Actual bike tech alert: New inner tube

[James]

http://www.bikebiz.com/news/read/production-to-start-on-schwalbe-s-thermoplastic-inner-tube/018702

I won't be rushing out to buy any.

--
JS

[cycl...@yahoo.com]

On Wednesday, November 18, 2015 at 12:37:42 PM UTC-8, James wrote:
> http://www.bikebiz.com/news/read/production-to-start-on-schwalbe-s-thermoplastic-inner-tube/018702
>
> I won't be rushing out to buy any.

Nice and light. This will help MTB's because they are so damned heavy. But what are the other attributes of these tubes? Are they more difficult to puncture? And on a road bike on a fast descent the TIRE can heat almost to the point that rim brakes heat the rims to.

Disks are a bad idea on street bikes because they have low rolling resistance and disks ALWAYS drag some.

I have just finished my Ridley Xbow and was trying it out yesterday. I hadn't set the cantilever return springs tight enough to not touch the VERY slight wobble in the front rim. So while in the shop it all worked perfect - out on the trail it touched slightly.

When I got home after just 20 miles I was about to collapse. I sat down and it took 20 minutes before I could do anything. So this almost negligible drag of the disk shoes isn't anything to sneer at. And while you can set road rim brakes to never touch you can't do this with a disk. If they can't do it on cars they sure as heck aren't going to go it on bicycles. Remember that the shoe is separate from the piston and the rolling vibration will always have it touching. This is why disk shoes wear so rapidly.

Now because of the way they are designed with disk brakes counter actuating on a solid surface vs. rim brakes actuating against a flexible rim, disk brakes have FAR superior stopping power if you don't melt aluminum disks into a puddle. But it will remain to be seen if the stopping power makes up for the increases rolling resistance.

[Doug Landau]

> Disks are a bad idea on street bikes because they have low rolling resistance

Disk brakes have rolling resistance?

[Joerg]

On 2015-11-18 14:15, cycl...@yahoo.com wrote:
> On Wednesday, November 18, 2015 at 12:37:42 PM UTC-8, James wrote:
>> http://www.bikebiz.com/news/read/production-to-start-on-schwalbe-s-thermoplastic-inner-tube/018702
>>
>>
>>
I won't be rushing out to buy any.
>

Same here :-)

> Nice and light. This will help MTB's because they are so damned
> heavy.

Heavy = better. Ever since I equipped my road bike with tube of 0.120"
wall thickness (about 3mm) there were no more flats. It's been over a
year now. On the MTB the tubes are a bit thicker, 0.160" or 4mm.


> ... But what are the other attributes of these tubes? Are they

> more difficult to puncture? And on a road bike on a fast descent the
> TIRE can heat almost to the point that rim brakes heat the rims to.
>
> Disks are a bad idea on street bikes because they have low rolling
> resistance and disks ALWAYS drag some.
>

What sort of disk brakes have you tried? Mine are Promax Decipher and
like many others they have U-shaped spring clips which keep the pads and
pistons away from the disk when not braking. When the calipers are
adjusted correctly there is no drag whatsoever. It's that silver
thingamagic in the picture:

http://www.promaxcomponents.com/wp-content/uploads/bfi_thumb/thumbnail52-m75iq9aeyarznlrwj6jvyteh590b1c96b2up4itsg0.jpg

In case Clive reads this: These low-end Promax hydraulic brakes are a
perfect example that bicycle gear can be made durable without Rolls
Royce pricing.

> I have just finished my Ridley Xbow and was trying it out yesterday.
> I hadn't set the cantilever return springs tight enough to not touch
> the VERY slight wobble in the front rim. So while in the shop it all
> worked perfect - out on the trail it touched slightly.
>
> When I got home after just 20 miles I was about to collapse. I sat
> down and it took 20 minutes before I could do anything. So this
> almost negligible drag of the disk shoes isn't anything to sneer at.
> And while you can set road rim brakes to never touch you can't do
> this with a disk. If they can't do it on cars they sure as heck
> aren't going to go it on bicycles. Remember that the shoe is separate
> from the piston and the rolling vibration will always have it
> touching. This is why disk shoes wear so rapidly.
>

Huh? The brake pads on my car are barely half worn down and its been
77000 miles now. On cars they do drag a little (very little) but
generally not on bicycle disk brakes.

> Now because of the way they are designed with disk brakes counter
> actuating on a solid surface vs. rim brakes actuating against a
> flexible rim, disk brakes have FAR superior stopping power if you
> don't melt aluminum disks into a puddle.

Ummm ... they are made from steel.


> ... But it will remain to be

> seen if the stopping power makes up for the increases rolling
> resistance.
>

What rolling resistance? The only time I feel any on my MTB is when
those dreaded holes in the disks have caught enough vegetation and the
poker of the Swiss Army knife has to come out for a trailside cleaning job.

