GhostRider62

I put a set of Continental GP5000S tubeless on last Thursday and did a short ride Friday. They held air overnight and then I did a 125 mile ride Saturday starting at 85 psi and finishing at 63 psi or a couple hours later measured at home. I could feel it when climbing out of the saddle, the tires felt wiggly.

Any insight? Where did the air go?

Park video at 5:20 says it can take days to seal. I bought a different sealant formulation and will try that.

Iride01 

Scotty beamed some out!

Or perhaps you got a puncture that didn't seal immediately. Or like the video and you said, it can take awhile for things to seal up.

alcjphil

Did you check the tire pressure just before your 125 mile ride, or was that the pressure you had in the tires before your first ride the day before? What sort of pressure gauge did you use? What size are the tires? The narrower they are, the faster they will lose pressure. Some tubeless tires lose more pressure than others. I haven't checked the pressure of the tires on my gravel bike for almost a week and they don't seem to be losing much as per a squeeze check, but they are higher volume and much lower pressure tires.

Barry2 

I never had a sealing issue with 5000 TL
My new as of yesterday 5000 S TR seem to be having some leakage.
I did find a youtube that claims S TR leak through the sidewall.

I'll give em a couple of days and see.

Barry

I found the Video.

GhostRider62

Pressure checked at 4 am on Saturday. Topped off with EVT and compressor, double checked with a digital gage. 85 psi, for sure. Triple checked with thumb. 700 x 25 mm tires. Got home that evening and they were both around 63 psi although I recall one being 65 psi. As indicated, I could feel them being squishy deeper into the ride when getting out of the saddle on short hills. They lost a couple two or three PSI per day over the next two days. Neither tread has any indication of a puncture or glass. They look new.

The only thing I can think of is to beef up the sealant from Endurance to Orange Regular. 20 psi loss on a ride is no good. I never lost more than 10 psi per 24 hours on latex tubes. I started and finished PBP with latex tubes and never even topped them up during the ride. I used Tesa Polypropylene tape with two wraps.

Any tests that I can conduct to find the problem? Or just be patient, it will resolve in time?

cxwrench

How can you expect anyone here to be able to give you an answer? It could be a problem with the rim tape, the valve, the valve core...who knows? Impossible to say w/o seeing it.

GhostRider62

There are a lot of smart asses here, I figured someone had had such a problem.

I replaced the valves. I also replaced the stems with a different make.

If the tire does not leak overnight, how the hell can it be the tape? You think seeing it would help?

I did notice after todays 2 hour ride that one tire was down 7 psi. There was a small trace sealant on the rim from the bead like a fart or something. Weird.

I'll post the solution when I figure it out.

cxwrench

What kind of time, what kind of tape? Where is the overlap of the tape? What kind of valves? You sure they're tight enough? Valve cores are tight? Any dents in the rim? I have to fix TL stuff all the time, we always get it figured out. We just had a really stupid one w/ some WTB rims (which I cannot stand) that didn't come w/ all of the parts to make it work correctly.

GhostRider62

I do not know what you mean about what kind of time? I lost 20 psi in under 24 hours. The loss is when riding. Not when the sitting in the garage. I lost 7 psi on a short 2 hour ride today on crappy roads.

I already said the tape. I pulled as hard as this 230 pounder can pull. The overlap of two full layers is at the valve hole. I actually tried three different stems. I used two different valves. Yes, they are tight. I have been riding for almost 50 years and more miles than you could accept.

I am pretty sure the air is being lost thru the sidewalls but only when I hit bumps. I had a similar problem during the Transam bike race, losing air in under two hours and having to fill the tubed clinchers. It drove me crazy. It turned out to be defective seams on the Schwalbe tubes that only manifested under load. Eventually, I could duplicate in the bathtube under pressure. WRT to these tubeless tires, they might need a higher viscosity sealant, which is why I have put Orange Regular in to replace the Endurance.

There is a youtube out there showing the sidewall leaks as another poster mentioned. This would explain the sealant pissed on my rim after today's ride. The bead seal appears good on both, so, I doubt the leak is there and if it were, I would expect much more than the current air loss.

