Disc brakes on tandems?

[email hidden] wrote in news:1108220511.546634.267190
@f14g2000cwb.googlegroups.com:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

2. What are some front fork options? 700C road tandem, rigid fork.

3. Anything else I should watch out for?

Thanks!

I suggest you read http://tandem-
fahren.de/Mitglieder/Christoph_Timm/DiskFAQ.html. Very few disc brakes
are rated for tandem use.

--
Mike DeMicco <[email hidden]>

Mike DeMicco said:

[email hidden] wrote in news:1108220511.546634.267190
@f14g2000cwb.googlegroups.com:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

2. What are some front fork options? 700C road tandem, rigid fork.

3. Anything else I should watch out for?

Thanks!

I suggest you read http://tandem-
fahren.de/Mitglieder/Christoph_Timm/DiskFAQ.html. Very few disc brakes
are rated for tandem use.

Thanks, great resource.
Anyone reading this use discs on a tandem?

"Mike DeMicco" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

[email hidden] wrote in news:1108220511.546634.267190
@f14g2000cwb.googlegroups.com:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

2. What are some front fork options? 700C road tandem, rigid fork.

3. Anything else I should watch out for?

Thanks!

I suggest you read http://tandem-
fahren.de/Mitglieder/Christoph_Timm/DiskFAQ.html. Very few disc brakes
are rated for tandem use.

You might want to have a look at
http://www.ne.jp/asahi/julesandjames/home/disk_and_quick_release/index.html

Just make sure you've big lawyers lips and very very tight quick releases.
Quite a few reports of wheels pulling out of mtb forks now. Industry still
got head in sand.

Russ

dianne_1234 said:

Thanks, great resource.
Anyone reading this use discs on a tandem?

I met a couple of tandemists a few years ago who were using Hope discs
as their only brakes. They were quite happy with them, although the
discs were clearly blued from heat. I'd go for the biggest and heaviest
rotor possible, for reasons of heat capacity rather than braking force.

Zog The Undeniable said:

dianne_1234 said:

Thanks, great resource.
Anyone reading this use discs on a tandem?

I met a couple of tandemists a few years ago who were using Hope discs
as their only brakes. They were quite happy with them, although the
discs were clearly blued from heat. I'd go for the biggest and heaviest
rotor possible, for reasons of heat capacity rather than braking force.

Heat is the main reason I'm looking for big rotors.

Anyone know which are the biggest rotors that will work with my Avid
cable actuated disc calipers?

Per [email hidden]:

Quoted message said:

3. Anything else I should watch out for?

From reading previous threads, I'd think about the ejection factor.

Seems tb almost-universally regarded as moot on a single given lawyer lips, but
I'd want to look into the implications for a tandem given the extra braking
effort...
--
PeteCresswell

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

2. What are some front fork options? 700C road tandem, rigid fork.

3. Anything else I should watch out for?

yes - my experience with avids was entirely unsatisfactory. very poor
modulation. avid were very nice on the phone & kept sending me new sets
of pads assuring me that they'd had a bad batch get into the supply
line, but 3 different sets of pads didn't make the slightest difference.
hopefully your experience is different, and i know hydraulic options
for road bikes are non-existent, but i recommend you try another bike
equipped with avids before committing.

Quoted message said:

Thanks!

(Pete Cresswell) said:

Per [email hidden]:

Quoted message said:

3. Anything else I should watch out for?

From reading previous threads, I'd think about the ejection factor.

not an issue if you use a hub with serrated axle faces, a decent closed
mechanism skewer like shimano and operate it in accordance with the
manufacturer's instructions.

the math showing ejection intentionally uses unrealistically low
assumptions about the force necessary to achieve axle slippage in an
effort to create a sensation - a sensation so sensational that not a
single lawyer has yet confessed to having gotten rich from chasing this
particular ambulance.

Quoted message said:

Seems tb almost-universally regarded as moot on a single given lawyer lips, but
I'd want to look into the implications for a tandem given the extra braking
effort...

