tubeless

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ME 109
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Re: tubeless

Post by ME 109 »

Given the option of a right angled tubeless valve, I took it.
No alteration to the rim.
No loss of air pressure over many weeks.
And......what a breeze to fit a tyre inflator on it!

I have been in the situation of riding two up, loaded for camping with a deflating tubeless rear snowflake on a twisty mountain road.
I knew the tyre was going down 'cause I could feel it.
I had the option of immediately pulling up and setting up the tent on the road as there was nowhere else, or press on the last few K's to our destination.
When we got to the destination the tyre was way flat. The tyre stayed put on the rim.
The tyre deflated because an incorrect tubeless valve had initially been fitted.
I replaced that valve with the one pictured.

A completely flat tube (blow out) will not be of any benefit in holding the tyre on the rim. imo.




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Sunbeem
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Re: tubeless

Post by Sunbeem »

Hello Twist, and thanks for bringing this up. I think I'm in a similar position to you on this matter, and have also enjoyed the thorough debate seen on these pages.

It certainly is a complex issue, and any argument which reduces it to a simple answer I automatically ignore.

My main reservation is the fairly unlikely scenario of an accident, caused by myself, or my bike, which affected someone else. (I say fairly unlikely, as it has been a rare event during the past 44 years).
Would my insurance be invalidated by some insurance assessor, because I was running tubeless, resulting in the victim being unable to claim from my insurance, and consequently suing me for having an unsafe machine ?

In practice, there are so many well-trodden ways out of an insurance contract, that the question falls into a black hole of uncertainty. And insurance doesn't stop accidents.

For that reason, the argument becomes, for me, a solely practical one, and I think the change to tubeless can be justified on grounds of safety. If my bike is therefore safer, I've taken a step towards preventing the accident, which should come as a relief to my imaginary victim.

I've not made the switch as yet, the valve detail was my final area of uncertainty. Glad you posted.

This is an area where the government, insurance companies, and BMW know we would be safer on tubeless tyres, yet regale us with threats of "tears before bedtime" should we break the ill-conceived rules they set us.

Bugger that, partial prevention is better than partial insurance.

Sunbeem.
One day more -- one day less.
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vanzen
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Re: tubeless

Post by vanzen »

wirewrkr wrote:The snowflake wheels were never designed for tubeless.
PERIOD. There's no debate about it.
True, the flake is not designed or approved for tubeless use
but functions quite well in that capacity none the less.
Three experienced benefits of the conversion:
1.) Tubeless tires can be repaired (plugged) at roadside without removing
the wheel from the MC or the tire from the wheel.
2.) Tubeless tires virtually eliminate the trauma and loss of control often associated
with the experience of a tubed-tire losing air, and
3.) The elimination of tubes reduces unsprung weight to the advantage of handling.
wirewrkr wrote:MAYBE someone has pulled it off, but it makes for a very unsafe motorcycle.
Since the mid 1970s the conversion of flakes to tubeless has been a popular owner modification –
and a popular controversy.
To say that "MAYBE someone has pulled it off"
patently ignores the valid experience of countless BMW riders and over 30 years of history.
The claim "makes a very unsafe motorcycle" is most often speculation
based upon hearsay and/or blind acceptance of the validity of legislation,
rather than the result of experience, research, or empirical study –
and patently disregards the reality of the situation.

No testing on record has ever been conducted by our legislators or BMW
to conclude that the tubeless use of flakes is unsafe.
The primary danger cited for the use of tubeless flakes echoes verbatim
the DOT reasoning to redesign MC cast wheels:
'In the event of rapid deflation, a tubeless tire on a non-approved rim may come loose from the rim.'

To which I will respond:
1.) Rapid deflation of a tubeless tire is an extremely rare occurrence.
2.) A deflated tubeless tire rarely comes off the rim, and
3.) Riding on a deflated tubeless tire is no more dangerous than riding on a deflated tube tire.
(there will be no "safety bead" to keep that tubed-thing on the rim either)
wirewrkr wrote:Even if you are silly enough to want to try it,
"Silly" ?
Why reduce your presentation to the intimidation or belittlement of those who would not agree ?
wirewrkr wrote:...you will need to have the stem hole machined to a larger size ...
Not true.
wirewrkr wrote:... and have it squared to accept the stem.
A few licks with a bastard file does it nicely.

Disclaimer:

Definite real-world road advantages exist with the use of a tubeless tire / wheel.
Those advantages can be realized using the tubeless / flake combo.
However, to do so disregards the LAW as mandated by the D.O.T. (USA)
which requires a certain profile rim (having safety beads) to be marketed for tubeless-tire operation.
and the official WORD of BMWcorp. –
which cannot recommend an activity contrary to the D.O.T. mandate
without the consequences of litigation and liability.
To do so also involves RISK on behalf of the operator should a situation
(such as sufficient impact) where the tire is forced from the rim be encountered.

My conclusion is that this potential risk is minimal
and that the every-day, every-time-you-ride advantages are worthwhile.
In consideration of my well-being, the law AND the corporate word are quite secondary
to my studied and experiential determination as to which is the safer mode.
My choice results in nearly 100,000 miles on a Type247 with tubeless flakes
without the least of detrimental consequence.

I will not presume to tell you what to think or how to proceed.
In the absence of "empirical evidence" or "definitive case study"
(no such evidence or study exists relative to the tubeless use of the BMW snowflake cast wheel),
ultimately, you "play at your own risk".