This reminds me to a lesser extent of my tubeless experience with Compass tires but to a lessor extent for sure. I could see the leaks on the Compass sidewalls, but I cannot see them on these tires. The "holes" in the sidewall are small and under static conditions, there is not much leakage. But under dynamic riding conditions, there is more pressure variation and that is when the leakage occurred with the Compass tires and potentially, this is the issue with these GP5000S tubeless tires.

tFUnK

I suspect a seating issue. You might try to install tubes, pump up to 100 psi, and let it sit like that for a day or two. Then remove the tube and add sealant and check for leakage. This way you can at least ensure that the bead is properly seated and whether the air leak only happens out in the road or if it also happens while stationary. If air leaks only occur during riding, it could be burping or losing air/sealant on small micro punctures.

GhostRider62

Thanks, I'll follow-up with the solution. They are seated properly.

I suspect the sidewalls need the help of thicker sealant, which is why I changed from Orange Endurance to Regular. I found this video about GP5000S sidewalls. I am not keen on dunking my rims into a water bath. I had this problem with my initial foray into tubeless when mounting Compass aka Herse extralight tires, but they were so porous that the sealant would ooze out, I am not having that level of leak. It will take me several days to sort it out. This is already day 6 and I have mounted and remounted several times. They pop right into place using my compressor with the bead evenly around the rim with perfect lateral and radial runout. When I have had a seating problem in the past, I could see it in the lack of perfect true.

tFUnK

Since they seat readily, it may be worthwhile to pump them to a higher pressure and let it sit like that to ensure they stretch/settle properly. May not help but can't hurt (don't exceed the max pressure rating for the tire or rim).

tankist

After putting in sealant did you rotate the wheel in all directions and let it lie on the side and then the other side for a while? This way sealant will be able to seal potential leaks between rim and tire.

GhostRider62

Yes. Innumerable rotations with oscillatory motion to ensure sealant goes all over the place. Side to side.

I only lose a couple pounds per day on both tires if the wheels are not used. The issue is when riding, it is something like 2 psi per hour lost. I have not ridden them since changing to a different sealant and am hoping this will bring the lose down. If not, I'll mount a different set of tires to verify the leak is the tires.

vespasianus

You need to find out where the air is coming from. Pump it to high pressure and spray it with soapy water. You will see bubbles from even the smallest leak of air. If the sidewalls, use more sealant. Sometimes the first installation of a tubeless tire needs more sealant. If the bubbles forms around the spokes, it is the tape. If it is valve stem, it is either the valve stem or the tape. When I install the valve stem, I always add some grease to the rubble part of the valve to help create a good seal.

Also, if it is getting worse over time, it is the tape. If it is only loosing air when weight is put on it, it is not seated properly.

GhostRider62

The problem is porous sidewalls just like the video that I linked. No leakage with soapy water on the stem, bead or spoke holes.

I submerged the wheel into the bath tub and little bubbles appear all over the sidewall. If I load the tire with my weight, more bubbles appear and they come out quicker. The sidewalls leak, pure and simple. Investigation closed on my side. GL to all.

Like I indicated in an earlier post, these are not as leaky as some old Compass extralegere tires but they lose about 2-4x the amount as latex tubed clinchers and unless they improve, they are not acceptable for my application on long rides. Again, they do not lose much air just sitting around. They lose a lot of air on a 10-11 hour ride, approx. 20 psi

masi61

I’m going to venture a guess that it is the tape but it might help to know the brand of rims and the brand of valves. To me it seems there are many ways that cone shaped universal tubeless valves leak on a road tubeless rim. To me the rectangular type seal better. When it is the correct valve you can do finger tight on the nut.

Also, about the TESA tape. You said you pulled it tight, but I guess my question is “did you smooth it down to remove any air bubbles and verify that it runs up to the bead shelf with dipping and getting anywhere near spoke holes?” I had the same experience as you on my DT Swiss and rim tape. Honestly, I’m thinking of using a heat gun next time I do a tape job then using a plastic tire lever to make absolutely certain layer one is completely flat before applying layer 2.

