Author Topic: Stand Reinforcement  (Read 2345 times)

Templogin

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Stand Reinforcement
« on: January 12, 2016, 08:44:12 PM »
I know that Thorn advise strongly against using stands on their bikes.  My EXP came fitted with a twin-legged Pletscher.  The previous owner had wrapped many layers of tape around the frame tubes before fitting the stand to protect the tubes.  The stand has come loose a few times so I have tightened it up, not enough to damage the tubes, but the stand has cut its way through the tape and damaged the paint.  The tubes look intact though.

I was removing the stand, planning to replace it with a Click-Stand.  It looks as though I picked the perfect moment to do this, so if you are using a stand against Thorn's advice, are you checking it regularly to make sure that all is OK?

mickeg

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Re: Stand Reinforcement
« Reply #1 on: January 12, 2016, 09:55:20 PM »
A friend of mine used the Pletscher double legged stand on his Cannondale touring bike.  The bolt locked to the stand, dissimilar metal corrosion.  He had to cut the stand off.

I do not like the double legged stands for a touring bike that uses four panniers.  That type of stand will hold the weight of two of the panniers up in the air, that puts a lot of stress on chainstays that were not designed for that kind of stress.

EDIT:  For reasons I do not understand, I can't post the first two photos that I tried to post.

I know that Thorn is opposed to stands, but if you are going to use one I think the best one to use is the Greenfield type that clamps onto the rear seat and chainstays in the back.  I do not tighten the screws too tight, and I occasionally have to re-tighten them because the screws clamp down on some plastic that is wrapped around the rear stays and the plastic deforms over time.  I use blue Locktite on kickstand screws to keep them from falling out when they get loose.  On my Nomad, the plastic piece that wraps around the seatstay did not fit well, so I instead wrapped electrical tape around it.

First photo is my Nomad kickstand.  Second photo, you can see the kickstand on my Sherpa on a rainy day.  And third photo is a beautiful dry day with my Sherpa.

Surly redesigned the LHT frame several years ago (I had the first generation LHT) before the redesign.  I used the one legged stand on my LHT that clamped on to the chainstays without any problems.  That redesign used different seat and chainstays than the first generation frames.  After that redesign, they came out with a very blunt warning that kickstands would violate the warranty, they had a lot of bike frame warranty claims where people crushed the seatstays by tightening the kickstand clamp too tight.  Fourth photo is my LHT, kickstand is up in the photo.  When there is something to lean the bike against, I usually use that instead of the kickstand.

I am not recommending that others disregard the Thorn recommendations, I am just describing what I did.
« Last Edit: January 12, 2016, 09:57:35 PM by mickeg »

mickeg

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Re: Stand Reinforcement
« Reply #2 on: January 12, 2016, 10:02:38 PM »
These are the first two photos I tried to post in my posting above.

« Last Edit: January 12, 2016, 10:08:59 PM by mickeg »

jags

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Re: Stand Reinforcement
« Reply #3 on: January 12, 2016, 10:16:04 PM »
take it off fire it over the nearest hedge  .
when you want to stop find a wall. ;)

Templogin

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Re: Stand Reinforcement
« Reply #4 on: January 12, 2016, 10:44:50 PM »
You need to ride more in northern Scotland Jags.  In a lot of places there are no walls for miles and I hate laying the bike on its panniers.

I always grease all the bolts on my bike, probably why they fall off with such monotonous regularity!  The exterior of the stand is quite corroded though.  Those stands mounted on the chainstays at the back make me even more nervous.  There isn't a lot of metalwork back there, but I see that plenty of people use them on here.

jags

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Re: Stand Reinforcement
« Reply #5 on: January 12, 2016, 11:28:38 PM »
seriously i just wouldn't trust them ,i seen a few bikes with the same stands and you could see where the ware started to set in which would lead to corrosion ,
what about the click stand they seem to be a great bit of kit.

love to tour in Scotland almost as nice as Ireland  ;D ;D but way to many tough hills for yours truly.

mickeg

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Re: Stand Reinforcement
« Reply #6 on: January 12, 2016, 11:44:34 PM »
Greasing the bolts should make them less likely to fall out.  A dry bolt if it gets loose can easily vibrate out.  But grease is a very viscous fluid, so a bolt with grease on it is less likely to fall out from vibration.

