[ToffieBoi]

Hello everyone.
I have a question with tubeless tires. They are my first tubeless set so I don't have enough experience, if it is normal or not.

Information about me;
I am riding on a Tarmac with Ultegra set. Ultegra 6700 wheels and Hutchinson Fusion 2 tires. I weight around 65kg and bike is around 9 with water and everything.
I am riding on 80PSI in the front and 90 on the rear. I don't have sealant on the front tire (but I had the same problem while I had)

My problem is;
While I am passing some bumps and holes on the tarmac, usually with a sharp edge, I am hearing the air is leaking from the tire, like "psssss" sound. Also it happened on the cobbles several times too.

I believe that the bead is releasing for a second from the rim, and there is a little air leak, and they hold again. Or it is just the air sound when they have hit from outside.

The question is;
Is that sound normal with tubeless tires? Should I be worried about sharp cornering or anything else?

 

[Dersnap]

For sealant to work usually it needs to be worked around a bit. It is possible you are burping air. What worries me is that this could also happen if the carbon belt has broken. I would double check this to be sure ad I had one blow out on me. Lucky for me I was just sitting as going fast would be serious accident.

I can't understand why not running sealant ?

 

[ToffieBoi]

For sealant to work usually it needs to be worked around a bit. It is possible you are burping air. What worries me is that this could also happen if the carbon belt has broken. I would double check this to be sure ad I had one blow out on me. Lucky for me I was just sitting as going fast would be serious accident.

I can't understand why not running sealant ?

Thanks for answer. Why I don't ride on sealant;

I am riding on Fusion 2's now. I had a small cut on my front tyre, which is like less than 1mm inside the tyre.
First, my Joe's Road Bike Sealant fixed it and it was good for one month. One month without riding because I moved to Krakow / Poland from Istanbul / Turkey.
And then on my first ride here, everything was cool. But I was riding on lower pressure.

On my second ride, I pumped up my tires up to 90PSI and after a bump it started to leak from the old puncture. After 10 minutes of slow ride and getting covered with latex everywhere on my bike and face (it was fixing and in 10 seconds leaking again), I decided to stop and put an inner tube. And trust me, it is not funny to clean all that latex from the bike and glasses.

After I came home I fixed the puncture with a tubeless patch and now tyre is standing without any sealant in it, for more than a week and I even didn't lose 5PSI

Long story short, I don't trust sealants anymore. Maybe Joe's is not a good brand or something but still...
Now, I have some more in my rear tyre but I will just get rid of this and I will run without sealants. I think high pressure in road bike is too much for sealant, I don't know.
And in case of puncture, I will just carry a spare tube, like we always do with regular clinchers.

 

[cxwrench]

Thanks for answer. Why I don't ride on sealant;

i have used Stans for years. i'm sure i've punctured in that time, but it's never caused me to stop. Joe's? never heard of it.

 

[mikerp]

Sounds as if you are loosing air when you cross edges, similar to when you would be getting a pinch flat at too low of a pressure with a tube. The obvious answer would be add pressure, even though you are running tubeless wheels and tubeless tires. Supposedly Shimano recommends not using sealant with their wheels (corrosion issues). Sealant is an extra layer of protection, not reqd in this case. Are you leaking on both wheels or just one? If just one, you may have some damage.

 

[ToffieBoi]

i have used Stans for years. i'm sure i've punctured in that time, but it's never caused me to stop. Joe's? never heard of it.

I read that cuts are a bit different than punctures because they flex and make sealant fix impossible. It can be true...
Joe's No-Flats

Thats what my Specialized dealer was selling. We don't have Stan's in Turkey.

Sounds as if you are loosing air when you cross edges, similar to when you would be getting a pinch flat at too low of a pressure with a tube. The obvious answer would be add pressure, even though you are running tubeless wheels and tubeless tires. Supposedly Shimano recommends not using sealant with their wheels (corrosion issues). Sealant is an extra layer of protection, not reqd in this case. Are you leaking on both wheels or just one? If just one, you may have some damage.

I am able to hear front tire more because when I hit the same bump with rear, I am also hearing the chain and others. So it is not really easy to differentiate (I don't know if there is a word like that, sorry) the sounds coming in one time.
But I will change my front and rear tyre after my first ride and try them.

 

[Jay Strongbow]

I am able to hear front tire more because when I hit the same bump with rear, I am also hearing the chain and others. So it is not really easy to differentiate (I don't know if there is a word like that, sorry) the sounds coming in one time.
But I will change my front and rear tyre after my first ride and try them.

I'm guessing this has nothing to do with your tires. If you were losing air every time you hit a bump to the point you could hear it over the wind in your ears your tire would be flat, or close to it, pretty quick. Or did that happen?

 

[ToffieBoi]

I'm guessing this has nothing to do with your tires. If you were losing air every time you hit a bump to the point you could hear it over the wind in your ears your tire would be flat, or close to it, pretty quick. Or did that happen?

It happens once or twice per ride. Because I don't have many rough roads here and usually I am able to not hit the bump. But sometimes I can't and I am hearing that noise.
I didn't check the pressure after my rides so I don't know if I lose so much or just 1 or 2 PSI...