Carbon wheels delaminating?

graememacd

I recently bought some carbon clinchers from a reputable wheel builder (not one that frequents these forums). I set them up as tubeless but the rear would lose pressure sometimes over a day other times over several days. I tried re taping the rims to rule that out but it kept happening. After one ride I noticed Tyre sealant on the brake track but didn't think anything of it. After my last ride I checked the wheels the next day and found the sealant residue shown in the picture. Is that the brake track delaminating?
They have only done 250 miles and the wheel builder has had them back and told me they're fine while ignoring the photos I've sent. They also said they will only refund 60% of the value.

trailflow

Never seen that before. Is the sealant leaking out from the bottom of the brake track ? If you squeeze the rim does the gap open up and leak more ?

That doesn't look fine. How can it be normal ? Looks like a manufacturing fault.

I think they should replace the rim or wheel or refund.

60% refund is also not on. You could name and shame.

graememacd

trailflow wrote:

Never seen that before. Is the sealant leaking out from the bottom of the brake track ? If you squeeze the rim does the gap open up and leak more ?

That doesn't look fine. How can it be normal ? Looks like a manufacturing fault.

I think they should replace the rim or wheel or refund.

60% refund is also not on. You could name and shame.

The rim doesn't open up if you squeeze the brakes but it's quite clear that it's leaking. There was another section of the rim where it was the same. They did offer to replace the rim initially before they had them back but said it would be 3-4 weeks before they would have any more in stock. Since they've had them back they have blamed the stans tape I used saying it was to loose. I taped it twice to make sure after it lost pressure, plus that wouldn't make any difference.
I won't name and shame (yet) as the build quality was good but if they stick to their story I will contact trading standards

Lookyhere

graememacd wrote:

I recently bought some carbon clinchers from a reputable wheel builder (not one that frequents these forums). I set them up as tubeless but the rear would lose pressure sometimes over a day other times over several days. I tried re taping the rims to rule that out but it kept happening. After one ride I noticed Tyre sealant on the brake track but didn't think anything of it. After my last ride I checked the wheels the next day and found the sealant residue shown in the picture. Is that the brake track delaminating?
They have only done 250 miles and the wheel builder has had them back and told me they're fine while ignoring the photos I've sent. They also said they will only refund 60% of the value.

Obviously faulty and equally obviously not very reputable at all....name so we can all avoid.

If you paid by CC you can make a claim against the CC provider ie Halifax, lloyds etc etc

You ll get no-where with trading standards.

graememacd

Unfortunately I paid via bank transfer so no come back. I wish I'd paid through their ebay shop now. I have threatened them with trading standards so will see what their response is before naming them

trailflow

Any reason why you don't want to wait 3-4 weeks for a replacement? or do you want a full refund ? or have they backed out of the deal ?

graememacd

Because I have my best bike sitting there with no wheels on it. Plus I'm not sure I trust the rims. Anyway they seem to think that the rim is fine even with the evidence so not sure the offer is still on the table. They have offered to send them back but I have to pay for their rim tape which they've added

cycleclinic

sealant leakage can happen if the tape does not seal the rim that for the tyre is not sealaing against the rim properly. Witht he tyre deflated does the tyre fall away from the rim.
there is some wet marks just above the brake track and just below the tyre. could the leak be from the tyre rim interface.

Delamanination is not what I am seeing there would be a crack or something obviously wrong with the carbon.

I suspect this a tyre rim problem not a delamination problem. If the wheel is true and round there nowt wrong with the rim.

you can trust the rims though. Is this a tubeless compatible rim we dont even know that.

graememacd

The Tyre does not fall away from the rim when deflated and yes they are tubeless rims

cycleclinic

well even so it still might be a tyre/rim interface problem given the sealant just below the tyre. the brake pads remove the sealant from the brake track.

I still cant see any evidence of delammination. not all rims are tubeless compatible as they should be and sometimes it is the tyre.

The wheel builder maybe right by not offering a full refund there maybe nothing wrong with the rim. have you tried another tubeless tyre for example.

Letting the retailer sort the problem is not a bad option I would let them. maybe they can set it up for you so it holds air and does not leak.

Also no offence here but I get number of wheel issues which turn out not to be the wheel but something over looked y the customer like Q/R used e.t.c. So dont rule out the taping. just because you have done it twice does not mean that it done right. It may not be the tape also but dont rule it out either.

I also would not name and shame it would not be fair as the cause of the problem from these pics is highly uncertain.

If your really worried sent it me. I will have a go a taping it and sealing the tyre. I will even ride the thing and if I never get back to you its because the rim killed me. otherwise I will send it back. you will know then if it is the rim or something you have over looked.