It is so convenient to dig something out of the bottom of a Backroller pannier when your bike is lying on its side ... on a rainy day.
« Last Edit: January 12, 2016, 11:47:37 PM by mickeg »

Andre Jute

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Re: Stand Reinforcement
« Reply #7 on: January 13, 2016, 12:38:15 AM »
Those stands mounted on the chainstays at the back make me even more nervous.  There isn't a lot of metalwork back there, but I see that plenty of people use them on here.

I understand where you're coming from. And I can't understand why designers don't triangulate the space immediately behind the bottom bracket and between the chainstays with a flat piece of metal, drilled and tapped for stand of either one or two legs.That's obviously the strongest point on any bike where a stand may feasibly be attached.

All the same, the rear of the non-driveside chainstay is the preferred position for attaching the kickstand of many manufacturers, including those who conduct extensive stress tests on all their frames and components and accessories. Perhaps they know something we don't.

Danneaux

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Re: Stand Reinforcement
« Reply #8 on: January 13, 2016, 01:46:50 AM »
Quote
...I can't understand why designers don't triangulate the space immediately behind the bottom bracket and between the chainstays with a flat piece of metal, drilled and tapped for stand of either one or two legs.That's obviously the strongest point on any bike where a stand may feasibly be attached.
I do understand why not, but I'm not sure I would have if I were not a hobbyist framebuilder who had mostly-successfully repaired damaged kickstand plates on several friends' bikes.

Here's why:

When a kickstand is mounted just behind the bottom bracket, the support is subject to fouling the left crankarm if it is left down and the bike is wheeled backwards. *If* the bike has also been left in a low gear, the torque exerted by the arm on the kickstand is remarkably high -- enough to break the joint that attaches the plate to the stays.

On the ones I successfully repaired, it was a clean "pop" of one side, though it was difficult to get it back in place because the plate was no longer flat. With care, I still managed some good repairs. In several other cases, the chainstay was holed when the plate tore loose -- those I could not fix, though on one I managed to braze a patch over the tear so the bike was minimally serviceable for a promised life of light use and leisure.

My first "good" bike (with a kickstand clamp and no frame mounting plate) was damaged similarly while parked in a university bike rack. Classes changed while I was inside, and a large lecture was due to start so rack space was limited. Someone managed to squeeze a bike in beside mine, but to do so, they had to pull my bike backwards a half-meter or so. I'd ridden up to campus on the hilly side, and so the bike was left in low gear with the stand down. You can imagine my dismay when I came out to find my chainstays obviously deformed by the kickstand clamp and the kickstand loose. There were no actual cracks and the bike continued for another 40,000km or so. I still have it, and still feel a little sick when I view the damage.

Also -- and I have seen this repeatedly with my own eyes at the local university! -- an astonishing number of people will actually remain seated on the bike while the kickstand is down. I'm not sure how this habit develops, but it places tremendous loads on the chainstays and can itself result in damage to the tubes. I think having the kickstand centrally mounted and easy to access while on the bike may encourage this, as I have never seen anyone balancing on a bike with a rear-mounted kickstand -- it is too hard to reach and too difficult to balance on it without falling over. Manufacturers know people can be unwise (perhaps innocent/ignorant, but still unwise) with surprising frequency, so they remove the possibility for temptation.

The reason kickstands mounted to the rear of the chainstays (near the left-rear dropout) work (better) is because the stays are rolled down as they taper and the wall thickness increases as a result (generally; there are exceptions. Road bikes sometimes use much thinner tubes throughout than mountain bikes sometimes do). It is usually harder to crush them with a clamp *and* there is no way they can be fouled by the left crankarm. The stays are further braced from bending by the rear hub, axle, and locknuts, which together form a triangulated structure laterally.

