Going Tubeless [or not] using Stans notubes.com

[Jim_Kirk]

This experiment was unsuccessful and I've abandoned the tubeless
solution. The slow loss of tire pressure is unacceptable.

I removed my Schwalbe Marathon XR from the Opti front wheel leaving
the Mavic Crosstrail Rim for this experiment.

The concept behind Stans notube system is, in theory, it will allow
you to use any rim and any tube type tire and make them tubeless.
Sounds great:
http://www.notubes.com/support_detailed.php

For the Mavic wheel you purchase this kit:
http://www.notubes.com/product_info.php/cPath/21_58/products_id/30
install the rimstrip, add the sealant and inflate by following the
directions shown above.

The Crosstrail rim is a UST [Universal System Tubeless] rim so it is
about as good as you can get for going tubeless since it is already
made to go tubeless. It should work without a rimstrip but as Stan
recommends I installed the rim strip and then followed his procedure
to the letter [and then some] to get it to stop leaking. Before
adding the sealant you inflate your tire to be sure it will hold air.
Now, you get some leakage of course [at the bead] but the sealant is
supposed to take care of that. The tire inflated so I'm thinking-
great this will work well.

Then I let the air out and removed one side of the tire, added the
sealant, reseated the tire and inflated. Again, works fine. Soap
solution [Stan's directions] shows leaks at the bead but you shake the
rim to get the sealant onto the bead and that should stop any leaks-
HAH!. Big leaks were no problem but for small leaks Stans simply
doesn't work. Here's the data after I shook the rim countless number
of times [still lost air], then I removed the air and brushed more
Stans sealant on the tire bead, inflated and shook again [still lost
air], then I called Stans and he said keep shaking so I did [still
leaked air], and then I said this is ridiculous and I collected data
on my final assembled system:

9/13/2010 40 psi
9/14/2010 38 psi
9/17/2010 33.5 psi
9/24/2010 26.5 psi

I even started all over again with a brand new Schwalbe Marathon XR
tire. Amazing, even before I added any sealant and was inflating to
test the bead seat I found air shooting out right in the center of the
tread. What is this, its a new tire? Sure enough I removed the tire,
looked at the location of the leak from inside the tire, and there was
an almost invisible imperfection right in the center of the tire. You
would never notice it with a tube but when you go tubless with a tire
that is not made as a UST you will sure notice these type of
problems. Stan's sealant would seal this leak [its a big leak] but
then I'd just be back to the slow leak problem.

While all this was data collection was happening I repeated the
procedure on my rear rim which is not UST but is a Mavic 719 disc [the
Roholoff hub is mounted to this rim]. Same problem but air loss was
worse than the UST rim. I searched on Stan's users forum for more
suggestions on how to stop the slow air leak but nothing worked. I
was so frustrated I was going to purchase a UST tires and put it on
the UST Crosstrail rim but these tires are impossible to find in
anything except full off road knobby. That is not for me.

I gave up on Stans and am now trying tire liners in each tire along
with Slime filled inner tubes. I also got a nice CO2 inflator
"mountain pipe" which I now carry:
http://www.genuineinnovations.com/bicycle/mountain/mountain-pipe.html

And, I'm back to my old procedure if the liners, slime, and CO2 don't
work. I call home for a pickup :) :)

[lowco2]

Hi Jim,
Sorry to hear you're having trouble with this. I have been using this
system for a few years and have had odd situations but overall love it
and use it with pretty much every bike I have. I even use the stuff in
my wheelbarrow wheel.
Just yesterday I was putting on a older tire on my mountain bike
(saving the mud tires for Costa Rica) and the front sealed instantly
and perfectly. The rear refused to seal, right on the rim, and even
the liquid didn't seem to be doing it. Bled out to flat overnight so I
broke the bead, cleaned it up and re-did everything. Now it's perfect,
no loss of pressure. Can't explain it, unless there was some solid
thing under the bead the first time that wouldn't let it seal.
I do a few things differently than stan does, but not radically. I
don't do the initial inflate without the sealant, just add sealant,
soap the tire and inflate up to about 40 psi with the compressor and
the internal part of the valve out. I hold it shut with my finger and
make sure the bead seated all the way around and evenly (this is an
issue sometimes). If not, deflate, break the seal, soap it again
(really a lubricant between the rim and the tire) and inflate again.
Once I'm happy with the seating of the bead (even if it's leaking) the
I reinstall the valve core and do the shake and rattle and swirl. Then
take it out for a ride. Good one to bounce the stuff around. If I
don't have time to ride it right away I know I'll have to add air
again until I can. Something about that movement really helps the
process.
Either way, sorry for your bad experience, but once you pull a nail
out of your tire and have it seal, you'll just smile and ride on...
Cheers,
--John

[Jim_Kirk]

John,
A couple of questions for you:
1. What type of rim are you using? Mavic Crosstrail? Are your rims
UST rims?
2. What brand and type of tire are you using? What is the tread
pattern, full knobby? Are these UST tires?
3. What pressure do you run at, 40 psi?
4. What is your tire pressure loss over time? 1 psi/day? 1 psi/
week?

