Bicycle Mechanics - more stopping power via dia compe brakes

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jamesss
09-25-09, 06:42 PM
I have just finished my world sport conversion to an alfine hub. It weighs 30 lbs and has some tall gears (52 x19) so i need some more stopping power. Can I tune up these old brakes to stop me and my bike faster?
700c x 35 tires
salsa delgado x rims
Retro Grouch
09-25-09, 06:49 PM
Probably not. Those arms flex too much to transfer very much stopping power.
I those on an old road bike. I shoe-horned some Koolstop pads mountain pads in there and it helped quite a bit.
New cables and housing will also help if the old ones are grunged up.
HillRider
09-25-09, 06:53 PM
Probably not. Those arms flex too much to transfer very much stopping power.
+1 They will never be really solid. About the best you can do with them is fit Kool Stop Salmon pads which should improve things somewhat.
jamesss
09-25-09, 06:58 PM
Ok thanks
squeeze mountain pads on there
fuzz2050
09-25-09, 07:17 PM
they will stop acceptably as long as you have some good pads (the koolstop ones everyone talks about are the best) and if you adjust them well. Truthfully, most any brake can throw you over the handlebars, as long as you set it up right.
Bianchigirll
09-25-09, 07:28 PM
are you using those 'suicide' levers? I would also try a better quality set of brake levers without the "safety" levers.
how do you like those rims? I got and Nexus 8, and frnt Dynamo wheels set with those rims.
OH yeah try some alchol or nailpolish remover on the rims to clean any oils and other stuff off.
also if you go to Harris Cyclery you can find a gear inch calculator
garage sale GT
09-25-09, 07:32 PM
Make sure you can grasp plenty of lever. Move the levers if you have to. Lube the cables.
I disagree with Marie Celeste's suggestion to remove the lever extensions provided the stock levers work well enough. Mine do, on my '85 World Sport, and they have extensions, though you do have to take up the flex.
Flex does not decrease force but you do have to keep the brakes well adjusted so that you could still be applying ample force after the flex is taken up, instead of bottoming the lever or not being able to grab it with a full fist.
Using the extensions themselves never provides full braking action but you should only use them when tooling around slowly. I also only ever use the part which is behind the pivot, not the part which points inward.
Bianchigirll
09-25-09, 08:05 PM
wasn't the "Marie Celsete" a ship found abandoned on the open seas?
jamesss
09-25-09, 08:06 PM
I like the Rims they are eyeleted(which is good) Im no expert but they roll smoothly and everything seemed smooth on the shakedown cruise Today.
Its mostly flat around here so the gear range is broad i may never use the top gear maybe across the bridge which has a long downhill run.
HillRider
09-25-09, 08:14 PM
OH yeah try some alchol or nailpolish remover on the rims to clean any oils and other stuff off.
Use alcohol or acetone to clean the rims but not nail polish remover. It's correct that many nailpolish removers contain acetone but they also contain some oils to keep from drying out your skin and that's the last thing you want on your rims.
BTW, I agree on not using the "safety" levers. I'd either cut them off or replace the entire brake lever set with better ones. They provide poor leverage and way too much flex.
The brake arms themselves are flimsy enought that the extra flex from the suicide levers is going to make lever travel excessive.
jamesss
09-25-09, 08:21 PM
I agree that the suicide levers are not as effective but they come in handy when rolling around casually
jamesss
09-25-09, 08:23 PM
would carb cleaner work?
HillRider
09-25-09, 08:28 PM
I agree that the suicide levers are not as effective but they come in handy when rolling around casually
The problem is more than poor effectiveness. You get used to using them and, when a real hard stop is called for, you don't reach for the proper levers. If the main levers are all you have, you are trained to use them at all times.
DannoXYZ
09-26-09, 12:56 AM
The other problem with suicide levers is the direction of their motion, upwards. To really make the brakes bite, you have to move your hands upwards and removing weight from the bars. When you really yank on the suicides hard enough to get decent braking, the only thing preventing your weight from flying forward is your thumbs. Many a people have made panic stops and have broken their thumbs and gone over the bars anyway... and end up hitting whatever it was they were trying to avoid; adding double insult to injury. During my 10-years at a shop, we saw at least one person come in a month with broken thumbs asking to "fix" their brakes...
johnknappcc
09-26-09, 01:52 AM
Truthfully, most any brake can throw you over the handlebars, as long as you set it up right.
+1, so very true.
fuzz2050
09-26-09, 03:17 AM
I have some time (insomnia) so I'll give you some more instructions
i) optional, new brake levers: buy a pair of Tektro brake levers, they should cost you $20 or so. The modern 'aero' design, which has cables leaving parallel to the handlebars instead of in the arch you have now, provides slightly more mechanical advantage, which can lend itself to a better feeling brake.
1) first required step: new brake pads, for the front at least. Don't know for certain, but I think Koolstop Thinlines should do the trick. Make sure you get them with a threaded post. Install these so the front of the pad is a little closer to the rim than the back (called 'toe-in').
2) replace your cables and housing: The new fancy stuff with the plastic coating on the inside works great, and makes your brakes feel (and stop) much better. Make sure it's brake housing (you only make that mistake once, trust me). Make sure the housing has no major kinks, and no steep curves, all while being no longer than absolutly nessesary. It sounds harder than it is.
3) Adjust your brakes: easiest way to do this, that I've found.
a) loosen the barrel adjuster on top of the brake about 6 turns.
b) hold the brake calipers together (use a 3'rd hand tool, a toe strap, a friend, just about anything)
c) use a 4'th hand tool/ pliers to pull the cable down as tight as you can. Tighten the fixing bolt
d) loosen the barrel adjuster again, and be careful not to send yourself over the handlebars.
sonatageek
09-26-09, 07:27 AM
I would add a set of interupter (cyclo-cross) levers to pare with the new aero levers. I have a neighbor with a nice old Miyata 210 who I am going to help do just such a set up. He likes the 'suicide' levers, and I told him there is a better and safer way.
http://www.sheldonbrown.com/images/interrupter-levers.jpg
photo from Sheldon Brown's web site.
I have some time (insomnia) so I'll give you some more instructions
i) optional, new brake levers: buy a pair of Tektro brake levers, they should cost you $20 or so. The modern 'aero' design, which has cables leaving parallel to the handlebars instead of in the arch you have now, provides slightly more mechanical advantage, which can lend itself to a better feeling brake.
1) first required step: new brake pads, for the front at least. Don't know for certain, but I think Koolstop Thinlines should do the trick. Make sure you get them with a threaded post. Install these so the front of the pad is a little closer to the rim than the back (called 'toe-in').
2) replace your cables and housing: The new fancy stuff with the plastic coating on the inside works great, and makes your brakes feel (and stop) much better. Make sure it's brake housing (you only make that mistake once, trust me). Make sure the housing has no major kinks, and no steep curves, all while being no longer than absolutly nessesary. It sounds harder than it is.
3) Adjust your brakes: easiest way to do this, that I've found.
a) loosen the barrel adjuster on top of the brake about 6 turns.
b) hold the brake calipers together (use a 3'rd hand tool, a toe strap, a friend, just about anything)
c) use a 4'th hand tool/ pliers to pull the cable down as tight as you can. Tighten the fixing bolt
d) loosen the barrel adjuster again, and be careful not to send yourself over the handlebars.
davidad
09-26-09, 03:33 PM
The shimano pads are the best in the wet or dry. Understand that the suicide levers are so named for a reason.
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