If one is going to mount a kickstand to the bike, it is less likely to cause damage near the rear hub than immediately behind the bottom bracket, no matter how it is fastened.

All of this becomes more problematic with a loaded touring bike. A low-mounted kickstand just does not have a good bracing angle against heavy loads mounted above the bike centerline. Given the already poor bracing angle, it doesn't take a lot more load from winds, slopes, or soft ground to allow gravity to have its way and the bike can fall over, causing damage from impact with the ground.

A couple (competing) manufacturers I have corresponded with feel brazing a plate to the chianstays behind the bottom bracket subjects the stays to excessive heat at their thinnest point. Others have told me they feel -- and have seen -- the weight of a heavily loaded touring bike exert enough load on the mounting plate to bend, fracture, or tear it loose. Interestingly, they noted they found the problem to be as bad with dual-leg stands as single ones. I still find this surprising, as I would expect a bike leaned to one side would develop both greater and uneven force on the stays. I'm still pondering this.

The Click-Stand and similar "tall props" work well because they brace against the top tube or where the seatstays join the seat collar and so can better prevent the bike from toppling over. The drawback is the bike can rotate around this prop, so some means must be used to clamp the brakes shut, preventing the bike from rolling using the prop as a pivot point.

So...that's likely why we don't see more dedicated kickstand mounting plates affixed to the forward end of chainstays, right behind the bottom bracket.

As a side note, many clamps do seem to dig into paint after a period of some use, leaving the metal beneath vulnerable to corrosion. I've seen various shaped rubber pads used to try and prevent this problem (Rivendell offers some for Pletscher kickstands: http://www.rivbike.com/product-p/k5.htm ), but I have seen these loosen and any grit that manages to come between does grind away on the paint.

One last observation: If you grease your mounting bolts or use a liquid threadlocker, then it is standard practice to follow (lower) wet-torque values and not (higher) dry ones. For one among many references on this, see: http://www.intermotive.net/Tech%20Tip/Tech%20Tip%20-%20Jan%2008.pdf My Glover "Pocket Ref" sees a lot of use when torquing bolts both dry and wet. Plating makes a difference also. See: http://raskcycle.com/techtip/webdoc14.html

All the best,

Dan.
« Last Edit: January 13, 2016, 02:36:41 AM by Danneaux »

Andre Jute

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Re: Stand Reinforcement
« Reply #9 on: January 13, 2016, 03:25:12 AM »
Thanks for that detailed and convincing explanation, Dan. Now I understand why people with test equipment and a history of using it braze a tab to the hub end of the non-driveside chain stay to which to attach the prop stand: it is the least bad option in the present backwards state of bicycle design.

But I'm not wearing the rest of it. While I believe every word you say, that entire story about the disasters caused by the thinned and weakened forward ends of chain stays being ripped apart by fittings for central prop stands not only leaves me cold, but enrages me by another example of the deleterious influence of roadracing on bicycle design and advancement.

In more than a century has no one had the gumption to make chainstays with long enough forward butts, or to cast or press bottom shells with long enough integrated lugs, to resist even the force of a low geared crank being wheeled backwards?

Who cares about that little weight on a touring bike if it assures its integrity?

Please note, I'm not making a case for the central stand over the hub-end stand; I'm just pointing out that refusal of those who want a central stand is not caused by some kind of an insuperable engineering problem (or even a human one, considering how impressionable people are), but by pure stodgy "traditionalism" (read "laziness") on the part of bicycle designers overinfluenced by historical road bike design, who then offer the weak excuse that they can only build with the cheap tubes available.