[email hidden]:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

You actually asked 3 questions...

Quoted message said:

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

Avid only sells 160mm rotors for its road disc brake, but the adapter
used for 203mm rotors may be workable; email Avid for its opinion.

Quoted message said:

2. What are some front fork options? 700C road tandem, rigid fork.

Consider ordering a custom cyclocross fork with forward facing dropouts
(Wily Cycles is one manufacturer which does this). These are becoming
common, and quality and prices are quite comparable to well-known
"standard" forks.

Quoted message said:

3. Anything else I should watch out for?

Consider using a solid front axle with smooth-faced hexagonal nuts and
serrated washers between the nuts and forward-facing dropouts, to
decrease any worries with QR skewers and improper use of these.

Per jim beam:

Quoted message said:

yes - my experience with avids was entirely unsatisfactory. very poor
modulation. avid were very nice on the phone & kept sending me new sets
of pads assuring me that they'd had a bad batch get into the supply
line, but 3 different sets of pads didn't make the slightest difference.

I run an Avid on my rear wheel (160mm) and the modulation back there is ok for
what it's used for.

On my front wheel, however, I found an Avid mech on a 180mm rotor too grabby.
Thought it was just me or the pads or something....but you've confirmed my
decision to stick with a Hope C2 hydraulic up front.
--
PeteCresswell

(Pete Cresswell) said:

Per [email hidden]:

Quoted message said:

3. Anything else I should watch out for?

From reading previous threads, I'd think about the ejection factor.

Seems tb almost-universally regarded as moot on a single given lawyer lips, but
I'd want to look into the implications for a tandem given the extra braking
effort...

Yes, thanks for mentioning that. I'm actually worried a bit about the
disc force tending to eject the wheel.

A friend had movement in his disc-braked front wheel. He has a hybrid
bike with rigid fork and Avid mechanical discs, not unlike this one:
http://www.giantbicycles.com/us/030.000.000/030.000.000.asp?model=10807

He had just installed mudguards and couldn't figure why the front one
rubbed the tyre. After he installed the mudguards (mudguard and tyre
centred) he gave it a test ride. After he came to a stop the disc side
of the front axle had moved from the top of the slot to the lawyer
tabs, causing the tyre to rub the mudguard. We re-centred the wheel
and repeated the effect a few times. It was easily repeatable, and
easily observable.

His solution was to reverse the front skewer so the nut (with its
serrated steel ring) was on the disc side.

Even though he's fixed the problem (for now), I know what *might*
happen someday...

On Sun, 13 Feb 2005 08:46:17 -0800, jim beam <[email hidden]>

Quoted message said:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

2. What are some front fork options? 700C road tandem, rigid fork.

3. Anything else I should watch out for?

yes - my experience with avids was entirely unsatisfactory. very poor
modulation. avid were very nice on the phone & kept sending me new sets
of pads assuring me that they'd had a bad batch get into the supply
line, but 3 different sets of pads didn't make the slightest difference.
hopefully your experience is different, and i know hydraulic options
for road bikes are non-existent, but i recommend you try another bike
equipped with avids before committing.

Thanks for the feedback. I've already got the Avids, so it sounds like
I might be trying a few things -- or maybe switching back to rim
brakes... :-(

On Sun, 13 Feb 2005 08:54:22 -0800, jim beam <[email hidden]>

Quoted message said:

the math showing ejection

Right - can anyone re-calculate the maths with a typical tandem in
mind??

http://www.ne.jp/asahi/julesandjames/home/disk_and_quick_release/

Jose Rizal _@_._ said:

[email hidden]:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

You actually asked 3 questions...

Right, sorry! ;-)

Quoted message said:

Quoted message said:

1. What's the largest rotor size that will work with Avid cable
actuated "road" calipers? Will I need different caliper mounting
adapter plate(s)?

Avid only sells 160mm rotors for its road disc brake, but the adapter
used for 203mm rotors may be workable; email Avid for its opinion.

Thanks, that sounds like (potentially) good news; I was hoping
something like an existing bracket might work. I've emailed SRAM.