Curious to know what your definitive diagnosis is. You will figure it out eventually.

GhostRider62

It is the sidewalls, see my previous post. For a visual, look at the youtube video that I posted earlier.

After a week and 200 miles, I am not hopeful that my last action of changing from Orange Endurance to Regular is going to help but it might. If I can cut the pressure loss while riding in half, it would be ok. I would just air up every day and if doing a long brevet, I'd add air during the event halfway but the current loss during a long ride is too high. Who cares about 4 psi on a 2-3 hour ride but 20-25 psi on say 300Km presents different issues that I cannot accept. I have some Vittoria Speeds that I will mount but not anytime soon. Part of this is my bumpy roads and 230 pound total bike/rider weight and preference for 85-90 psi on 25mm tires. Put a lighter rider with lower pressure and better roads and the sidewall leakage rate would be different. They are very comfortable tires with good grip, so, no complains there.

GhostRider62

With Orange Regular sealant, mine do not leak as bad as this video but the little bubbles look similar. If I oscillate my weight up and down on the rim, more bubbles appear and there is more rapid loss at existing ones. I could accept a 10 psi loss on a long ride but not 20. I am only losing 2 psi over 12-20 hours of the bike just sitting in the garage, so, that is very trivial. I'm doing a longish ride today and will be curious to see the leakage loss because this would be my first good ride since purging the Orange Endurance and putting brand new Orange Regular it, which clearly is more viscous.

vespasianus

Clearly, you just have a more porous tire. You need more sealant. Oh, also, I have never ever use sealant without glitter. Something from the early days of MTB tubeless learning 15 years ago. I would just open that up, add about 40ml of sealant and a large tablespoon of very small glitter.

GhostRider62

Not just one tire, it is both front and rear. I have two more GP5000S spare, I could mount them and test.

Could you explain why I need more sealant? I syringed a bit towards the high side of recommended amount. How much would be enough?? It is a 25 mm tire. If I was talking about a puncture flat that did not seal and if I ran out of sealant, your comment might make sense to me.

I used to use glitter instead of foil, the Hanson brothers had it all wrong.

trailangel

Yes.. it is the sidewalls. Contis are known to do this. I don't ride tubeless on road tires but I do on MTB tires. And will not purchase Contis with the light colored sidewalls because they weep and leak. I choose a tire that will hold air without sealant.... then remove the valve core and add the sealant after I know there are no leaks.

vespasianus

Put enough in so that it seals. You should not have air seepage if the sealant is doing it job.

GhostRider62

More sealant will not help. At 6 o'clock, the sealant covers the entire inner sidewall and therefore, the entire casing is bathed while rotating. I have around 50-55 ml inside a 25 mm tire. I have not needed that much in the past.

What I am going to try is lowering the pressure and rotating to bath the inner sidewall. Then apply heat with hair dryer or heat gun on low. Flip and repeat on the other side. This process might build up a sufficient layer of latex to prevent air bubbles from escaping. I am not giving up yet. A week and $500 of junk so far, hope to make these puppies work. I'll give it a couple months or until these two tires are worn out. If not, I am going back to clinchers and latex tubes.

scottfsmith

I have had this same weeping sidewall issue on two different brands not Conti. With Vittoria Terreno Dry one was so bad I returned it. My current Specialized S-Works Rapidair Turbo's have one tire with a slow leak on the sidewall. I did get it better by keeping it on its side for a long time.

I have some of the GP5000 S TR but have not mounted them yet as my Rapidairs I got working well enough.

What I would recommend is to take both tires off, pump up to the max, and put them on their sides on the ground. Every couple hours rotate 45 degrees or so the lowest point on the tire (the point touching the ground). Get all the way around, then flip and repeat on the other side. I did something like this on my Rapidairs and the bad one is now doing the same as the good one in terms of losing air.. 3psi per day or so. I use the Panaracer sealant for what its worth.

Curious if you have the tan sidewalls or not as per above comment about those being worse.