--
Regards, Joerg

http://www.analogconsultants.com/

[John B.]

But don't worry as the original poster stipulated that they have "low"
rolling resistance :-)
--

Cheers,

John B.

[Ralph Barone]

James <james.e...@gmail.com> wrote:
> http://www.bikebiz.com/news/read/production-to-start-on-schwalbe-s-thermoplastic-inner-tube/018702
>
> I won't be rushing out to buy any.
>

"Not available for bikes with rim brakes". Because the heat from rim
brakes could melt it? That doesn't sound like a step forwards.

[Frank Krygowski]

On 11/19/2015 9:31 PM, Phil W Lee wrote:
> Doug Landau <doug....@gmail.com> considered Wed, 18 Nov 2015

> 14:36:45 -0800 (PST) the perfect time to write:
>
>>
>>> Disks are a bad idea on street bikes because they have low rolling resistance
>>
>> Disk brakes have rolling resistance?
>>

> In use, yes.
> It's kinda the point :)
>
> There's no reason that a properly aligned and adjusted disk caliper
> should drag any more than a properly aligned and adjusted rim caliper
> when released.

I've never owned a disk brake bike, but I've ridden several that
belonged to others. Some definitely made scraping sounds with the brake
off. One tourist who had ridden 60 miles that day to get to my house
assured me that the scraping was "normal."

I can't say how much drag it imposed; my ride was a short one, testing
an unrelated repair I made for him. But I know the scraping would have
driven me nuts.


--
- Frank Krygowski

[Clive George]

Knobblies hide the sound :-)

Ours sometimes seem to scrape - but spinning the wheel shows it's not
actually dragging. I think the scraping goes away after a short while
anyway - I certainly don't remember being bothered by it.

[avag...@gmail.com]

UCI UCI ?

If ura PIG in TSD ...

gotta be a LARGE problem investing. $$$$$ only to wait on a 'deliberative body'

shit...my Redline XC on Schwinebees is so heavy it doesn't fall off a cliff.

Poly hulled kayaks are HEAVY but wear and impact fracture tolerant...flex not Crac
yet no horn blowing here...nada

Cheap compared with glass...no hand work..19 pounds ?

19 POUNDS ?

will UCI yield ?

[John B.]

On Fri, 20 Nov 2015 02:31:32 +0000, Phil W Lee <ph...@lee-family.me.uk>

wrote:

>Doug Landau <doug....@gmail.com> considered Wed, 18 Nov 2015
>14:36:45 -0800 (PST) the perfect time to write:
>
>>

>>> Disks are a bad idea on street bikes because they have low rolling resistance
>>
>>Disk brakes have rolling resistance?
>>

>In use, yes.
>It's kinda the point :)
>
>There's no reason that a properly aligned and adjusted disk caliper
>should drag any more than a properly aligned and adjusted rim caliper
>when released.

I can only comment on the one disk brake that I've actually,
personally, examined and it certainly "dragged", or at lest made a
rubbing noise when you rode the bike. The owner said that it had,
"always done that."
--

Cheers,

John B.

[David Scheidt]

John B. <sloc...@gmail.com> wrote:
:On Fri, 20 Nov 2015 02:31:32 +0000, Phil W Lee <ph...@lee-family.me.uk>

It shouldn't. But there are lots of bad mechanics who can't set up a
disk brake, same as there are mechanics who can't set up cantis.

If the disk rubs, the caliper is on wrong, or the disk si bent. Som
brakes are more difficult to get perfect than others, and crappy ones
probably aren't wroth the trouble.


--
sig 15

[Sir Ridesalot]

A friend of mine had a $1500.00 Davinci MTB with disc brakes that wore out the pads so quickly and that three different bike shops couldn't get to work right that he traded the wheels for ones that had brake tracks and he converted his bike to V-brakes. Then he was a very happy bicyclist.

Cheers

[cycl...@yahoo.com]

On Wednesday, November 18, 2015 at 2:36:47 PM UTC-8, Doug Landau wrote:
> > Disks are a bad idea on street bikes because they have low rolling resistance
>
> Disk brakes have rolling resistance?

Doug - this is a tech group. I expect you not to be thick. A street bike is supposed to have a very low rolling resistance. Is that something you didn't know?

[cycl...@yahoo.com]

You must live in an area of good roads. Here it doesn't matter if the tubes are thick or thin - you get flats unless you use Gatorskins or Armadillos. since you have to use heavy tires you want to use lighter innertubes to give you an easier time.

The clips on the disk brake don't work particular well - just spin the wheel and watch how rapidly it slows. Most stop at about twice the rate of a road wheel. (Yeah, I know - some of this is from the drag of the seals on the sealed bearings.) This is because mechanical or hydraulic you have to set them in very close because the mechanical advantage has to be very high on the mechanism. Being this close causes enough touching from vibration to add additional rolling resistance.

Because of disk brakes on cars being "power driven" they can be set further away from the disks using a lower mechanical advantage. Also car disks are much larger and much thicker. And so because of the added material they are much longer wearing despite pad wear. Remember that all of the weight of the vehicle has to be dissipated somehow. The friction between the disk and the pad MUST wear the pads down.

I don't know if you remember that kitchen knives would be sharpened on a steel sharpener and they would wear down just with the wear against the very slight steel edge of a kitchen knife. One of my father's first jobs was working in a restaurant and one of his jobs was to sharpen all the knives first thing getting to work. He was so fast at sharpening that the knives would be too hot to touch for a minute or so.

The latest thing in disks is aluminum for racing since they are lighter and have better heat conduction. They now have cooling fins on them. But you are advised that you COULD melt them.

[cycl...@yahoo.com]

Mine doesn't make a scrapping sound but you can tell that there's excess drag. And the noise may go away because of wear on the pads making them fit the surfaces better. It isn't unusual for me to outrun much younger guys up the hills on my cross bike with rim brakes. Yes there's a sizable weight difference but there's also a sizable age difference.

[cycl...@yahoo.com]

David, this has nothing whatsoever to do with the skill of the mechanic. It has everything to do with an extremely high mechanical advantage forcing very close clearances and the minor movement of the pads on their clips when released.

[John B.]

On Fri, 20 Nov 2015 13:43:05 +0000 (UTC), David Scheidt
<dsch...@panix.com> wrote:

>John B. <sloc...@gmail.com> wrote:
>:On Fri, 20 Nov 2015 02:31:32 +0000, Phil W Lee <ph...@lee-family.me.uk>
>:wrote:
>
>:>Doug Landau <doug....@gmail.com> considered Wed, 18 Nov 2015
>:>14:36:45 -0800 (PST) the perfect time to write:
>:>
>:>>
>:>>> Disks are a bad idea on street bikes because they have low rolling resistance
>:>>
>:>>Disk brakes have rolling resistance?
>:>>
>:>In use, yes.
>:>It's kinda the point :)
>:>
>:>There's no reason that a properly aligned and adjusted disk caliper
>:>should drag any more than a properly aligned and adjusted rim caliper
>:>when released.
>
>:I can only comment on the one disk brake that I've actually,
>:personally, examined and it certainly "dragged", or at lest made a
>:rubbing noise when you rode the bike. The owner said that it had,
>:"always done that."
>
>It shouldn't. But there are lots of bad mechanics who can't set up a
>disk brake, same as there are mechanics who can't set up cantis.
>

You apparently have a rather strange definition for "bicycle
mechanic".

>If the disk rubs, the caliper is on wrong, or the disk si bent. Som
>brakes are more difficult to get perfect than others, and crappy ones
>probably aren't wroth the trouble.
--

Cheers,

John B.

[jbeattie]

Hmmm. Rolling resistance refers to the rolling friction or rolling drag of the tire against the ground. It has nothing to do with disc brakes.

I've been riding with mechanical discs for close to ten years on my commuter bike, and I hadn't noticed any additional wheel drag -- until I added a dyno hub. By wheel drag, I mean when I spin the wheel, it seems to keep turning like any other non-disc wheel. I can't comment on whether there is additional aerodynamic drag on the bike as a whole -- and of course, this assumes the brakes are properly adjusted, and the pads are not dragging on the disc.

-- Jay Beattie.

[avag...@gmail.com]

Andy, is The Jersey testing aerofoam tubes for potential sales ?

[sms]

I have mechanical discs on one bike in the fleet. Of course there is no
extra rolling resistance. Unless the poster was referring to the
additional mass of the disc that is present on the wheel versus using
the rim surface for braking.

I have a wheel with an Arai drum brake for our tandem. I rarely use it.
I thought we would do some loaded touring on the tandem where it would
be necessary but that never happened. The one tour I did with it was in
Russia where we had a sag wagon that carried our gear and the vodka.

[David Scheidt]

John B. <sloc...@gmail.com> wrote:
:On Fri, 20 Nov 2015 13:43:05 +0000 (UTC), David Scheidt

:<dsch...@panix.com> wrote:

:>John B. <sloc...@gmail.com> wrote:
:>:On Fri, 20 Nov 2015 02:31:32 +0000, Phil W Lee <ph...@lee-family.me.uk>
:>:wrote:
:>
:>:>Doug Landau <doug....@gmail.com> considered Wed, 18 Nov 2015
:>:>14:36:45 -0800 (PST) the perfect time to write:
:>:>
:>:>>
:>:>>> Disks are a bad idea on street bikes because they have low rolling resistance
:>:>>
:>:>>Disk brakes have rolling resistance?
:>:>>
:>:>In use, yes.
:>:>It's kinda the point :)
:>:>
:>:>There's no reason that a properly aligned and adjusted disk caliper
:>:>should drag any more than a properly aligned and adjusted rim caliper
:>:>when released.
:>
:>:I can only comment on the one disk brake that I've actually,
:>:personally, examined and it certainly "dragged", or at lest made a
:>:rubbing noise when you rode the bike. The owner said that it had,
:>:"always done that."
:>
:>It shouldn't. But there are lots of bad mechanics who can't set up a
:>disk brake, same as there are mechanics who can't set up cantis.
:>

:You apparently have a rather strange definition for "bicycle
:mechanic".

Someone employed to work on bikes is a strange definition? Sadly,
there's no requirement for compentency.


--
sig 42

[John B.]

On Sat, 21 Nov 2015 04:28:06 +0000 (UTC), David Scheidt

Well, within the trades, "mechanic" usually has a rather specific
meaning, normally regarding competence :-)
--

Cheers,

John B.

[AMuzi]

You're right in principle ( well, mostly. Getting a
sharpened edge overly hot isn't best practice but that
depends on how hot is hot I suppose).

In practice, a good many disc brakes on bicycles arrive here
not properly centered and so tightening or loosening the
brake adjustment results in either drag or poor response or
both. That can be done well even on cheaper models; there
really aren't 'junk' disc brakes even on XMart models. They
are a simple design, hard to screw up, but assembly rigor is
frequently lacking.

Out-of-plane discs (poorly manufactured, damaged, improperly
mounted) are another common problem which simple user
adjustments will not resolve.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

[Frank Krygowski]

I wish that were so! But IME, mechanics (like machinists, like
electrical engineers, like physicians, etc. etc.) all have their
individual limits on competence.

I found out the hard way that an auto mechanic could be excellent at
timing belt work, alternator work, and so on; but incompetent enough on
AC to destroy an air conditioning compressor. :-(


--
- Frank Krygowski

[Joerg]

I have Gatorskins on my road bike but in the beginning I still got flats
because those have flimsy sidewalls. Then I bought tubes with 0.120" or
3mm wall thickness all around. That fixed it. Zero flats in more than a
year.

> The clips on the disk brake don't work particular well - just spin
> the wheel and watch how rapidly it slows. Most stop at about twice

> the rate of a road wheel. ...


Well, mine don't.


> ... (Yeah, I know - some of this is from the

> drag of the seals on the sealed bearings.) This is because mechanical
> or hydraulic you have to set them in very close because the
> mechanical advantage has to be very high on the mechanism. Being this
> close causes enough touching from vibration to add additional rolling
> resistance.
>

Good bicycle brakes don't touch the disk. The caliper pistons should
visibly release and mine do so. The springs make sure that the pads are
snug on the pistons. It has to be that way because disks are never 100%
wobble-free and you'd otherwise always hear "phhh..ching ... phhh..ching".

> Because of disk brakes on cars being "power driven" they can be set
> further away from the disks using a lower mechanical advantage. Also
> car disks are much larger and much thicker. And so because of the
> added material they are much longer wearing despite pad wear.
> Remember that all of the weight of the vehicle has to be dissipated
> somehow. The friction between the disk and the pad MUST wear the pads
> down.
>

Sure, they have to be accordingly bigger.

> I don't know if you remember that kitchen knives would be sharpened
> on a steel sharpener and they would wear down just with the wear
> against the very slight steel edge of a kitchen knife. One of my
> father's first jobs was working in a restaurant and one of his jobs
> was to sharpen all the knives first thing getting to work. He was so
> fast at sharpening that the knives would be too hot to touch for a
> minute or so.
>

Probably he had the muscle for the fast motion that requires. We still
use a steel sharpener.

> The latest thing in disks is aluminum for racing since they are
> lighter and have better heat conduction. They now have cooling fins
> on them. But you are advised that you COULD melt them.
>

I would never use aluminum for a safety-critical part like that.

[Sir Ridesalot]

A lot of big bicycles shops in Toronto, Canada use "Bicycle Assemblers" during their busy season. The "Bicycle Assembler" assembles the bicycle and hopefully a "Bicycle Mechanic" checks it before it's sold.

Shops hire and pay the "Bicycle Assemblers" less than they pay the mechanics.

Cheers

[sms]

Why are you even responding? No one's bicycle disc brakes do this. In
fact, due to the mass of the disk they actually will spin a little longer.

[Joerg]

On 2015-11-21 12:02, sms wrote:
> On 11/21/2015 11:43 AM, Joerg wrote:
>> On 2015-11-20 16:00, cycl...@yahoo.com wrote:

[...]

>>
>>> The clips on the disk brake don't work particular well - just spin
>>> the wheel and watch how rapidly it slows. Most stop at about twice
>>> the rate of a road wheel. ...
>>
>>
>> Well, mine don't.
>
> Why are you even responding? No one's bicycle disc brakes do this. In
> fact, due to the mass of the disk they actually will spin a little longer.
>

But the knobbies on the tires present more air disturbance and slow it
down :-)

[Duane]

Picking a good LBS can solve this problem. Though I think in Montreal
it's mostly the box stores and maybe MEC that do this.

--
duane

[Sir Ridesalot]

On Saturday, November 21, 2015 at 3:30:17 PM UTC-5, Duane wrote:
> Sir Ridesalot <i_am_cyc...@yahoo.ca> wrote:
Snipped

> > A lot of big bicycles shops in Toronto, Canada use "Bicycle Assemblers"
> > during their busy season. The "Bicycle Assembler" assembles the bicycle
> > and hopefully a "Bicycle Mechanic" checks it before it's sold.
> >
> > Shops hire and pay the "Bicycle Assemblers" less than they pay the mechanics.
> >
> > Cheers
> >
>
> Picking a good LBS can solve this problem. Though I think in Montreal
> it's mostly the box stores and maybe MEC that do this.
>
> --
> duane

Many years ago I worked at BLOOR CYCLE in Toronto, Canada and that's what they did. Second floor was the domain of the "Bicycle Assemblers" and the ground/main floor was the repair area - domain of the mechanics and the sales floor. The mechanics checked every bicycle before it went out the door with a customer. there was no problem with that system as it freed up the mechanics' time to do actual repairs. Bloor Cycles was a VERY Reputable shop.

Cheers

[Duane]

There you go. Not all are reputable. So I try to support the ones that
are reputable even if they're not the cheapest.

--
duane

[Sir Ridesalot]

DITTO! +10.

Cheers

[Ralph Barone]

<cycl...@yahoo.com> wrote:

> Jay, I expect you as well to actually read something before you write. A
> street bike is supposed to have low rolling resistance. ANYTHING that
> adds friction through any medium reduces that rolling resistance.
>
> On a heavy full suspension bike with knobbies, the additional friction of
> a dragging disk doesn't add much in comparison to all of the other drags
> but on a street bike designed for minimum AIR resistance, tire rolling
> resistance and every other source of resistance at a bare minimum, the
> addition of a slight disk drag is quite pronounced.
>
> Have you even ridden a disk bike?
>

I wanna see the reply to this...

[avag...@gmail.com]

more pressure in the gatorskins esp at the rear.

[James]

On 22/11/15 07:14, cycl...@yahoo.com wrote:
> On Friday, November 20, 2015 at 4:59:03 PM UTC-8, jbeattie wrote:

> Jay, I expect you as well to actually read something before you
> write. A street bike is supposed to have low rolling resistance.
> ANYTHING that adds friction through any medium reduces that rolling
> resistance.
>
> On a heavy full suspension bike with knobbies, the additional
> friction of a dragging disk doesn't add much in comparison to all of
> the other drags but on a street bike designed for minimum AIR
> resistance, tire rolling resistance and every other source of
> resistance at a bare minimum, the addition of a slight disk drag is
> quite pronounced.
>
> Have you even ridden a disk bike?
>

I have a mid price range aluminium framed MTB with mechanical disk
brakes. I put cheap 40mm slicks on it a while back. I can put the bike
on a stand and spin the wheels, and they don't seem to slow quickly as
you might expect from a dragging brake, yet it still rides like a pig
compared to my road bike.

--
JS

[Frank Krygowski]

On 11/21/2015 10:26 PM, James wrote:
>
> I have a mid price range aluminium framed MTB with mechanical disk
> brakes. I put cheap 40mm slicks on it a while back. I can put the bike
> on a stand and spin the wheels, and they don't seem to slow quickly as
> you might expect from a dragging brake, yet it still rides like a pig
> compared to my road bike.

Hmm. Well, if the disk is dragging, I think you'd hear it anyway.

I'd bet the main differences would be the tires.

Another factor would be the much less aero profile of a rider on a MTB.
Standard horizontal handlebars (as opposed to drop bars) tend to put
your elbows out beyond the sides of your torso. The difference in
frontal area and thus areo drag is significant.

--
- Frank Krygowski

[John B.]

Certainly, but as I said, "within the trades". If you go out looking
for a job on an off shore rig as a mechanic you probably won't get
hired... unless someone knows you and confirms your abilities.

Had you come to my old company looking for a position as an "Engineer"
we would read all about your history with the PE and all and the
collage lecturing and then ask you, "Who have you worked for"?

And if you seemed all right we'd certainly contact the people that you
had worked for to see if you actually "were all right".

>I found out the hard way that an auto mechanic could be excellent at
>timing belt work, alternator work, and so on; but incompetent enough on
>AC to destroy an air conditioning compressor. :-(

That is two different areas of expertise :-)
--

Cheers,

John B.

[John B.]

