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Michael
July 9th 03, 11:23 PM
I've got threaded Delta Aztec brake pads in my Ultegra brakes on my
Cannondale road bike with (currently) Spinergy Spox wheels and
(previously) Mavic Open Pro/Ultegra wheelset.

The pads appear mounted correctly, in that the top of the pad meets
the top/outer diameter of the rim braking surface area exactly. But
the pads are about 2mm wider than the machined braking surface on the
wheels, meaning the bottom 2mm of pad doesn't contact the rim braking
surface.

So as the pads wear, a lip of un-worn-pad develops on the bottom of
the pad, and the lip rubs the inner/side portion of the rim. This has
worn away some of the stickers on the rim. I have to file down the
lip periodically.

Why would the pad be wider than the braking surface it mates with?
Does the lip contacting the inner portion of the rim during hard
braking present any problem? It seems like as the pad wears, the lip
would start contacting the rim before the rest of the pad, possibly
INSTEAD of the rest of the pad, dramatically decreasing braking power.

S. Anderson
July 10th 03, 02:27 AM
"Michael" > wrote in message
om...
> I've got threaded Delta Aztec brake pads in my Ultegra brakes on my
> Cannondale road bike with (currently) Spinergy Spox wheels and
> (previously) Mavic Open Pro/Ultegra wheelset.

<<snip..>>

> Why would the pad be wider than the braking surface it mates with?
> Does the lip contacting the inner portion of the rim during hard
> braking present any problem? It seems like as the pad wears, the lip
> would start contacting the rim before the rest of the pad, possibly
> INSTEAD of the rest of the pad, dramatically decreasing braking power.

Bicycle brakes are not exactly precision instruments. There are many
different types of rims, pads and brakes. The extra bit of brake pad
doesn't really matter. It won't affect braking performance significantly
but it will wear parts of the rim outside the intended braking area. Find
some narrower pads or make with the file. Your choice.

Cheers,

Scott..

Paul Southworth
July 10th 03, 05:45 PM
In article >,
Michael > wrote:
>I've got threaded Delta Aztec brake pads in my Ultegra brakes on my
>Cannondale road bike with (currently) Spinergy Spox wheels and
>(previously) Mavic Open Pro/Ultegra wheelset.
>
>The pads appear mounted correctly, in that the top of the pad meets
>the top/outer diameter of the rim braking surface area exactly. But
>the pads are about 2mm wider than the machined braking surface on the
>wheels, meaning the bottom 2mm of pad doesn't contact the rim braking
>surface.
>
>So as the pads wear, a lip of un-worn-pad develops on the bottom of
>the pad, and the lip rubs the inner/side portion of the rim. This has
>worn away some of the stickers on the rim. I have to file down the
>lip periodically.
>
>Why would the pad be wider than the braking surface it mates with?

Mfr apparently didn't anticipate how wide your braking surface
is.

>Does the lip contacting the inner portion of the rim during hard
>braking present any problem? It seems like as the pad wears, the lip
>would start contacting the rim before the rest of the pad, possibly
>INSTEAD of the rest of the pad, dramatically decreasing braking power.

No, when you clamp that brake lever, the lip will be crushed
and the face of the pad will meet the rim.

Consider removing the pads and trimming the bottom (the part
facing the ground) with a utility knife so that the pad is a little
narrower where it meets the rim.

--Paul

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