is, along with how your fingers reach them.
Half the reason I want Sram (and Campy) shifters is because of the great brake leverage. It has nothing to do with the calipers and everything to do with the pivot points of the levers.
I still think the OP didn't know what to ask, and only the person in the second post alluded to the leverage of the controls.
BarracksSi
08-05-10, 10:43 PM
(re-reading it again -- yup, more people than I thought had mentioned leverage)
Here's the 5600 105's that I had (my current 7800 are the same):
http://img.photobucket.com/albums/v201/BarracksSi/Bike/IMG_3052.jpg
On the hoods:
http://img.photobucket.com/albums/v201/BarracksSi/Bike/IMG_3050.jpg
In the drops:
http://img.photobucket.com/albums/v201/BarracksSi/Bike/IMG_3051.jpg
The last pic is a lot like Sram levers from the hoods.
MattG42C
08-06-10, 07:08 AM
I suspect what I most felt was the differing leverage points as you say, but I wanted to make sure there wasn't something wrong with my brakes. The cables are original (5+ years old now), so I may look at swapping those. Other than that, I'll wait until I pull the trigger on the 2011 Roubaix Comp Rival. :)
BarracksSi
08-06-10, 09:45 AM
What you can do for now (and some will disagree with me on this) is adjust the brakes so they're a little "loose".
By that, I mean to open up the calipers a bit so that they won't contact the rim until you've squeezed the levers partway.
Don't open them up so much that you can squeeze the levers all the way to the handlebar, though. You'd want them to bottom out just before the shift lever hits the bartape.
I like setting mine up like this because I want my fingers to curl around the lever a little more, giving better leverage for my gripping muscles. If they're too "tight", my fingers don't get to use any more than half of their curl (so to speak) before the pads quit moving.
You really won't be losing any braking performance, either. Shimano uses rubber shims inserted into the same levers as ours as reach adjusters for riders with smaller hands, and they can still lock the brakes. All you'd be doing is using the same part of the lever's travel as shimmed levers use (say, the last half before hitting the bars).
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