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View Full Version : I know you're tired of this bike, but please give me a brake...


Kevan
09-29-2007, 06:14 PM
or at least a good suggestion for a brake. These relabeled Dia-Compes do nothing to stop the bike. Panic stops are not available with this model. So what's the solution? As you can see from the photos below this frame doesn't accept the modern recessed mounting hardware we all know and love. Take a look at all those washers and nuts, wouldja? I could go with the Paul's Racer center-mount centerpulls which are offered with a thru-bolt option, but I'm hearing mixed reviews about their setup and stoppage, and at $130 a piece? Come on!

Could it be that the rims have too smooth a brake surface for these brakes? You'll see I swapped out the traditional brake blocks for Koolstop mtb stoppers. What about the levers thmeselves, they contributing to my problem? They ain't Campys f'r sure, but who doesn't love that drilling (which is a joke on 25+ lb. bike).

Anyway, I'm open to ideas, kids.

I know, the first idea is a better frame, but that's a cop out.

Kevan
09-29-2007, 06:16 PM
.

michael white
09-29-2007, 06:20 PM
check toe-in, sand the pads a bit, and yes, the MA40 surface can be too slick for some brakes, but it wears quickly.

in the end, though, this brake will not brake like a modern brake, so I wonder if that's part of it.

Fixed
09-29-2007, 06:21 PM
bro nice bike ..cool make a great fixie

imho
cheers

regularguy412
09-29-2007, 06:45 PM
If they're rubber brake pads,,try softening up the rubber with some undiluted chlorine bleach (applied on a rag). This step is also useful in addition to the aforementioned sanding. What we're trying to accomplish with both these suggestions is to remove any possible glazing on the pad surface that may have occurred due to pad age or overheating. Be careful with the bleach. It's caustic to skin. I've used this method to improve braking on my TG. I have a set of the Open 4's on it, occasionally. Their surface is not machined. Stopping in the wet can cause your hands to cramp.

Mike in AR

Jeff Weir
09-29-2007, 07:28 PM
Sell the bike, get a new job, divorce the wife.

I hope I've been helpful

dvancleve
09-29-2007, 07:50 PM
Kevan,

Current style aero levers have more leverage on the cable and thus more force with the same pull (not wording that right, but the correct terms are escaping me). That said, plenty of bikes are set up with old style brake levers and (apparently) tolerable braking. I can tell you from personal experience that you will need to pull harder to stop a bike with non-aero levers and single pivot brakes than a current set up.

The second thought is that you can indeed use a modern allen mount dual pivot brake set on this bike. You use the front in back with the current nut and curved spacers. You use the rear in the front one of two ways. You can use is as is and put the allen nut *inside* the steerer so that the brake is bolted to the front of the crown. Sounds odd, but seems to work fine based on my one try and I'm pretty sure Sheldon Brown espouses that option. The other thing is to drill out the hole in the back of the crown so that a normal allen bolt fits through, then get one of those long ones for a carbon fiber fork and it should reach the shorter mounting bolt just fine. Either way will require a bit of tinkering to remount the front fender.

Doug

or at least a good suggestion for a brake. These relabeled Dia-Compes do nothing to stop the bike. Panic stops are not available with this model. So what's the solution? As you can see from the photos below this frame doesn't accept the modern recessed mounting hardware we all know and love. Take a look at all those washers and nuts, wouldja? I could go with the Paul's Racer center-mount centerpulls which are offered with a thru-bolt option, but I'm hearing mixed reviews about their setup and stoppage, and at $130 a piece? Come on!

Could it be that the rims have too smooth a brake surface for these brakes? You'll see I swapped out the traditional brake blocks for Koolstop mtb stoppers. What about the levers thmeselves, they contributing to my problem? They ain't Campys f'r sure, but who doesn't love that drilling (which is a joke on 25+ lb. bike).

Anyway, I'm open to ideas, kids.

