Brazing 990 mounts, over or under?

I'm getting ready to light the torch; I have built my brazing fixture
and have the 990 ("U-brake") bosses.

I think that, if all else were equal, I'd put them under the seat
stays as opposed to on top. Can anyone think of any reason not to do
that? As I recall, there was once a fad wherein they were mounted
under the chain stays behind the BB. It seems like the only issue I
heard was that they collected dirt quickly when mounted thus.

Jones

On Sep 18, 12:29 pm, !Jones wrote:
I'm getting ready to light the torch; I have built my brazing fixture
and have the 990 ("U-brake") bosses.

I think that, if all else were equal, I'd put them under the seat
stays as opposed to on top. Can anyone think of any reason not to do
that? As I recall, there was once a fad wherein they were mounted
under the chain stays behind the BB. It seems like the only issue I
heard was that they collected dirt quickly when mounted thus.

Jones

you should probably let whatever will give you best the routing
determine it

On Sep 18, 12:29 pm, !Jones wrote:
I'm getting ready to light the torch; I have built my brazing fixture
and have the 990 ("U-brake") bosses.

I think that, if all else were equal, I'd put them under the seat
stays as opposed to on top. Can anyone think of any reason not to do
that? As I recall, there was once a fad wherein they were mounted
under the chain stays behind the BB. It seems like the only issue I
heard was that they collected dirt quickly when mounted thus.

Jones

Make sure that your straddle cable clears. I can see it acting as a
wire saw on the seatstays.

forgive but i don't know a 900 from a ...
and off course a dirt deflector or two works if not stylish but who
notices?
the idea is factory design wise liability or high level comp or down
the rockies is the wheel rotation backs the assembly into the mount
not carrries the assembly away from the mount.

On Sep 18, 10:32 pm, datakoll wrote:
forgive but i don't know a 900 from a ...
and off course a dirt deflector or two works if not stylish but who
notices?
the idea is factory design wise liability or high level comp or down
the rockies is the wheel rotation backs the assembly into the mount
not carrries the assembly away from the mount.

pour some linseed in there after brazing or the tube will rust out.
allow drying, 3-4 weeks in warmth, then coat agin with walmart white
rusto gloss.

On Wed, 19 Sep 2007 02:32:37 -0000, in rec.bicycles.tech datakoll
wrote:

the idea is factory design wise liability or high level comp or down
the rockies is the wheel rotation backs the assembly into the mount
not carrries the assembly away from the mount.

I think you're putting your finger on the question... is there a
structural difference? I don't think that it makes any difference
which direction the wheel rotates, but I'm not sure. The under the
stay mount is cosmetic; I could put the bosses on either side.

Jones

It's hard to see how you would run the cable and housing with the, er,
brazed on center-pull, underneath the seat stays...

JG

On Sep 18, 9:54 pm, JG wrote:
It's hard to see how you would run the cable and housing with the, er,
brazed on center-pull, underneath the seat stays...

JG


this is by far the most common design used on current frames

On Tue, 18 Sep 2007 21:54:31 -0700, in rec.bicycles.tech JG
wrote:

It's hard to see how you would run the cable and housing with the, er,
brazed on center-pull, underneath the seat stays...

JG

Assume it's an... err... somewhat oddball frame and that the cable
routing will be fine if not better. Will there be any reason not to
do it that way that would go to the functionality of the brakes?

Jones

On Sep 18, 5:01 pm, Hank Wirtz wrote:
On Sep 18, 12:29 pm, !Jones wrote:

I'm getting ready to light the torch; I have built my brazing fixture
and have the 990 ("U-brake") bosses.

I think that, if all else were equal, I'd put them under the seat
stays as opposed to on top. Can anyone think of any reason not to do
that? As I recall, there was once a fad wherein they were mounted
under the chain stays behind the BB. It seems like the only issue I
heard was that they collected dirt quickly when mounted thus.

Jones

Make sure that your straddle cable clears. I can see it acting as a
wire saw on the seatstays.

An old Haro bmx frame I have runs a 990 on the chainstays. The cable
runs through a pierced seat tube.

The rationale on the BMX frame was for trick riding. Moving the brake
caliper south and out of the way lets you do certain tricks where your
foot wedges between frame and tire.

There were some old MTB frames that used this method. GT comes to
mind. Something about the brake being in a more advantageous position
for power, but it didn't seem like much more than a gimmick.

/s