brake pad "toe" & grit embedding

[jim beam]

so, i've finally converted to the dark side, shimano, and have a
question about the brake toe orientation on their 7700 calipers.

both front & rear are toed slightly "forward", that is, the tip of the
pad to the front of the bike touches first. this is presumably for
modulation & squeal. but isn't it also the orientation to trap the
maximum amount of grit? is there any reason the toe can't be to the
rear so grit gets scuffed off /before/ getting trapped under the pad?

i'm thinking of rebuilding to swap the front & rear calipers to achieve
this "rear toe" effect, but has anyone else tried it? any reason /not/
to do it?

jb

 

[Zog The Undeniable]

jim beam wrote:

> so, i've finally converted to the dark side, shimano, and have a
> question about the brake toe orientation on their 7700 calipers.
>
> both front & rear are toed slightly "forward", that is, the tip of the
> pad to the front of the bike touches first. this is presumably for
> modulation & squeal. but isn't it also the orientation to trap the
> maximum amount of grit? is there any reason the toe can't be to the
> rear so grit gets scuffed off /before/ getting trapped under the pad?
>
> i'm thinking of rebuilding to swap the front & rear calipers to achieve
> this "rear toe" effect, but has anyone else tried it? any reason /not/
> to do it?

If you use rear toe, the back of the pad will be pulled forwards under
braking and the pad may judder badly (it depends on the rim surface)
with only the back making intermittent contact. Not a good idea, apart
from the grit thing.

 

[Richard Ney]

jim beam writes:

> both front & rear are toed slightly "forward", that is, the tip of the
> pad to the front of the bike touches first. this is presumably for
> modulation & squeal. but isn't it also the orientation to trap the
> maximum amount of grit?

I rub the rear (leading) edge of new pads on sand paper before
installing them to acheive the "toe-in". Grit's never been a problem
with the salmon colored Kool-Stop pads I use. I stopped using Shimano
pads when I saw how much they trapped grit and chewed up the aluminum
rims.

 

[Matt O'Toole]

Richard Ney wrote:

> jim beam writes:
>
>> both front & rear are toed slightly "forward", that is, the tip of
>> the pad to the front of the bike touches first. this is presumably
>> for modulation & squeal. but isn't it also the orientation to trap
>> the maximum amount of grit?
>
> I rub the rear (leading) edge of new pads on sand paper before
> installing them to acheive the "toe-in". Grit's never been a problem
> with the salmon colored Kool-Stop pads I use. I stopped using Shimano
> pads when I saw how much they trapped grit and chewed up the aluminum
> rims.

I agree. The problem is the crappy Shimano pads. Get some Kool-Stops and be
done with it.

Matt O.

 

[Qui si parla Campagnolo]

uce-<< both front & rear are toed slightly "forward", that is, the tip of the
pad to the front of the bike touches first. this is presumably for
modulation & squeal. but isn't it also the orientation to trap the
maximum amount of grit? >><BR><BR>

Don't matter cuz unless you bend the arm, you cannot change 'toe' of 7700
calipers. It took 7800 and how many eyars before shimano figured oiut how to
make the pads toe-able.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

 

[jim beam]

Qui si parla Campagnolo wrote:
> uce-<< both front & rear are toed slightly "forward", that is, the tip of the
> pad to the front of the bike touches first. this is presumably for
> modulation & squeal. but isn't it also the orientation to trap the
> maximum amount of grit? >><BR><BR>
>
> Don't matter cuz unless you bend the arm, you cannot change 'toe' of 7700
> calipers. It took 7800 and how many eyars before shimano figured oiut how to
> make the pads toe-able.

unless the toe is purely a function of the pad holders, if the forward
facing front toes to the front, and i swap the mounting bolts out
[pita], i should be end up with a rear brake toed to the rear. yes?

 

[Chris Zacho The Wheelman]

Some pads have a "wedged" portion in the back of them so most of the
grit is (supposively) scraped off. If you're worried, get one of these.
Personally, I've noticed no difference in grit gathering regardless of
toe-in.

- -

"May you have the wind at your back.
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner