WTB Suntour CYCLONE BB Spindle

On 8/25/2019 7:10 PM, Tom Kunich wrote:
On Sunday, August 25, 2019 at 2:17:03 PM UTC-7, Chalo wrote:
Tom Kunich wrote:

Out of curiosity - why would you use an old and not very efficient
way to do things then you could buy a normal cartridge BB that will
last you the rest of your life since it is sealed to keep dirt out?

Sealed BBs don't last forever. They seem to last about as long as loose ball BBs, but with less maintenance along the way.

Square-taper sealed cartridge BBs do flex substantially more than traditional cup-and-cone BBs, because the spindle overhangs the bearings by a longer distance. The first time I saw cartridge BBs was in the new fleet of rental bikes at the shop where I worked in 1992. The first test ride I did after building one up made me think something was broken, because the pedals dove so far underneath the BB shell.

Just to get on the same page - the actual crank axle material has changed. It only requires a very small amount of chromium to greatly increase the strength of the axle. Moreover hollowing the axle out also increases the rigidity of the axle. This is what led to the octalink BB which FAR stiffer than any of the older ISO. Oh, wait, as a mechanical engineer Frank doesn't know anything about this.

OK, I let a _lot_ of Tom's nonsense go by without correction. He gets no
pass on this one.

Strength is one thing. Stiffness is another. They are not the same.

Chalo was talking about deflection of the bottom bracket and crank
assembly. Deflection for a given load is related to stiffness, and is
influenced by the shape and size of the relevant parts plus the relevant
modulus of elasticity, NOT by their strength. (In assemblies like bottom
brackets, of course any looseness in connections affects deflection, but
that's a separate matter.)

The modulus of elasticity (i.e. stiffness) is almost exactly the same
for all alloys of steel. Chromium in small amounts doesn't change it
measurably. Chromium (or other normal alloying elements) even in large
amounts barely affects it. So all steels have essentially the same
stiffness.

And - good grief! - can please we ditch the idea that a hollow tube of a
given material and outside diameter is stronger or stiffer than a solid
rod of the same diameter? It's not! How is that not obvious??

Take a hollow tube of a given material, given O.D. and given I.D. It
has a certain amount of strength and stiffness. Take a second such tube
with dimensions chosen so it just barely slides into the first. Fasten
them together appropriately. That combination has more strength and
stiffness. It _must_ because you've combined the strength and stiffness
of the two tubes!

Add another tube to the inside. Each time you do that you get more
strength and stiffness, until you've made the thing a solid bar.

Here's where a tube is better than a solid bar: If its dimensions are
appropriate, it is stronger and stiffer PER UNIT WEIGHT. That is why
bike frames and some bottom brackets are hollow. They can have more
strength and stiffness for the same weight, or less weight for the same
strength and stiffness.

(Now it's time for Tom to ask some rhetorical question that deflects or
changes the subject.)


--
- Frank Krygowski

On Sunday, August 25, 2019 at 3:14:43 PM UTC-7, Tom Kunich wrote:
On Saturday, August 24, 2019 at 11:16:11 AM UTC-7, jbeattie wrote:
On Saturday, August 24, 2019 at 10:31:32 AM UTC-7, Frank Krygowski wrote:
On 8/24/2019 12:00 PM, AMuzi wrote:
On 8/24/2019 9:27 AM, Tom Kunich wrote:
On Friday, August 23, 2019 at 10:26:14 AM UTC-7, Sir Ridesalot wrote:
Anyone here have a decent Suntour CYCLONE bottom bracket spindle
they're willing to sell? I have NOS bottom bracket cups for it.

Cheers

Out of curiosity - why would you use an old and not very efficient way
to do things then you could buy a normal cartridge BB that will last
you the rest of your life since it is sealed to keep dirt out?


I run loose-ball forged steel spindles in all my own bikes.
People weigh all sorts of factors and make reasonable choices for their
own applications as they see fit.

I've got a mix. But I've had sealed BB units fail, about as often as
loose ball units. Both have failed seldom, but in my limited experience,
it's not a night and day difference.

To me, BBs have always been a wear item. Some wear longer than others, but I've never had the same BB on a bike from the beginning of its life until the end. Some cartridge designs were horrid, like ISIS. I went through those like Kleenex. Octalink was O.K. but not great. Prior UN square drive were fairly robust. PW was robust, although I broke the center collar on one of those and had both crak arms facing forward -- which is probably a marketable invention now. I would get pitting or bad cup wear in opening bearing BBs. In the PNW, sealed bearings are nice but wiper seals are certainly not perfect. You can pull those off and find a nice, dry bearing -- hopefully not corroded.

-- Jay Beattie.

I have Record BB's here that are 35 years old. Is that what you call a wear item? And for 3 years before I had my concussion I was riding over 10,000 miles a year.

You are magical and probably ride twice a year in the rain. Try riding six months a year in the rain. But even when I lived down there in dry-ville, I pitted some NR BBs -- and broke five or six NR cranks. BBs are wear items for me. YMMV.

-- Jay Beattie.

On Sun, 25 Aug 2019 15:21:37 -0700 (PDT), Tom Kunich
wrote:

I suppose the question is - how did that water get in there to
begin with? Fording a stream deeper than the hubs?

- Partial vacuum due to temperature cycling.
- Variations in atmospheric pressure caused by changes in altitude.
- Condensation.
- High humidity.
- Washing the bicycle.
- Horizontal surfaces causing puddling.

In my past life as a marine radio designer, I had to deal with the
water incursion problem quite often. I'll spare you my list of the
common waterproofing methods that don't work. So far, the only ways
I've found that work are to either hermetically seal the package, or
to pressurize the package. Since cyclists are unlikely to do either,
the best one can do is to provide a drain path for water to leak out.
Don't worry about water getting in. Water will get in (eventually) no
matter what you do. Therefore, providing a convenient and easy to
clean exit path for the water is important. Bottom bracket drain
holes have been covered in the past:
https://www.google.com/search?q=bicycle+bottom+bracket+drain+holes
I don't have any sealed bottom bracket assemblies handy, so I can't
check if they have a drain hole. My guess(tm) is that they do not.


Jeff Lieberman etc...

On 26/8/19 7:17 am, Chalo wrote:
Tom Kunich wrote:

Out of curiosity - why would you use an old and not very efficient
way to do things then you could buy a normal cartridge BB that
will last you the rest of your life since it is sealed to keep dirt
out?

Sealed BBs don't last forever. They seem to last about as long as
loose ball BBs, but with less maintenance along the way.

Square-taper sealed cartridge BBs do flex substantially more than
traditional cup-and-cone BBs, because the spindle overhangs the
bearings by a longer distance. The first time I saw cartridge BBs
was in the new fleet of rental bikes at the shop where I worked in
1992. The first test ride I did after building one up made me think
something was broken, because the pedals dove so far underneath the
BB shell.


And then came outboard BB designs. Bigger axle diameter and bearings
closer to the crank makes for much less flex and longer lasting bearings.

--
JS

On Sunday, August 25, 2019 at 4:35:39 PM UTC-7, AMuzi wrote:
On 8/25/2019 5:21 PM, Tom Kunich wrote:
On Sunday, August 25, 2019 at 7:23:59 AM UTC-7, AMuzi wrote:
On 8/24/2019 10:33 PM, Frank Krygowski wrote:
On Saturday, August 24, 2019 at 3:49:44 PM UTC-4, Sir Ridesalot wrote:

The bike I want the Suntour Cyclone spindle is one I'm building up with the original groupset it had when new. I do NOT want a cartridge bottom bracket assembly for it.

Our 1986 Cannondale touring bikes came with SunTour Superbe sealed bottom
brackets. Mine lasted about 25 years. My wife's has less mileage, and is still
fine.

But I understand your desire to duplicate the original.

- Frank Krygowski


I'm happy that you are happy.

But everything has a measurable failure rate:
http://www.yellowjersey.org/photosfr...t/STBBRUST.JPG


I suppose he question is - how did that water get in there to begin with? Fording a stream deeper than the hubs?


Jobst repeatedly - sometimes with patience but usually not -
wrote here about the nature of wet seals. Either oil is
flowing out or everything else is flowing in. There is no magic.


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

I use Campy light grease and nothing flows either way. And I'm not in the lease particular about what I ride through on the gravel bikes.

On Sunday, August 25, 2019 at 5:00:51 PM UTC-7, jbeattie wrote:
On Sunday, August 25, 2019 at 3:14:43 PM UTC-7, Tom Kunich wrote:
On Saturday, August 24, 2019 at 11:16:11 AM UTC-7, jbeattie wrote:
On Saturday, August 24, 2019 at 10:31:32 AM UTC-7, Frank Krygowski wrote:
On 8/24/2019 12:00 PM, AMuzi wrote:
On 8/24/2019 9:27 AM, Tom Kunich wrote:
On Friday, August 23, 2019 at 10:26:14 AM UTC-7, Sir Ridesalot wrote:
Anyone here have a decent Suntour CYCLONE bottom bracket spindle
they're willing to sell? I have NOS bottom bracket cups for it.

Cheers

Out of curiosity - why would you use an old and not very efficient way
to do things then you could buy a normal cartridge BB that will last
you the rest of your life since it is sealed to keep dirt out?


I run loose-ball forged steel spindles in all my own bikes.
People weigh all sorts of factors and make reasonable choices for their
own applications as they see fit.

I've got a mix. But I've had sealed BB units fail, about as often as
loose ball units. Both have failed seldom, but in my limited experience,
it's not a night and day difference.

To me, BBs have always been a wear item. Some wear longer than others, but I've never had the same BB on a bike from the beginning of its life until the end. Some cartridge designs were horrid, like ISIS. I went through those like Kleenex. Octalink was O.K. but not great. Prior UN square drive were fairly robust. PW was robust, although I broke the center collar on one of those and had both crak arms facing forward -- which is probably a marketable invention now. I would get pitting or bad cup wear in opening bearing BBs. In the PNW, sealed bearings are nice but wiper seals are certainly not perfect. You can pull those off and find a nice, dry bearing -- hopefully not corroded.

-- Jay Beattie.

I have Record BB's here that are 35 years old. Is that what you call a wear item? And for 3 years before I had my concussion I was riding over 10,000 miles a year.

You are magical and probably ride twice a year in the rain. Try riding six months a year in the rain. But even when I lived down there in dry-ville, I pitted some NR BBs -- and broke five or six NR cranks. BBs are wear items for me. YMMV.

-- Jay Beattie.

Jay, in what world do you live where you can put in 10,000 miles per year and not ride rain or shine? Not to mention that before the 2012 water crisis you have to ride through irrigation puddles all the time. On the south end of the bay the "bay trail" was in a salt marsh and you had to ride through salt water.

Frank, stop showing your engineering inability. Did I not talk about the Octalink BB? Is that the same diameter? And since you seem to think that mild steel and Chrome Moly have the same torsional strength why do they make drive shafts on high performance cars out of chrome moly instead of mild steal since the cost difference is 200%? They do no increase the diameters.

Tom Kunich writes:

Frank, stop showing your engineering inability. Did I not talk about
the Octalink BB? Is that the same diameter? And since you seem to
think that mild steel and Chrome Moly have the same torsional strength
why do they make drive shafts on high performance cars out of chrome
moly instead of mild steal since the cost difference is 200%? They do
no increase the diameters.

It would help if you quoted the stuff you're objecting to. Frank's
point, if I understood it correctly, was that strength != stiffness.
Chalo commented on a lack of stiffness in some obsolete bottom bracket
format or another, not a lack of strength.

I believe Frank would say that CrMo and mild steel have approximately
the same stiffness, and also that he would be right.

On Mon, 26 Aug 2019 13:12:12 -0700 (PDT), Tom Kunich
wrote:

Frank, stop showing your engineering inability. Did I not talk about the Octalink BB? Is that the same diameter? And since you seem to think that mild steel and Chrome Moly have the same torsional strength why do they make drive shafts on high performance cars out of chrome moly instead of mild steal since the cost difference is 200%? They do no increase the diameters.


Hey TOM! we're taking bets on what you will change the subject to when
Frank replies to you (and shoots you down again). Care to get in on
the wager? Right now $0.10 gets you $10.00 if you guess the subject
correctly.
--

Cheers,

John B.

On Monday, 26 August 2019 18:14:12 UTC-4, John B. Slocomb wrote:
On Mon, 26 Aug 2019 13:12:12 -0700 (PDT), Tom Kunich
wrote:

Frank, stop showing your engineering inability. Did I not talk about the Octalink BB? Is that the same diameter? And since you seem to think that mild steel and Chrome Moly have the same torsional strength why do they make drive shafts on high performance cars out of chrome moly instead of mild steal since the cost difference is 200%? They do no increase the diameters.


Hey TOM! we're taking bets on what you will change the subject to when
Frank replies to you (and shoots you down again). Care to get in on
the wager? Right now $0.10 gets you $10.00 if you guess the subject
correctly.
--

Cheers,

John B.

I wish that this thread was still about someone having a Suntour Cyclone bottom bracket spindle they would be willing to part with. ;(

Sure doesn't take long here for a thread to be hijacked. That's what it is even though Frank insists it's just topic drift.

Cheers