yannisg

Recently, I was on a Brevet and I got a front wheel flat. The sealant did not seal the puncture that must had been small because I couldn't detect it. When installing the inner tube I noticed the sealant had a yellowish colour instead of white so it must have deteriorated otherwise it should have sealed the small puncture.
It was cold and dark.
When I got home and cleaned the rim I noticed that there was a corrosion hole near the valve hole. As long as the hole was small the sealant sealed it, but eventually it couldn't, and the tire went flat.


I've been using tubeless road tires since 2011 to reduce flats for the following 2 reasons.
One reason is when I race I do not have support to replace a wheel if I get a flat, and the other
on brevets so I don't have to deal with flats on a cold or rainy night.

However, I have found the following drawbacks using them.

1. The sealant leaves a "gummy" residue on the tires and rims which is difficult to remove.
2. I have had rims corrode from the sealant-alloy combination so much that had to be replaced.
3. This residue accumulates so you have to clean the tires and rims at least once a year.
4. After you clean the tires and rims they are difficult to seal again even with a compressor. So I sometimes end up replacing the tire even though it's not worn.
5. If you get a flat, and for some reason it does not seal itself, and you have to install an inner tube it's a mess.
6. When you have to install an inner tube on the road you need a small pliers to loosen the valve ring.

I would rather have a heavier puncture resistance tire than deal with above drawbacks.
Opinions pls

jadocs

What kind of sealant are you using? I'm using Orange Seal and have never seen anything like that.

yannisg

Stan's and Bontrager

jadocs

Must be some corrosive stuff to do that to an alloy rim.

yannisg

This is the 2nd rim. The 1st was a Dura Ace rim (silver Al Alloy).
It developed a corrosion crack at the valve hole, and wouldn't seal

DiabloScott

Whether or not someone finds tubeless a good option depends almost entirely on how many flats and the causes of the flats they get (or would get).

Fortunately I get only a few per year, and tubes work just fine for me, and other than maybe using lower pressures for ride quality, I have zero motivation even to consider going tubeless.

But if I had to deal with multiple flats on the same ride from little thorns and such that the GOOP works well with, I'd be looking at tubeless and accepting the mess.

jadocs

Your kidding?

Just did a cursory internet search and this appears to be a common problem with Stans due to their use of ammonia?

I would switch to Orange Seal STAT.

yannisg

IMO stan's seals holes better than CaffeLattex and Bontrager that's why I keep using it.
I have contacted Stan's about the corrosion problem, and they blame it on the alloy. Shimano blames the ammonia.

dsaul

That corrosion issue is a known problem with those Shimano tubeless rims and one layer of tubeless rim tape will prevent it. Use Orange Seal original formula and buy some large presta valve nuts. https://www.amazon.com/Vacuum-Mounta...3220096&sr=8-2

Atlas Shrugged

Much like the 7-year itch in relationships, you have a 9-year itch with tubeless and feel like it's time for a change, at least it won't cost you 1/2 of all your worth!

cxwrench

After getting onboard w/ mtb tubeless in about '07 I was ready to try it on the road a few years later...it made sense for sure. I rode it for a few years and then on my 50th b-day ride I got the cut that it wouldn't seal. At this point I had over 15 years as a pro mechanic so I was...competent. It was such a PITA fixing the cut and putting the tube in that it definitely ruined the ride. As soon as I got home I untubelessed my wheels, installed tubes and haven't ever looked back. Not enough benefits to overcome the inevitable flat/mess.

yannisg

Further to my previous posts on this topic.
I removed my rear wheel to clean the tubeless tire and rim.
I found that this rim showed sign of corrosion specially near the valve hole where a "glob" of sealant had accumulated.
It hadn't progressed so far as the front rim to become a hole, lose air and cause a flat, but eventually it would.
You can see others spots where the corrosion has started.
I sent photos of the corrosion hole on the front rim to Stan's, and there response was that the sealant is not corrosive, and its a rim problem.
When I told them that using a different sealant on Shimano rims there is no signs of corrosion I got no response from them.
When I showed the rim to the Shimano rep his response was that the sealant is corrosive.

gsa103

Stan's and Shimano rims is no-no, regardless of what Stan's says. Their response is just head in the sand BS. It's very well documented, especially for the early generation Shimano tubeless rims. You need to switch to Orange Seal. The other thing I did was wiped the inside of my rims with a thin film of Boeshield to put a protective coating on the rim.

Leisesturm

One day (like with threadless headsets) the decision will be moot. I have not so far purchased any bike with OEM tubeless tires. At least not at my <$1K price point that poverty limits me to. When or if that changes and tubeless technology matures to be as plug and play as clinchers and tubes have become. So be it. For now, "friends don't let friends go tubeless".

yannisg

The early rims were definitely more susceptible to corrosion, and Shimano prohibited the use of sealant. The next generation of rims seem to have limited corrosion. I don't think Shimano restricted the use of sealant for these rims.
I didn't pick up anywhere that Stan's and Shimano rims is a no-no. However, I did notice that when using Effetto Mariposa Caffelatex on my Shimano mtn bike rims there was no sign of corrosion.
Unfortunately, I was satisfied with Stan's sealing ability so I kept using it in my road tires.
I sent the photos to Stan's, and they replied that their sealant is non-corrosive and non-reactive, but it is wet, and that any product in your tires can cause damage to an untreated or unprotected rim surface.
I showed the rim photos to the Shimano rep who said that this is a result of a corrosive sealant.
Neither of them take any responsibility for the loss of 3 rims!

gsa103

Shimano has no reason to take responsibility, it's the result of corrosion from sealant. The rims are anodized, but there's obviously small pinholes in that allow the corrosion to start.
Stan's is clearly not going to take responsibility. You've done the experiment 3 times now, and gotten the same results. Do you believe Stan's or your experiment?

frogman

Another reason why I like clinchers...................