In short be less worried about the rim, carbon does not just crumble into dust. look for the simple cause rather than assuming it is the wheel which in my experience is the default cause identifed by customers even though the fault maybe something else.

graememacd

There was no evidence of the Tyre leaking at the rim and this happened after the ride with the bike stationary

cycleclinic

so whats that in the photos below the tyre then? looks like sealant marks to me.

I can see the problem. Look very closely the tyre is not seated properly it looks taller to the right of the photo than on the left. If I am right in this (I may not be) over inflating will allow the tyre to pop into place and seal properly.

Some soapy water when installing the tyre will help avoid this in future if this is the cause.

graememacd

It looks like one sealant mark but doesn't explain the rest of them. Think I'll stick to handbuilts in future....

cycleclinic

what about the way the tyre is sitting is still looks like it is sitting low. If that is right then the rim is not at fault.

you are looking for problems what may have very simple causes. there is no evidence of rim delamination so rule that out until there is.

trailflow

I agree the tyre looks to be not seated properly. I'm leaning towards the pads wiping away the sealant which leaked out of the tyre. That's why there is big spot where the tyre is at it's loosest and a couple of small wet spot at the top of the brake track directly inline with the rest underneath. And most of it seaped to the bottom of the brake track. Then the wind smudged it across the rim.

If there is a hole at the bottom of the brake track, then surely there is another hole somewhere inside the rim bed you could check. Try shining a torch in the rim bed, in theory the light should shine through and come out of the hole if there is one at the bottom of the brake track.

Delamination is where the bead hooks/brake track overheat,melt,weaken,warp, causing it to widen. And usually happens at the top of the brake track. To check, measure how wide the rim beads are at various point along the rim. Both inside and out. You might want to take the tyre of to do it properly. Alternatively you could spin the wheel and look next to the brake pads (adjust them closer) and eye ball it for any bulging. Similar to checking how true a wheel is.

graememacd

Looks like that might be the case, I'm having the wheels back anyway. Thanks all for the input

cougie

Yeah I'm going with the tyre rim interface. It's the most obvious explanation.

ugo.santalucia

I am thinking why I have never sen carbon wheels used in Formula 1 or similar... I remain to be convinced that carbon fibre is a suitable material for tubeless

graememacd

ugo.santalucia wrote:

I am thinking why I have never sen carbon wheels used in Formula 1 or similar... I remain to be convinced that carbon fibre is a suitable material for tubeless

F1 wheels are magnesium as carbon fibre is banned in the regs. Not sure if it's a safety thing or for cost though

ugo.santalucia

graememacd wrote:

ugo.santalucia wrote:

I am thinking why I have never sen carbon wheels used in Formula 1 or similar... I remain to be convinced that carbon fibre is a suitable material for tubeless

F1 wheels are magnesium as carbon fibre is banned in the regs. Not sure if it's a safety thing or for cost though

Probably they don't like the way it shatters, but a lot of the rest of the car is made out of it, so hard to say. Or maybe they are not considered safe for tubeless.

Did you know lorry tyres go up to 120 PSI? :shock:

davetex

Superbikes use carbon I think, so I guess F1 could if they wanted

cycleclinic

ugo I run tubeless tyres on my carbon rims no issues. no issue with the team wheels either or other customers. tubeless works on carbon rims. the installer though needs to enure the tyre is seated right. For me they have always popped into place by 110 psi then I can let some air out once the tyre is seated right. As I have said some lubricant on the bead helps a lot.

What does having the wheels back mean. is the OP keeping them or sending them back.

graememacd

I had sent them back but they're now coming back to me. I'm happy after looking again that it's not the brake track and reassurance from the wheel builder. Just need to find some dry days to ride them now...

cycleclinic

I think F1 cars do not use CF wheels because the spin at very high speeds putting the wheel under constant stress from the centripetal force add to that the constant impact from hitting curbs at 200 mph it is probably an accident waiting to happen.

To give an example of how tough CF is and well tubeless tyres work with them one team rider has nasty crash this year. straight into a metal barrier at speed. The wheel suffered (rider dazed but O.K) and the CF fractured. The tubeless tyre did not deflate though as the rim bed with the tape remained air tight. No part of the wheel detacthed either. All spokes remained in the spoke nipple bed. It was still wheel shaped and the tyre was removed and refitted. Tubeless and CF works. CF can fail but is a compostite it wont crumble into dust.

the reason why I have given a team some wheels is to see what happen when crashes happen. On came back after a crash and a pedal had gone through the rim. It was still straight, tyre inflated and quite rideable. try that with an alloy rim.