Now I went into this experiment assuming I could get the same air loss
behavior as I had with my tube tires and I could use any tire on any
rim to achieve this. Schwalbe tires are called out on Stans web site
so, I thought, this would be easy a pie.

Stan says, in his video, that if you can inflate a tire you can seal
it, however, when I talked with Stan about my problem I was informed
some tires just don't seal [even tires of the same brand/model-some
may work some may not]. Not good since success sounds a unpredictable
to me.

The bead pattern on the Marathon XR has vertical striations [a design
feature put in by Schwalbe] to resist tire rotation under hard
braking when the tire is mounted on the rim. These striations form
little channels that make sealing the bead against small leaks almost
impossible. Now, when I say small leaks I have in mine a performance
standard of less than 1 psi pressure loss per week when starting at 40
psi. I did try riding the bike for a few miles and then I removed the
tire and did more shaking and placing the tire horizontal [per Stans
suggestion]. I shook both vertically and in small arcs like Stan
shows. No success, I just could not get my Marathon XR tires and
Mavic rims to seal small leaks.

I'd really like to see if there is a solution to this problem but I
just can't see how anyone who tries this system and is confronted with
slow pressure loss will be happy.

-Jim

[lowco2]

Hi Jim,
A few answers for you and another comment. Yesterday after making
that post, I went and filled up both the opti and my cannondale mtb
tires to exactly 30 psi on my pump just to see if there was any loss.
The mtb had fresh sealant on Sat and I can't remember when I put the
sealant in the Optibike wheels. Five wheels actually because I'm
trying different tires and discs on the mtb and have a second front
wheel for that. No loss observed overnight on any of them. I do notice
that the more I ride a bike the less loss there is, but over a few
weeks I usually have to fill up the tires. I'll keep better track. No
more than my tubed road bike, I'm pretty sure of that, but I run those
at 110 psi.

Rims: Mavic Crosstrail (UST; front on Opti); Stan's ZTR Flow (UST;
rear, Rohloff, on Opti); Shimanto XTR (UST; front on Cannondale);
Stan's ZTR Olympic (UST; rear, powertap on Cannondale). I also run
Stan's on my wife's mtb, with Mavic 117 rims (non-UST, with rimstrip)
and Mavic 517 (non-UST, with rimstrip) on my older hard-tail mtb.

Tires: Everything and anything. Recent tires include Schwable
Marathons (non-UST) on the Opti. The MTB has had Kenda Nevegals, Kenda
KOT, Kenda Small block 8, Kenda dred tread and Maxxis Crossmark (UST).
All the Kendas except a few of the Nevegals are non-UST. Also have run
Serfas (non-UST) and I'm sure a few others. The worst to get sealed
the first time were the Schwable's, but now they're great. All the mtb
tires are pretty knobby, various tread designs. The funny thing is
when I first tried the Schwables (non-UST) there were probably 3 or 4
small pin-holes in the sidewall of each. Lots of shaking to seal them,
but they did.

Pressure. Usually the Opti at 30, the mtb at 25, unless I'm on a lot
of hard-pack road, then maybe 30.

Pressure loss; stay tuned... I'll check this week.

Oh, and, I probably use more sealant than they recommend. I use 2 full
cups (the red one that comes with the sealant) per tire when setting
up new. Some tires have taken more.

Cheers,
--John

[Jim_Kirk]

John,
Interesting what you have seen with the Schwalbe tires. Amazing
that you can have such pinhole tire leaks with them but really not a
big deal with the sealant. I used 1 & 1/2 scoops of sealant and when
I disassembled the tires there was a good pool of sealant still in the
tire.
Be interested in your pressure loss numbers.
Here is a site I found before I started this experiment:
http://www.utahmountainbiking.com/goodies/go-tubeless.htm
And, this video is for John and others who ride where goat head
thorns are a problem:
http://www.youtube.com/watch?v=8E95lxyZkGw
I like the goat head dance at 3min 40sec into the video. Do
people really do this:) :)?

-Jim

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[lowco2]

Goatheads are certainly a problem around here, one of the main reasons
to run tubeless on a mtb. I have never seen that dance and, frankly,
never want to again! :-)
My bigger challenge is the junk on the roads, but event that isn't a
problem with the tubeless setup.
--J

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[Jim_Kirk]

John,
Did you get any pressure loss vs time data? Or are you still
accumulating the data?

-Jim

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[lowco2]

I did a bit, sorry should have posted some earlier...
The Optibike lost about 1-2 psi over a week. I don't have a super-
precise pressure gauge so I was relying on the on on my pump.
The mtb lost about the same, like 2 psi, but I run those lower to
begin with which might mess with it.
To me, the loss of pressure is not the issue, the ability to seal a
puncture is. Not this weekend, but the previous one I cut too close to
a rock with my rear wheel and it tore a knob on the tire enough to cut
through the sidewall. This would be fatal in a lot of cases, and I
lost a lot of pressure and had to reinflate, but made it home. That's
worth a lot.
--John

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