Weak early 1980s Dia Compe sidepull brakes

[[email protected]]

I found an early 1980s Fuji Absolute road bike on the curb on trash day
and am restoring it. The rear brake is not working well. It has
aluminum Dia Compe sidepull brakes. Dia Compe levers with the safety
levers. There are no cable stops from the brake lever to the rear
brake. The brake housing extends in one piece from the brake lever to
the caliper. No stops. The cable and housing have been well greased
to reduce any friction.

When pulling on the rear brake lever the caliper will tighten somewhat
but will not spring open enough to keep from rubbing the rim. And the
brake lever will remain half compressed. The spring on the back of the
caliper does not appear to be strong enough to open the caliper arms
back up. The spring appears to be in the right spot. I have adjusted
the center pivot bolt so it is not too tight. The front brake is
identical but works OK. Of course it has about 3 feet less cable
housing.

Any suggestions? I have already thought of cheap Nashbar long reach
brakes for $30. The rims are 27" with 1.125" tires.

 

[Donald Gillies]

[email protected] writes:

>I found an early 1980s Fuji Absolute road bike on the curb on trash day
>and am restoring it. The rear brake is not working well.

>It has aluminum Dia Compe sidepull brakes. Dia Compe levers with the
>safety levers. There are no cable stops from the brake lever to the
>rear brake. The brake housing extends in one piece from the brake
>lever to the caliper. No stops. The cable and housing have been
>well greased to reduce any friction.

It would probably be good to take the caliper apart and make sure all
the bushings are clean, smooth and greased and to again make sure the
front acorn nut is not overtightened. You can compare the return
spring power on front brake and rear brake just by squeezing with your
hands if the wheels are removed.

>When pulling on the rear brake lever the caliper will tighten
>somewhat but will not spring open enough to keep from rubbing the
>rim. Any suggestions? I have already thought of cheap Nashbar long
>reach brakes for $30. The rims are 27" with 1.125" tires.

Another cheap solution is a new spring, $1.85 from
www.loosescrews.com, or from just about any local bike shop.

- Don Gillies
San Diego, CA

 

[Joshua Mermelstein]

Donald Gillies wrote:
> [email protected] writes:
>
>
>>I found an early 1980s Fuji Absolute road bike on the curb on trash day
>>and am restoring it. The rear brake is not working well.
>
>
>>It has aluminum Dia Compe sidepull brakes. Dia Compe levers with the
>>safety levers. There are no cable stops from the brake lever to the
>>rear brake. The brake housing extends in one piece from the brake
>>lever to the caliper. No stops. The cable and housing have been
>>well greased to reduce any friction.
>
>
> It would probably be good to take the caliper apart and make sure all
> the bushings are clean, smooth and greased and to again make sure the
> front acorn nut is not overtightened. You can compare the return
> spring power on front brake and rear brake just by squeezing with your
> hands if the wheels are removed.
>
>
>>When pulling on the rear brake lever the caliper will tighten
>>somewhat but will not spring open enough to keep from rubbing the
>>rim. Any suggestions? I have already thought of cheap Nashbar long
>>reach brakes for $30. The rims are 27" with 1.125" tires.
>
>
> Another cheap solution is a new spring, $1.85 from
> www.loosescrews.com, or from just about any local bike shop.
>
> - Don Gillies
> San Diego, CA
Good suggestions, but I had a bike in the early '80s with those brakes
and they were, on their best day, mediocre and most every other day, worse.

 

[Alex Rodriguez]

In article <[email protected]>,
[email protected] says...
>I found an early 1980s Fuji Absolute road bike on the curb on trash day
>and am restoring it. The rear brake is not working well. It has
>aluminum Dia Compe sidepull brakes. Dia Compe levers with the safety
>levers. There are no cable stops from the brake lever to the rear
>brake. The brake housing extends in one piece from the brake lever to
>the caliper. No stops. The cable and housing have been well greased
>to reduce any friction.
>When pulling on the rear brake lever the caliper will tighten somewhat
>but will not spring open enough to keep from rubbing the rim. And the
>brake lever will remain half compressed. The spring on the back of the
>caliper does not appear to be strong enough to open the caliper arms
>back up. The spring appears to be in the right spot. I have adjusted
>the center pivot bolt so it is not too tight. The front brake is
>identical but works OK. Of course it has about 3 feet less cable
>housing.
>Any suggestions? I have already thought of cheap Nashbar long reach
>brakes for $30. The rims are 27" with 1.125" tires.

Does the cable casing have a teflon liner? If not, even a well greased housing
can have enough drag to keep the brake spring from opening the caliper. I
would invest a few bucks on new housing that has a teflon liner.
---------------
Alex

 

[A Muzi]

[email protected] wrote:

> I found an early 1980s Fuji Absolute road bike on the curb on trash day
> and am restoring it. The rear brake is not working well. It has
> aluminum Dia Compe sidepull brakes. Dia Compe levers with the safety
> levers. There are no cable stops from the brake lever to the rear
> brake. The brake housing extends in one piece from the brake lever to
> the caliper. No stops. The cable and housing have been well greased
> to reduce any friction.
>
> When pulling on the rear brake lever the caliper will tighten somewhat
> but will not spring open enough to keep from rubbing the rim. And the
> brake lever will remain half compressed. The spring on the back of the
> caliper does not appear to be strong enough to open the caliper arms
> back up. The spring appears to be in the right spot. I have adjusted
> the center pivot bolt so it is not too tight. The front brake is
> identical but works OK. Of course it has about 3 feet less cable
> housing.
>
> Any suggestions? I have already thought of cheap Nashbar long reach
> brakes for $30. The rims are 27" with 1.125" tires.
>
You likely have a brake cable problem. Remove the brake
wire and look in the end of the casing. Is the aperture
round or oval? Is a bit of the steel casing occluding the
opening? Is there a kink near the end? That's common.
Kinked casing should be trimmed shorter behind the damaged
spot. Where the casing was bent the steel spiral is oval at
a spot. If you can't cut out the damaged parts, replace the
casing or get a complete cable.

With a smooth jawed plier remove any kinks in the wire or
replace it or get a complete cable.

Classic casing is plain steel . Modern brake cables use a
teflon lined casing and modern wires are smoother finished
too. In plain casing yes do grease the wire. If you have
teflon lined casing there isn't room for grease - it will
make your wire stick . Wipe the brake wire with oil inside
teflon casing.

When the wire is out, ensure the caliper returns smartly. If
not, get some oil along the centerbolt and between the arms
and between the inner arm and the spring holder and at the
end of the spring where it slides on the brake arm peg. Make
sure the caliper is properly adjusted so as to move freely
but not wiggle front to back nor bind all This paragraph's
work is easier to manage without the cable
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971