Tubed tyres behaving tubeless.

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SteveD
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Tubed tyres behaving tubeless.

Post by SteveD »

Over at Advrider Kai Ju wrote:
Here is a tip I've used for years on spoke/tube type wheels.
I place a couple of layers of duct tape over the rim band and follow that with a snug fitting rubber washer around the tube's valve stem. Install tube and tire and place the same kind of washer, followed with a flat steel washer, over the valve stem. Inflate as normal, tighten nut on valvestem to compress the rubber washers.
This essentially makes the tire/wheel combo act like a tubeless wheel.

Proof for me was riding home on the 405 and hitting something that actually lifted the rear wheel off the ground an inch or so. I was waiting for the tire to go flat but it didn't happen. Rode for another 15 miles, completely forgot about the incident and parked the bike in the garage.
Next morning, rolled it off the center stand and it dropped a lot farther than I expected.

What I found was a 4" long, 3/8 diameter lagbolt buried in the tire all the way to the head. Subsequent inspection showed a torn tube that should have deflated explosively, but because the air didn't leak out past the valvestem or the nipples, I was fine.
Sounds interesting. I'd be concerned with stressors around the base of the valve stem where it meets the tube proper. If the tube moved during normal operation at all I'd be concerned the valve stem might eventually split and separate. I've had that happen using the normal mounting technique.

Any opinions on the rubber washer technique?
Cheers, Steve
Victoria, S.E.Oz.


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robert
Posts: 471
Joined: Sun Jan 30, 2011 4:03 pm

Re: Tubed tyres behaving tubeless.

Post by robert »

SteveD wrote:Over at Advrider Kai Ju wrote:
Here is a tip I've used for years on spoke/tube type wheels.
I place a couple of layers of duct tape over the rim band and follow that with a snug fitting rubber washer around the tube's valve stem. Install tube and tire and place the same kind of washer, followed with a flat steel washer, over the valve stem. Inflate as normal, tighten nut on valvestem to compress the rubber washers.
This essentially makes the tire/wheel combo act like a tubeless wheel.

Proof for me was riding home on the 405 and hitting something that actually lifted the rear wheel off the ground an inch or so. I was waiting for the tire to go flat but it didn't happen. Rode for another 15 miles, completely forgot about the incident and parked the bike in the garage.
Next morning, rolled it off the center stand and it dropped a lot farther than I expected.

What I found was a 4" long, 3/8 diameter lagbolt buried in the tire all the way to the head. Subsequent inspection showed a torn tube that should have deflated explosively, but because the air didn't leak out past the valvestem or the nipples, I was fine.



Maybe seal up the spokes and run them tubeless. Why not?

Sounds interesting. I'd be concerned with stressors around the base of the valve stem where it meets the tube proper. If the tube moved during normal operation at all I'd be concerned the valve stem might eventually split and separate. I've had that happen using the normal mounting technique.

Any opinions on the rubber washer technique?
Duane Ausherman
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Re: Tubed tyres behaving tubeless.

Post by Duane Ausherman »

It used to be that a tire would move on the rim and drag the tube along with it. That would rip out the tube stem and go flat very quickly. That is the reason for not running the two nuts down to the rim, but to jam them together about 1/2 way up the stem. This allows one to see the stem start to tilt over and one knows that it is about to rip out.

I thought that I had this spelled out on my website, but I can't find it now.

Never put the nut on the inside.
Ask the Indians what happens when you don't control immigration.
ME 109
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Re: Tubed tyres behaving tubeless.

Post by ME 109 »

Duane Ausherman wrote:
I thought that I had this spelled out on my website, but I can't find it now.
It's here... http://w6rec.com/

I found it on google under 'Duane Ausherman'
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Kurt in S.A.
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Joined: Tue Aug 03, 2010 12:08 pm

Re: Tubed tyres behaving tubeless.

Post by Kurt in S.A. »

See "More tire mounting errors" at the bottom:

http://www.w6rec.com/duane/bmw/tire/

Kurt in S.A.
PAS
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Re: Tubed tyres behaving tubeless.

Post by PAS »

A service bulletin from January 1982
36 017 83 (2066) states" For riders safety,the valve stem nut must absolutely be screwed up against the cap and not touch the rim."
Duane Ausherman
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Re: Tubed tyres behaving tubeless.

Post by Duane Ausherman »

Kurt in S.A. wrote:See "More tire mounting errors" at the bottom:

http://www.w6rec.com/duane/bmw/tire/

Kurt in S.A.
Thanks Kurt, I tried Google and failed, but I gave up quickly because I was busy with something else. Sometimes I use the Google search feature on my site, but faster is to just put "w6rec tire mounting" into Google. This time it worked.

Has anybody used this page? Was it useful in any way? Correct tire and tube mounting and balancing are very important for safe riding and reliability.

I really am keeping questions saved up to use when I get back to working on my website again.
Ask the Indians what happens when you don't control immigration.
barryh
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Re: Tubed tyres behaving tubeless.

Post by barryh »

SteveD wrote:Any opinions on the rubber washer technique?
I've done something similar for years on snowflakes. The valves stem hole is a larger diameter than the valve stem. Just big enough to slide one or two small O ring into the gap and for the stem nut to be loosely tightened down onto that. I don't pretend it's air tight but It should slow down any leak. I'm aware of the possibility of the tube rotating but it's never happened and there is a little give in the O rings. I wonder if tube rotation is still such a problem with the higher tire pressures used on modern tires. You could use rim clamps. I remember my T140V having rim clamps but they were an additional pain when it came to tire changing. I remember a Trials bike having them and for that application they were really needed with the very low pressures used.
barry
Cheshire
England
daz
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Joined: Wed Aug 04, 2010 4:07 pm
Location: Ohio

Re: Tubed tyres behaving tubeless.

Post by daz »

Silicon James
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Major Softie
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Re: Tubed tyres behaving tubeless.

Post by Major Softie »

daz wrote:Silicon James
AAAAAAUUUUUUUUUUUUGGGGGGGGGHHHHHHHHHHHH!
MS - out
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