JoostG

I can only advise you to be really careful with your wheel issue. Last holiday I had a same issue with a tubeless carbon rim: it was more or less "sweating" latex stationary. I checked it over and over but couldn't find an answer. But it didn't seem to offer any issues. After a beautiful climb to the top of the Col de Tentes, I went down. After a few hairpins and just a couple of times braking, I heard a loud crack whilst coming out of an hairpin. Within a second I was on the ground: the upper part of the breaking area had cracked open over 20cm. I don't know what happened, but after reading this topic I start thinking that their could be relation between the "sweating of latex" and the crash.

trivial_poursuivant

How old are the wheels? You could threaten the shop with legal action if you can prove the wheels are not fit for purpose and the defect prevents use. Only thing that may stop this is if you can still use them as standard clinchers since they could argue that's how they were meant to be used. If they were sold as tubeless ready you may have a case.

JoostG

Trivial poursuivant wrote:

How old are the wheels? You could threaten the shop with legal action if you can prove the wheels are not fit for purpose and the defect prevents use. Only thing that may stop this is if you can still use them as standard clinchers since they could argue that's how they were meant to be used. If they were sold as tubeless ready you may have a case.

The wheels are approx 2.5 years old and did between 5.000 - 7.500km (mostly in dry and flat conditions). I send pictures to the manufacturer and now I have to wait for a reaction. They were sold as tubeless ready. The hardest thing will be to determine what caused the crack. We'll see...
Next mountain adventure will be with my disc brake bike with alloy rims.

trivial_poursuivant

JoostG wrote:

Trivial poursuivant wrote:

How old are the wheels? You could threaten the shop with legal action if you can prove the wheels are not fit for purpose and the defect prevents use. Only thing that may stop this is if you can still use them as standard clinchers since they could argue that's how they were meant to be used. If they were sold as tubeless ready you may have a case.

The wheels are approx 2.5 years old and did between 5.000 - 7.500km (mostly in dry and flat conditions). I send pictures to the manufacturer and now I have to wait for a reaction. They were sold as tubeless ready. The hardest thing will be to determine what caused the crack. We'll see...
Next mountain adventure will be with my disc brake bike with alloy rims.

Over 2 years is a long time (you said recently) and I'll be surprised if you get anywhere. I was thinking they were a few weeks or months old. Hope you get something, I would think the 60% offer if you get it quite reasonable after the length of time you mention. They have only your word as to how well you look after them or the level of use.

veronese68

Trivial poursuivant wrote:

JoostG wrote:

Trivial poursuivant wrote:

How old are the wheels? You could threaten the shop with legal action if you can prove the wheels are not fit for purpose and the defect prevents use. Only thing that may stop this is if you can still use them as standard clinchers since they could argue that's how they were meant to be used. If they were sold as tubeless ready you may have a case.

The wheels are approx 2.5 years old and did between 5.000 - 7.500km (mostly in dry and flat conditions). I send pictures to the manufacturer and now I have to wait for a reaction. They were sold as tubeless ready. The hardest thing will be to determine what caused the crack. We'll see...
Next mountain adventure will be with my disc brake bike with alloy rims.

Over 2 years is a long time (you said recently) and I'll be surprised if you get anywhere. I was thinking they were a few weeks or months old. Hope you get something, I would think the 60% offer if you get it quite reasonable after the length of time you mention. They have only your word as to how well you look after them or the level of use.

Joost is not the OP, that's a different story.

trivial_poursuivant

Veronese68 wrote:

Trivial poursuivant wrote:

JoostG wrote:

Trivial poursuivant wrote:

How old are the wheels? You could threaten the shop with legal action if you can prove the wheels are not fit for purpose and the defect prevents use. Only thing that may stop this is if you can still use them as standard clinchers since they could argue that's how they were meant to be used. If they were sold as tubeless ready you may have a case.

The wheels are approx 2.5 years old and did between 5.000 - 7.500km (mostly in dry and flat conditions). I send pictures to the manufacturer and now I have to wait for a reaction. They were sold as tubeless ready. The hardest thing will be to determine what caused the crack. We'll see...
Next mountain adventure will be with my disc brake bike with alloy rims.

Over 2 years is a long time (you said recently) and I'll be surprised if you get anywhere. I was thinking they were a few weeks or months old. Hope you get something, I would think the 60% offer if you get it quite reasonable after the length of time you mention. They have only your word as to how well you look after them or the level of use.

Joost is not the OP, that's a different story.

Just realised, confused the f*** out of me that. Well my original question to the OP if he's still reading.

graememacd

I now have the wheels back so will be paying close attention to refitting the tyres. I'm hoping it was just a tyre/rim interface issue (possible user error!?) and nothing more sinister.