Personally, I like the hub-end stand attached to a tab brazed to the rear of the chain stay for the theoretical and practical advantages conferred by its greater height, wider stance, and above all because that rear three-dimensional triangle, when closed by the axle firmly bolted in, is probably the strongest structure on the bike. That seems to me the right place to attach an everyday prop stand.

But a chain stay stand that far back on the bike does need assistance when a tourer is loaded up with front panniers, and in that case, if you don't like the idea of an additional lowrider-supporting front stand, which at best is clumsy kludge and at worst worthless weight for 99% of the time, the bottom bracket stand should at least be made possible by the designer's choice of bottom bracket shell and chain stay tubes. Where he gets them is a problem designers should have solved with the tube-makers long, long ago. I ride on tubes and lugs specially made by Columbus for a single low volume handmade bike model, so I know for a fact that a key tubemaker is willing to listen to novel ideas, and I know that Poppe & Potthoff drew a few tons of specially-developed stainless steel for bike tubing a few years ago (Reynolds got the idea from P&P), with special lugs of the same material, and examples of new roadbike tubes are penny a dozen on every continent, so it isn't the tubemakers stuck in 1895, it's the bike designers.

To tell customers in 2016 to lie their bike down on the ground is unacceptable.

John Saxby

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Re: Stand Reinforcement
« Reply #10 on: January 13, 2016, 05:10:44 AM »
On my city bike, I use a simple kickstand with a twin-tube attachment bolted to the offside chain and seat stays. I use a couple of wraps of electricians' tape underneath the steel clamps to protect the paint from chafing.  This works well enough for the modest enough loads of a week's veggies & milk in 2 x 30ltr panniers.

With my Raven, I use a Click-stand, with bike-brake bands on the brake levers.  There's an argument to be made for a fixed stand on a touring bike, but I don't make it.  The Click-stand is there when I need it, as are trees, rocks, posts, fences, bridges, buildings, usw.  The click-stand has also found its most suitable hideaway in my very spiffy Revelate Tangle frame bag, and so falls readily to hand just below the top tube. You don't really need a Revelate bag to store your Click-stand, of course, any more than you really need a Raven-mit-Rohloff to go touring. Both are nice bits of kit to have, tho' :)

mickeg

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Re: Stand Reinforcement
« Reply #11 on: January 13, 2016, 05:52:43 AM »
When my bike is loaded down with camping gear, I usually lean it against something if available instead of the kickstand.  That is primarily because (1) a bike will roll if the ground is not flat, (2) the kickstand can dig into the ground, then the bike falls over, or (3) even if it appears stable on the kickstand, it still is less stable than if it was leaning against a solid wall or fence or post.  When touring, I often leave a piece of foam pipe insulation around my top tube so that if I lean the bike against a pole it is less likely to scratch the paint.

On Dan's observation of people putting down the side stand before they get off the bike, maybe they rode a motorcycle and got in the habit.  On a motorcycle I always put it on the stand before I got off the bike.  The motorcycle by itself weighed twice as much as I did, so it just made sense to do it that way.  But a bicycle, I always get off before I put down the side stand.  Sometimes on a motorcycle if I used the center stand, I first put down the side stand, got off the bike with the bike on the side stand, then I raised the side stand and lifted the bike up onto the center stand.  In this case, think of the two legged bicycle stand that is attached to the chain stays aft of the bottom bracket as being synonymous with a motorcycle center stand.

Women's hair elastic bands are not the best bicycle parking brakes, but they work reasonably well if you wrap one around the handlebar twice.  Then when you want to use it, put it over the brake levers.
https://www.dollartree.com/health-beauty/hair-care/Styling-Tools-Accessories/Basic-Solutions-Jumbo-Clasp-Free-Elastics/591c599c1200p316748/index.pro

The hill where I parked my bike in San Fransisco for the photo was rather steep, I had to use an elastic on both front and rear brake levers to keep it from rolling.