And probably hade a very good reputation in the community and as a
result it was likely a pretty successful business.
--

Cheers,

John B.

[Andrew Chaplin]

Sir Ridesalot <i_am_cyc...@yahoo.ca> wrote in
news:4e62d14f-d86b-450d...@googlegroups.com:

> A lot of big bicycles shops in Toronto, Canada use "Bicycle Assemblers"
> during their busy season. The "Bicycle Assembler" assembles the bicycle
> and hopefully a "Bicycle Mechanic" checks it before it's sold.

I was an assembler in Ottawa in the 1970s.

> Shops hire and pay the "Bicycle Assemblers" less than they pay the
> mechanics.

That they did.
--
Andrew Chaplin
SIT MIHI GLADIUS SICUT SANCTO MARTINO
(If you're going to e-mail me, you'll have to get "yourfinger." out.)

[Andrew Chaplin]

Sir Ridesalot <i_am_cyc...@yahoo.ca> wrote in

news:4c0bcb5b-54f3-4ab5...@googlegroups.com:

> Many years ago I worked at BLOOR CYCLE in Toronto, Canada and that's
> what they did. Second floor was the domain of the "Bicycle Assemblers"
> and the ground/main floor was the repair area - domain of the mechanics
> and the sales floor. The mechanics checked every bicycle before it went
> out the door with a customer. there was no problem with that system as
> it freed up the mechanics' time to do actual repairs. Bloor Cycles was
> a VERY Reputable shop.

Even in Ottawa in the early 1970s, Bloor Cycle had a decent reputation.

[Frank Krygowski]

Right. Unfortunately he didn't realize that, and told me he could fix
the AC.

--
- Frank Krygowski

[jbeattie]

Oddly enough, Tom's post doesn't show up in the thread, except in your post. Maybe that's a Google Group thing.

And for Tom, I expect you, too, to read before posting -- and bathe, pay your taxes and eat your vegetables. Note the section of my post stating that I've been riding a mechanical disc-equipped bike to work for about the last ten years (not quite). My non-dyno front wheels spin like champs. No brake drag whatsoever. Who knows what sort of aerodynamic drag the caliper/disc might add. I podium every morning on my commute to work, so its not holding me back too much. And the discs are great in wet weather, which I will see a lot for the next seven months. Another advantage is that I don't get a leaf-pile built up around a rim-brake caliper and grind down the rim brake track with road grit.


My only current criticism of discs is that my rear disc is feeling flaccid at the lever and doesn't generate much braking force. I have to play with that today -- but its dry, and I'm going out on my fast bike first.

-- Jay Beattie.

[David Scheidt]

John B. <sloc...@gmail.com> wrote:
:On Sat, 21 Nov 2015 11:25:02 -0500, Frank Krygowski

Bike shops in the US pay shit. (When I was running an auto shop, I hired
the best mechanic away from a local bike store. I was paying him more as
they were, and his job for me was clean the floors, and general dogsbody.
Their posted shop rate was higher than ours...). Given that, many have
to settle for less than fully competent employees.

--
sig 27

[sms]

On 11/22/2015 8:24 AM, jbeattie wrote:

<snip>

> My only current criticism of discs is that my rear disc is feeling flaccid at the lever and doesn't generate much braking force. I have to play with that today -- but its dry, and I'm going out on my fast bike first.

I was out on my mountain bike today, which has mechanical discs, and
there is no drag.

Maybe the misconception he has comes from automotive hydraulic disc
brakes where the pad always lightly contacts the rotor. On a properly
set-up bicycle hydraulic disc brake, with un-warped rotors, this should
not occur.

[John B.]

On Sun, 22 Nov 2015 10:22:40 -0500, Frank Krygowski

Well, as they say, there are two methods of learning about something.
Read the manual, or just go ahead and have at it. The latter is
usually the most expensive :-)
--

Cheers,

John B.

[John B.]

On Sun, 22 Nov 2015 17:32:51 +0000 (UTC), David Scheidt

It has been some years now since I was in the States but the usual
norm is that you get just what you pay for.
--

Cheers,

John B.

[Sir Ridesalot]

On Monday, November 23, 2015 at 6:06:35 AM UTC-5, John B. wrote:
Snipped

> Well, as they say, there are two methods of learning about something.
> Read the manual, or just go ahead and have at it. The latter is
> usually the most expensive :-)
> --
>
> Cheers,
>
> John B.

LINDBERG Plastic models used to include on the instruction sheet a cartoon of a guy tearing out his hair. Under that was the admonition, "When all else fail read the instructions".
then again I can't understand the number of people who can't/won't follow even simple instructions.

I have people come to me with what should be a simple bicycle problem. I troubleshoot it and tell them what to do to correct it. Many times they ignore it and keep riding. Then tthey suffer a major failure like a collapsed wheel because they didn't get spokes replaced or tightened. One guy took apart a bunch of used cassettes to make up a custom cluster. I tod him he'd get chain skip because a lot of the cogs were badly worn as was the chain. Sure enough a few days later he's here complaining about the chain skipping when he puts pressure on the pedals but it doesn't happen i n all the gears. Duh, how do you help someone who refuses to follow simple instructions?

Cheers

[avag...@gmail.com]

no bike disc here but 4 huge discs on muh van equipped with a steel cargo partition.

I'm taken aback by the beef...like brake front wheel drag ? does your changard rattle ?

apologies to the Canadians.

[sms]

On 11/21/2015 3:09 PM, Duane wrote:

> There you go. Not all are reputable. So I try to support the ones that
> are reputable even if they're not the cheapest.

Tough to find the reputable shops for a lot of people.

One source that's good, but only available in a couple of areas, is
Consumer Checkbook, a non-profit that collects ratings of stores of all
kinds. <http://www.checkbook.org/>.

I searched for shops in my area that were within 10 miles and top rated
for service both in quality and price. 2 shops resulted (out of 22
total). One was the very famous Slough's in downtown San Jose.

When I removed price from the search, there were 7 results, one of which
was REI and one of which was Performance.

[Duane]

We have Consumer references here in Montreal but I find it more useful
to talk to other cyclists, particularly ones that use the same type of
equipment that I do.

[sms]

LOL. It would be great to know why the other poster believes that disc
brakes on bicycles add drag.

Mechanical disk brakes have springs that retract the pads from the
rotor. Hydraulic disks retract the pads far enough that there should be
no friction if the rotor is not warped.

I suspect that his confusion stems from automobile disc brakes where the
pads could barely contact the rotor.

But maybe, since he used "disk" rather than "disc" the misunderstand
relates to something else, related to computers. "Disk is the standard
spelling for computer-related terms such as hard disk and floppy disk.
Disc is the standard spelling for phonograph records, albums (in the
figurative sense—a group of songs presented in sequence), and components
of plows and brake systems."

In any case, it's great to see disc brakes finally appearing on road
bikes. When you're descending a twisty mountain road it's very nice to
have disc brakes. There's a few roads in the Bay Area where I would stop
partway down to let the rims cool.

[Doug Landau]

> But maybe, since he used "disk" rather than "disc" the misunderstand
> relates to something else, related to computers. "Disk is the standard
> spelling for computer-related terms such as hard disk and floppy disk.
> Disc is the standard spelling for phonograph records, albums (in the

> figurative sense--a group of songs presented in sequence), and components

> of plows and brake systems."

Oh, nonsense.

[jbeattie]

Slough's is now very famous? I used to buy stuff from George out of his house in Almaden Valley -- which was kind of like an episode of Hoarders but with bike stuff. http://www.mylifetime.com/shows/Hoarders Go pick a derailleur out of the sink. He had a hall closet with bike clothes in it -- the source of many of my scratchy Sergal/Moa jerseys and some early, not scratchy Kuchariks.

His day job was managing a science lab at SJSU (or something of the sort), so sometimes I'd go over to campus and pick things up. He had everything -- and incredible deals on Campy. He was underground parts pimp for those in the know.

The local shops ganged up on him (prominently Terry Shaw) and exerted pressure through Mike Sinyard at the still-small Specialized who threatened to cut-off his Campy parts supply if he didn't get a bricks-and-mortar store. And thus Slough's Bike Shoppe was born.

-- Jay Beattie.

[sms]

On 11/23/2015 1:46 PM, jbeattie wrote:
> On Monday, November 23, 2015 at 10:02:10 AM UTC-8, sms wrote:

<snip>

> Slough's is now very famous? I used to buy stuff from George out of his house in Almaden Valley -- which was kind of like an episode of Hoarders but with bike stuff. http://www.mylifetime.com/shows/Hoarders Go pick a derailleur out of the sink. He had a hall closet with bike clothes in it -- the source of many of my scratchy Sergal/Moa jerseys and some early, not scratchy Kuchariks.
>
> His day job was managing a science lab at SJSU (or something of the sort), so sometimes I'd go over to campus and pick things up. He had everything -- and incredible deals on Campy. He was underground parts pimp for those in the know.
>
> The local shops ganged up on him (prominently Terry Shaw) and exerted pressure through Mike Sinyard at the still-small Specialized who threatened to cut-off his Campy parts supply if he didn't get a bricks-and-mortar store. And thus Slough's Bike Shoppe was born.

And Shaw's is long gone, but Slough's continues. Cupertino moved again,
they were about 1/3 mile from me but were replaced by a Korean BBQ
restaurant, and moved way out on Foothill Boulevard and McClellan. But
it lost its cachet years ago.

[Sir Ridesalot]

Which is one thing that SMS spouts a lot of.

Best to just ignore him.

Cheers

[John B.]

On Mon, 23 Nov 2015 08:23:30 -0800 (PST), Sir Ridesalot
<i_am_cyc...@yahoo.ca> wrote:

>On Monday, November 23, 2015 at 6:06:35 AM UTC-5, John B. wrote:
>Snipped
>> Well, as they say, there are two methods of learning about something.
>> Read the manual, or just go ahead and have at it. The latter is
>> usually the most expensive :-)
>> --
>>
>> Cheers,
>>
>> John B.
>
>LINDBERG Plastic models used to include on the instruction sheet a cartoon of a guy tearing out his hair. Under that was the admonition, "When all else fail read the instructions".
>then again I can't understand the number of people who can't/won't follow even simple instructions.
>

Well, for God's sake! Do you think that I'm so stupid that I can't do
that? That I've got to read about it?

>I have people come to me with what should be a simple bicycle problem. I troubleshoot it and tell them what to do to correct it. Many times they ignore it and keep riding. Then tthey suffer a major failure like a collapsed wheel because they didn't get spokes replaced or tightened. One guy took apart a bunch of used cassettes to make up a custom cluster. I tod him he'd get chain skip because a lot of the cogs were badly worn as was the chain. Sure enough a few days later he's here complaining about the chain skipping when he puts pressure on the pedals but it doesn't happen i n all the gears. Duh, how do you help someone who refuses to follow simple instructions?
>
>Cheers

--

Cheers,

John B.

[jbeattie]

There is always Wheel Away! Really, though, you Google "Bicycle shops Santa Clara Valley," and you get lots of shops. I haven't done any careful research, but it doesn't look like the bicycle-shop-wasteland you describe. I know PAB and some other high-end shops are still around. BTW, Cupertino lost its cachet when Spence Wolf left, and those young guys resurrected it in the late '70s early '80s (?). I remember they had a signed jersey on the wall that belonged to Didi Thurau. I bought the first edition of the Bicycle Wheel there -- in the year it was printed, 1981? The resurrected shop was significantly more glossy than the old shop.

-- Jay Beattie.

[sms]

For "transportational" cycling there isn't much. Nothing like Clever.
The Outfitter used to have a lot but now they are part of PAB.

The population is too spread out even though it could support one such
shop if it were more concentrated. One guy did have a shop in the East
Bay decades ago but it didn't make it.

[sms]

On 11/20/2015 5:43 AM, David Scheidt wrote:
> John B. <sloc...@gmail.com> wrote:
> :On Fri, 20 Nov 2015 02:31:32 +0000, Phil W Lee <ph...@lee-family.me.uk>
> :wrote:
>
> :>Doug Landau <doug....@gmail.com> considered Wed, 18 Nov 2015
> :>14:36:45 -0800 (PST) the perfect time to write:
> :>
> :>>

> :>>> Disks are a bad idea on street bikes because they have low rolling resistance

> :>>
> :>>Disk brakes have rolling resistance?

> :>>
> :>In use, yes.
> :>It's kinda the point :)
> :>
> :>There's no reason that a properly aligned and adjusted disk caliper
> :>should drag any more than a properly aligned and adjusted rim caliper
> :>when released.
>
> :I can only comment on the one disk brake that I've actually,
> :personally, examined and it certainly "dragged", or at lest made a
> :rubbing noise when you rode the bike. The owner said that it had,
> :"always done that."
>
> It shouldn't. But there are lots of bad mechanics who can't set up a
> disk brake, same as there are mechanics who can't set up cantis.
>

> If the disk rubs, the caliper is on wrong, or the disk si bent. Som
> brakes are more difficult to get perfect than others, and crappy ones
> probably aren't wroth the trouble.

I watched a mechanic set up the disc brakes on a bicycle I bought
yesterday. There was no dragging and this was not high end.

The mechanic doing the final check was a little unhappy with the
assembler. The mechanic thought that the pads should be as close to the
rotor as possible without dragging, while the assembler wanted the brake
lever to have to be squeezed a little bit harder for the pads to engage
the rotor. I don't think either was necessarily wrong. For someone not
used to disc brakes, the amazing efficiency can be unexpected so maybe
you want them to have to squeeze the lever more than the minimum amount.

The downside of disc brakes is that there is now less incentive for a
shop to be sure that the wheel is true, and less of a clear indication
to the rider that their wheel is not true.

[Frank Krygowski]

On 11/25/2015 3:14 AM, sms wrote:
>
>
> The downside of disc brakes is that there is now less incentive for a
> shop to be sure that the wheel is true, and less of a clear indication
> to the rider that their wheel is not true.

I'm curious: Assuming a disc brake wheel is out of true only in the
lateral direction (i.e. not radial direction), what's the disadvantage
to a little imperfection?

I'm assuming it's not scraping anything else on the bike, of course.

--
- Frank Krygowski