I know, the first idea is a better frame, but that's a cop out.

samcat
09-29-2007, 07:51 PM
If I'm seeing them correctly, they look like pads designed for Vee brakes or Cantis... Dual compound Mt. Pads or Thinlines...

You need road pads and holders. See:

http://sheldonbrown.com/harris/brakeshoes.html

PH

Grant McLean
09-29-2007, 07:51 PM
Lose those levers.

The calipers are fine, it's the lack of mechanical advantage with those crappy
levers. Get some of the shimano BL-R400 levers, and you'll notice a big difference.

-g

chuckroast
09-29-2007, 08:51 PM
Maybe classic bikes are like classic cars no? Back in the day, we rode or drove things that seemed perfectly appropriate then but by modern standards they don't measure up?

Fixed
09-29-2007, 08:57 PM
bro
right hand front might help
cheers

Peter P.
09-29-2007, 08:59 PM
Could be the calipers, but I'm guessing you're limited to normal reach, bolt on brakes, which can be hard to locate in a reasonable quality level.

I first would try new levers. Drop bar levers can be designed for either sidepulls, dual pivots, or cantilevers. You need more mechanical advantage from the lever (the easier to find fix), so you need a lever that pulls more cable for a given travel. That may cure your problem. I forget which style lever offers that increased advantage; your LBS should know.

Next would be to hunt down a quality pair of brakes AND matching levers on e-bay. You could make it easier on yourself and convert your bike to recessed bolts by drilling out the back of the crown and the seatstay bridge. This will make available to you some of the more modern, dual pivot brakes.

big shanty
09-29-2007, 09:25 PM
get a couple of Ultegra fronts (about $15 apiece on Nashbar last I saw), hang onto the curved washers from your old calipers! Have a decent shop drill the back of the crown to accommodate the recessed bolt. The rear will just need a new standard nut. Done!

mpetry
09-30-2007, 08:22 AM
Your pads look OK, fairly new and dual compound. If money's a problem, I suggest you buy some replacement levers off ebay - these look OK:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=130157111426

and then carefully re-route the cables, under the bar tape, using new housing and inner wires (use the rear wire for the front, and get a new inner). The dia-compe cables are the best in my opinion. Bed the cable down (squeeze hard) before final taping. If you don't know how to do this, get help. Good adjustment counts for a lot and brakes are a critical safety item to say the least.

The other thing I noticed is that the brake pads are all the way "down" which is limiting the mechanical advantage available to "squeeze" the rim. What you might do is look for a used dual pivot front brake, since the front does 70% of the braking. The rear should be fine.

Here's a front caliper you can probably get cheep.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290163942753

Lastly, try using some steel wool on the rims, to break thru any crud that is keeping your pads from being fully effective.

Mark Petry
Bainbridge Island, WA

Kevan
09-30-2007, 09:15 AM
I have to say the pads and rim surface are pretty clean, maybe too clean in fact. I'll take up on some of the suggestions here though.

My underlying concern have been those levers. I think I'll attack them first. Mark, I like the look of those Ultegras and I saw that Soma too has a cool looking pair.

http://www.somafab.com/aerolevers.html

The shimanos 400's look all business, but are missing some panache. Any other makes or models come to mind that offer a flash of bling but most importantly stop the bike?

http://www.canecreek.com/scr-5_lvr.html

http://www.cambriabike.com/shopexd.asp?id=33015&page=CAMPY+RECORD+AERO+CARBON+BRAKE+LEVERS

thejen12
09-30-2007, 10:15 AM
Any other makes or models come to mind that offer a flash of bling but most importantly stop the bike?

http://www.canecreek.com/scr-5_lvr.html

I have the compact version of these canecreek levers and I love them. I found they really improved my braking and ability to modulate my braking. Perhaps that's because the compact model fit my hand better. They also come with gum hoods! Those and the Soma brakes are all made by Tektro, and the Tektro branded model is the cheapest, if money is an object. But the Cane Creek come with gum hoods! :D They also have a wide, very comfortable hood for when you ride with your hands up on the hoods.

Jenn