Replacing roller brakes with something else

Tim said:

I've got a hybrid bike made by Ridgeback fitted with Shimano Nexave
roller brakes front and rear, and the 7-speed Shimano hub. I've not
ridden this bike for a while, having bought a road bike, but now want
to cycle on some rougher tracks which the older bike is more suited
to. I'm finding the brakes on the hybrid bike to be next to useless
now though - I think this might have been one of the reasons I bought
the road bike. In the past I have replaced the front roller brake
unit, and have replaced the internal brake grease, but the braking is
just not strong enough for my liking. Would it be possible to ditch
the roller brake units and use good-quality dual-pivot brakes instead?

I strongly suggest replacing just the front brake and keeping the rear
roller brake. REAR rim brakes often don't work all that much better than
roller brakes and you don't need powerful braking at the back anyway*.
You'll also keep the advantages of low maintenance, low mess and zero rim
wear.

A front dual-pivot might be good if you can find one with enough clearance
for your tyres and mudguards. They're not great with fat tyres or
super-wide rims.

Quoted message said:

Would the bars currently used for the reflectors and mudguard mounts
above each wheel be suitable for this?

Are the forks drilled with the usual hole in the crown? Should be able to
use that.

Quoted message said:

Unfourtunatly there are no
mounting points for v-brakes or cantilevers.

Could perhaps get different forks. Also, how about a disc brake?

Quoted message said:

Would the removal of the
roller brake units leave gaps in the fork and rear frame that are too
wide for the wheels?

I think so, maybe spacers could be used. But you could simply leave the
roller brake in place and just not use it.

* http://www.sheldonbrown.com/brakturn.html

~PB

Pete Biggs said:

you don't need powerful braking at the back anyway*.

I don't know diddly about roller brakes but as for the difference
between front and rear brakes, I completely agree. I find I only ever
use my rear brake for slowing down (ie as opposed to stopping, and even
then I mostly use my front brake) or in conditions where I don't want to
risk losing front wheel traction (eg loose material on road surface). In
fact, this is exactly what I've taught my son - front brake for
stopping, rear brake for slowing down (eg when going down a slope).

Quoted message said:

A front dual-pivot might be good if you can find one with enough clearance
for your tyres and mudguards. They're not great with fat tyres or
super-wide rims.

At this point, I shall put in a recommendation for Alhonga deep-drop
DPs, £30 from SJS (which were in turn recommended to me by someone else
in this NG - might even have been yerself, Pete). I put them on my
'road' bike when I replaced the 27" wheels with 700C and they still have
plenty of drop to spare. And, most importantly, they seem to work well.
<URL:http://www.sjscycles.com/store/vIndex.htm?item79.htm>

d.

Why not just replace the front hub with a Sram hub brake which uses
traditional friction shoes much like in the rear brakes of most cars?
From what I have seen it would be more or less a straight swop, even
the torque reaction arm is very similar.

I would be reluctant to go the 'rim brake route'. These are fine for a
racing bike but are constantly dirtly, eat pads, wear rims and so on.

Regards,

Howard.

In message <[email hidden]>, Howard
<[email hidden]> writes

Quoted message said:

Why not just replace the front hub with a Sram hub brake which uses
traditional friction shoes much like in the rear brakes of most cars?
From what I have seen it would be more or less a straight swop, even
the torque reaction arm is very similar.

I would second that suggestion.

I have one on the front of my 'Utility' bike - it's been working fine
for years, needs little maintenance, and works very well. I use the bike
for towing the kiddie trailer and it never worries me that I don't have
good braking.

I have a roller brake on the rear, it's ok, but not as good as the old
coaster brake I had before. I have considered replacing it (probably
with Magura's) but as someone else has said rear braking power isn't as
crucial as long as you have a good front one.

Re. removing the rear roller. If it's like mine and my Nexus 7 speed,
the roller brake is actually a separate unit. My hub came with a metal
cap/spacer that you put in place of the roller unit.
--
Chris French, Leeds

Which roller brake are you using?
One option could be to try one of the IM70 roller brakes
which Shimano claim to be close to a mechanical disc.
www.shimano-europe.com/cycling/catalogue/content_prodx.phtml?pid=11022&psid=11010

Robin

Which roller brake are you using?
One option could be to try one of the IM70 roller brakes
which Shimano claim to be close to a mechanical disc.
www.shimano-europe.com/cycling/catalogue/content_prodx.phtml?pid=11022&psid=11010

Robin

[email hidden] (Robin Commander) wrote in message

Quoted message said:

One option could be to try one of the IM70 roller brakes
which Shimano claim to be close to a mechanical disc.
Robin

I would still go with the Sachs brake. The problem with the Shimano
one is that the hub itself contains an 'anti lock' device that slips
when the brake is fully applied. This would still operate even if a
more powerful roller brake were fitted.

I have toyed with the idea of drilling and pegging the hub on my Dutch
utility bike or otherwise modifying it to stop this anti-lock device
operating. This might be a dodgy thing to do though as perhaps the
roller brake by its nature locks up fully when applied hard, and so
would send you over the bars!

Howard said:

[email hidden] (Robin Commander) wrote in message

Quoted message said:

One option could be to try one of the IM70 roller brakes
which Shimano claim to be close to a mechanical disc.
Robin

I've got the IM50 version, so the IM70 may very well be more
powerful...

Quoted message said:

I would still go with the Sachs brake. The problem with the Shimano
one is that the hub itself contains an 'anti lock' device that slips
when the brake is fully applied. This would still operate even if a
more powerful roller brake were fitted.

I have toyed with the idea of drilling and pegging the hub on my Dutch
utility bike or otherwise modifying it to stop this anti-lock device
operating. This might be a dodgy thing to do though as perhaps the
roller brake by its nature locks up fully when applied hard, and so
would send you over the bars!

I have actually taken apart a Shimano power-modulator hub to try and
lock the anti-lock. The power-modulator inside the hub is a
multi-plate clutch, which slips at a given force. I removed the grease
from the clutch, and tightened it much more firmly than it was by
default, but it has not made much of a difference. Either the brake
just does not work very well, or I inadvertatly made the cluch slip
more easily. Maybe I could take it apart again and peg the plates
together to see if that helps.

I note that the instatllation notes for the Nexus version of the
roller brake now claim the unit is unsuitable for mountain bikes.
Whilst I don't have a mountain bike, I do live in Sheffield, and there
are many steep hills. When the bike was new, the braking effect was
pretty good, but now there is no "bite" at all - even after replacing
the roller brake unit, it was never as good as new.

I like the sound of the Sachs/SRAM brake. Presumably I'd need to get a
new wheel made with the new hub, and new brake levers? I might be nice
to re-fit the whole bike with SRAM kit, including a new hub gear for
the rear. Are the coaster brakes any good? But this could all get
rather expensive.

Tim

Hi Tim,

I think you could get away with just having the existing wheel rebuilt
(assuming it is of a good enough quality to make this worthwhile). I
would also think that you could use your existing lever and cables.
The hub costs about £50. I would leave the rear one as it is. Even
Record and Dura Ace use a less powerful brake on the rear!

Regards,

Howard.