Controversy is likely to continue due to an inability to objectively quantify that "risk".
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vanzen
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Re: tubeless

Post by vanzen »

Sunbeem wrote:...My main reservation is the fairly unlikely scenario of an accident, caused by myself, or my bike, which affected someone else. (I say fairly unlikely, as it has been a rare event during the past 44 years).
Would my insurance be invalidated by some insurance assessor, because I was running tubeless, resulting in the victim being unable to claim from my insurance, and consequently suing me for having an unsafe machine ?...
I have experienced just one accident with an MC & tubeless-flakes,
but the scenario will differ in so far as the incident was not "caused by myself"
and "fault" was not attributed.
My insurance company was liable for cost of damages to myself and my MC.

Here in the states, insurance companies are not always local business concerns,
and assessors are often "generic", i.e. on-call to many insurance companies for a fee.
These assessors will simply be "doing a job", are not under pressure to "lowball' or refute a claim,
would be more comfortable assessing a contemporary automobile,
and will often know exactly SQUAT about motorcycles ...
let alone possess knowledge of the peculiar engineering and mechanical specifics
of a 30+ year old airhead.
(always be prepared to tell him/her exactly what damage has been done)

Consequently, at least in my circumstances, the event of my insurance company invalidating a claim
or a lawsuit being presented by reason of a lack of tubes in the tires will be nill ...

I do understand, however,
that modification restrictions and certification requirements for MCs
differ according to state – and are very different across the pond.
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Major Softie
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Re: tubeless

Post by Major Softie »

Perhaps, Twist, my initial reaction is now becoming clear: this is a controversy which has been argued to death - right up there with the dreaded Oil Thread. :shock:

If, I read this correctly, Vanzen has left out the primary argument against tubeless snowflakes: not the chance of unseating the bead in the event of a sudden loss of pressure (which is not any different than the chance of it happening to a tube style tire), but the sudden loss of pressure CAUSED by the unseating of the bead. The scenario in question is striking a curb or pothole and breaking the bead seal. The "safety bead" design was created primarily to prevent such an occurrence, as this is the only type of catastrophic failure that a tubeless tire could experience that the tube design is not susceptible to.

So, the argument is between the chance of such a thing happening (a complete unknown) vs. the known advantages Vanzen has listed. Many have a clear idea of how to weigh that comparison (between a completely unknown risk and known advantages). I do not. Since the actual risk is unknown, I feel more comfortable not engaging the unknown and unmeasurable risk. Many feel the same way; many feel as Vanzen does.

Good luck.
MS - out
Sunbeem
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Re: tubeless

Post by Sunbeem »

Not to disagree with anything you've said MS, but if I were to hit something hard enough to break my bead seal, I think a flat would be the very last of my problems.

Don't you ?

Sunbeem.
One day more -- one day less.
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vanzen
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Re: tubeless

Post by vanzen »

Sunbeem wrote:Not to disagree with anything you've said MS, but if I were to hit something hard enough to break my bead seal, I think a flat would be the very last of my problems.

Don't you ?

Sunbeem.
I have experienced flats with tube-tires.
Those experienceS involved an immediate lack of control on all occassions – NO FUN !
One occasion, rounding a curve at speed with a passenger,
resulted in the remnants of the tube being thrown out into the surrounding universe
and the tire being wrapped about the FD and driveshaft ...
Fortunately, the MC was brought to a halt without damage, injury, or going down.
Most fortunately on that occasion, there was no opposing traffic,
because it took both available lanes and much of the shoulders to achieve the above result.

I have experienced flats with tubeless tires –
no big deal ...
At speeds of @ 50 mph, the "squirrely" handling was an indication that something was amiss.
No trauma.
Simply pulled over when the situation allowed and dealt with it.

I have hit potholes with tubeless tires at speeds in triple digits –
Serious enough that my first thought was about bending a rim ...
(proper inflation pressures will be the best insurance to combat that)
And never did the tubeless tire break loose from the flake, NEVER ...

Just my personal experiences ...

Typically, the circumstance where a tubeless tire will leave the rim
will involve a significant lateral impact.
In which case, air or no air in the damn tire,
the essential and immediate concern will be keeping your – in the air and flying ass –
from hitting the ground without major bodily damage.

I will agree 100% with Sunbeem:
If you are riding on tubeless flakes
and whack something hard enough to take the tire off of the rim
such that the result will be rapid deflation ...
The very least of your worries will be loss of air in a tire.
Last edited by vanzen on Thu Aug 25, 2011 8:24 pm, edited 3 times in total.
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Major Softie
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Re: tubeless

Post by Major Softie »

Sunbeem wrote:Not to disagree with anything you've said MS, but if I were to hit something hard enough to break my bead seal, I think a flat would be the very last of my problems.

Don't you ?

Sunbeem.
With properly inflated tires, that's probably true, but a safety decision should never be based on things only being safe if everything is exactly the way it is supposed to be, because it never is. It would certainly seem much more likely with an under-inflated tire. It's even possible that there might be just the right angle, etc., to do it with a fully inflated tire (without your aforementioned point of that being the last of your problems). It doesn't seem likely, but no one really knows for sure.

It is not hard to imagine just the right sharp edged obstacle at just the right angle with an under-inflated tire, blah, blah, blah. As I said, the real choice is between known benefits and the completely unknown likelihood of an incident, and that leads to controversy.
MS - out
Sunbeem
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Under Pressure ...

Post by Sunbeem »

There are many reasons why we don't ride with under-inflated tyres, and I think most of us know our machines well enough to detect a soft tyre with the seat of our pants, never mind a gauge.
Or has the pre-ride tyre-check been reduced to "One, two, yep, both still there."
You raise tenacity to a new level Major.

Sunbeem.
One day more -- one day less.
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Slashsevenpig
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Re: tubeless

Post by Slashsevenpig »

wirewrkr wrote:MAYBE someone has pulled it off, but it makes for a very unsafe motorcycle.
Just keep drinkin' the koolaid ....................
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