« Last Edit: January 13, 2016, 06:00:47 AM by mickeg »

Danneaux

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Re: Stand Reinforcement
« Reply #12 on: January 13, 2016, 09:49:36 AM »
Quote
Women's hair elastic bands are not the best bicycle parking brakes, but they work reasonably well if you wrap one around the handlebar twice.
I've had good long-term success using these as parking brakes: http://www.bikebrake.com/

All the best,

Dan.

Danneaux

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Re: Stand Reinforcement
« Reply #13 on: January 13, 2016, 10:37:53 PM »
Quote
To tell customers in 2016 to lie their bike down on the ground is unacceptable.
Ah, but Andre! Gravity is the most reliable of glues, and it removes one more possibility for an incautious user to file a tort claim for damages, pain and suffering, and medical bills. So much of what we see in the industry now is motivated by a great desire (if not by designers and companies, then by their insurers) to avoid lawsuits.

Also, like the old advertising maxim "Sex Sells", so does attractive design and the desire to emulate distant heroes by buying a piece of them in the form of similar equipment. And so, the vast appeal of racing-oriented design. The same is true for cars. Few people really *need* a Ferrari for their daily commute, but I (who don't own one) will readily admit the scream of a highly tuned engine is enough to raise the hairs on the back of my neck.

What most people probably *need* for errand-riding and commuting would look pretty much like the typical Dutch utility bike. what most people *want* -- it seems -- is something that looks far more flashy. Cyclists aren't the only ones to figure splashing out money on specialized equipment will equal expertise. It happens with cameras, high-end speaker systems placed in rooms with poor acoustics, hand-tooled shotguns, and the like.

And so, manufacturers go with what sells and is profitable. Adding special accommodations for kickstands adds cost and most people either do without on their bikes, clamp on a kickstand of either type and hope for the best, or go with an alternative, demountable prop-stand.

Sure, a bottom bracket shell could be cast with longer sockets to allow the thinnest of chainstays to be used. A number of MTBs now employ nontubular, machined "bridge returns" behind the BB that are uncrushable, and so on. My tandem uses arc-bent, sleeved tubes to form one-piece chain/seatstays that are incredibly robust. It is no great trick when building to use a section of ovalized tandem keel tube between an unpierced BB shell and the chainstays, then braze in a vertical tube for a kickstand to make uncrushable connection. Unfortunately, it is all work and adds expense for a benefit many consumers might see as incremental or even dubious.

Unfortunately, present designs works well enough often enough for enough people, there isn't much incentive to change. Couple that with fears of legal action and we have stasis in bicycle kickstand accommodation. Probably the most revolutionary change I've seen in kickstand accommodation is really just a small evolutionary step: Brazing a bracket to the left chainstay near the dropout or casting it as part of an extended left dropout.

I saw one of these recently -- a sort of abbreviated Click-Stand that attaches to a magnet on a tab held by the rear hub's q/r:
http://upstandingbicycle.com/ (be patient, the site takes awhile to load): http://upstandingbicycle.com/ *

Installation video here: http://upstandingbicycle.com/installation/

In its present form, it is not robust enough to support a loaded tourer. Hebie produce similar direct-axle-mounted designs with greater capability, but they are still weight-limited to 20-25kg, still insufficient to support a loaded tourer:
http://www.hebie.de/en/parking/rear-stands/ax/618/
http://www.hebie.de/en/parking/rear-stands/ax/616/

All the best,

Dan.

EDIT: *They also make a product for carrying bicycles on motorcycles: http://upstandingbicycle.com/2-x-2-cycles/ Maybe you should keep Hans the Airhead awhile longer, John....
« Last Edit: January 13, 2016, 10:45:40 PM by Danneaux »

Templogin

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Re: Stand Reinforcement
« Reply #14 on: January 13, 2016, 10:48:55 PM »
Am I alone in thinking that there used to be a stand that somehow hinged from the crossbar that had a couple of legs on it that was very robust?  Probably back in the 50s-60s though.  Or was it a figment of my imagination?