Quoted message said:

Quoted message said:

2. What are some front fork options? 700C road tandem, rigid fork.

Consider ordering a custom cyclocross fork with forward facing dropouts
(Wily Cycles is one manufacturer which does this). These are becoming
common, and quality and prices are quite comparable to well-known
"standard" forks.

Thanks, another promising lead. I've emailed Wily.

Quoted message said:

Quoted message said:

3. Anything else I should watch out for?

Consider using a solid front axle with smooth-faced hexagonal nuts and
serrated washers between the nuts and forward-facing dropouts, to
decrease any worries with QR skewers and improper use of these.

Good suggestion. I think a solid axle will go in my Deore HB-M525
hub...

Thanks for a very helpful post Jose!

jim beam said:

hopefully your experience is different, and i know hydraulic

options

Quoted message said:

for road bikes are non-existent,

Incorrect. Santana offers a cable-over-hydraulic system for road
tandems.

However, after seeing a rear disc overheat and warp into uselessness on
a tandem, forcing emergency repairs 20 miles into a 100mile ride, I'm
of the opinion that the only proper disc brakes for a tandem are rim
brakes. That's the biggest, meatiest "disc" brake you can put on a
bike.

Jeff

begin quoting <[email hidden]>:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

I'm curious to know why you don't want to use rim brakes and a drum brake.
--
David Damerell <[email hidden]> flcl?
Today is Second Monday, February.

David Damerell said:

Quoted message said:

Couple of questions for setting up disc brakes on our tandem.

Quoted message said:

I'm curious to know why you don't want to use rim brakes and a drum
brake.

Unless you've blown a tire off a rim from braking, the reason is less
apparent. Tandem tire blow-offs are well known. I have experienced
them on single bicycles as well and am aware of fatalities on local
descents that I am certain resulted from such an occurrence, there
being no other reasonable explanation for the crashes.

Jobst Brandt
[email hidden]

Per [email hidden]:

Quoted message said:

and am aware of fatalities on local
descents that I am certain resulted from such an occurrence, there
being no other reasonable explanation for the crashes.

That's an interesting observation.

When I lived on the island of Oahu a looooong time ago, one of the things that
struck me was that a cyclist was killed on something called the Likelike Pali
about once every month or so.

At the time I just figured it was a bad traffic mix.

But the descent into the town on either side of this sort-of-mountain is
*really* steep and long...Now I've got to wonder if people were losing front
tires on the descent.
--
PeteCresswell

Pete Cresswell said:

Quoted message said:

... and am aware of fatalities on local descents that I am certain
resulted from such an occurrence, there being no other reasonable
explanation for the crashes.

Quoted message said:

That's an interesting observation.

Quoted message said:

When I lived on the island of Oahu a looooong time ago, one of the
things that struck me was that a cyclist was killed on something
called the Likelike Pali about once every month or so.

Quoted message said:

At the time I just figured it was a bad traffic mix.

As I mentioned in this regard previously, there are a few major roads
in the Alps where bicycling downhill is prohibited for that reason.
An especially famous one is the Zirlerberg between Garmisch and
Innsbruck. It has six runaway exits for cars and trucks:

http://tinyurl.com/jhiu

Quoted message said:

But the descent into the town on either side of this
sort-of-mountain is *really* steep and long... Now I've got to
wonder if people were losing front tires on the descent.

The incidents here on Hicks and Metcalf roads were passed off as "too
much speed" something that anyone astute in accident reconstruction
could easily show that the tire blew off. If the rim has pavement
scrapes on its periphery it had no tire on it before the crash. The
report of the most recent Hicks road fatality had the condescending
tone toward an irresponsible bicyclist speeding out of control.

On the other hand, I don't want to see these roads closed to
bicyclists, only that riders are made aware of the hazard of
descending steep grades. I ride there on occasion and am careful to
distribute braking to both wheels and to not exceed 100psi inflation
pressure.

Jobst Brandt
[email hidden]