brake measuring query

[manet]

i'm interested in putting stronger + better brakes on my ol'nova
for this year's deerfield gig. presently it wears old campy
sidepulls (they ain't short reach).

http://www.tektro.com/02products/index.php

where do i take the measurements to ascertain correct reach?




hey weisan, have you found a Ti kickstand?

[stevep]

center of the brake hole to ctr of the rim

steve sachs enterprises

[manet]

center of the brake hole to ctr of the rim

steve sachs enterprises

.

[Peter P.]

All else being equal, normal reach brakes SHOULD have more power than short reach because for a given cable pull, the pads would move more since the distance from the pivot is greater.

BUT, it also depends on the distance frome the centerbolt to cable clamp, perpendicular to the wheel plane. Since that can be changed by the manufacturer, there's no way of telling if swapping one brake for another will give greater braking force without using lab equipment to measure pressure at the pads versus force at the lever.

If you need more braking force than sidepulls, use cantilevers or V-brakes.

For what it's worth, I rode D2R2 in 2006 (115mi.)and 2005 (100km) and my V-brakes offered all the braking power I could ever ask for.

[Ken Robb]

Peter, I think you have your leverage ratios backwards. :confused: I have all kinds of brakes and none more powerful than DA 7800.

[RPS]

All else being equal, normal reach brakes SHOULD have more power than short reach because for a given cable pull, the pads would move more since the distance from the pivot is greater.

BUT, it also depends on the distance frome the centerbolt to cable clamp, perpendicular to the wheel plane. Since that can be changed by the manufacturer, there's no way of telling if swapping one brake for another will give greater braking force without using lab equipment to measure pressure at the pads versus force at the lever.

If you need more braking force than sidepulls, use cantilevers or V-brakes.

For what it's worth, I rode D2R2 in 2006 (115mi.)and 2005 (100km) and my V-brakes offered all the braking power I could ever ask for.When dealing with an existing frame, the distance from the mounting bolt to rim brake surface will be the same regardless of the range of adjustment of the brake pads -- hence the same whether long or short reach as long as it works.

Although measuring pressure as you suggest would be best because it accounts for friction, the same can be estimated by measuring the amount of cable travel versus pad movement. The less the pads move, the greater the clamping force will be, as is the case with dual pivot calipers versus single pivot.

[weisan]

hey weisan, have you found a Ti kickstand?

Yes, I did!

Look no further...it's right in the storeroom, on the other "dumpster" bike. Not Ti though, but weight-wennie it is...

http://alicehui.com/serotta/manet/kick_stevep_stand.jpg

Hey, listen to peter pan, for more breakin' power, you need this...I can take it off the "Kabuki" and send it over if you want...
http://alicehui.com/serotta/manet/brake_manet.jpg

btw, just prep the ti-bike for thingy1, whenever it arrives...
http://alicehui.com/serotta/manet/naked_thingy.jpg

Bet you haven't seen one of these...a threaded fork with a Star-Spangled....er..I mean star-fangled-nut.
http://alicehui.com/serotta/manet/threaded_star_fangled.jpg

okey...wife waiting...nite nite.