[nadsta]

Running (Specialized) RovalCL50 wheels with Enve SES TLR 25 tyres (75psi front). Last Sunday I hit a series of small potholes through Epsom, (I’d say I’ve straight-lined worse in the past with no worries), front went bang (tyre didn’t puncture though) and I went down hard. 

When I picked up the bike the front tyre was inside out. This tyre’s done 4.5k, is in roadworthy condition, no repairs/tyre boots/plugs. New sealant and inspected recently. The Enve tyre and Roval rim combination makes fitting fairly easy using a single lever or even just strong thumbs and a good push.  Maybe that’s a red flag but hearing horror stories about tricky GP5000’s from many I thought I was onto a good thing. Needs a compressor or tubless inflator to seal. Tyre doesn’t need a hookless rim. I just don’t understand how it could have come off if rim & tyre are in spec.

Lots of road rash, trashed kit, cracked frame and smashed levers etc. Wheel actually looks like it might survive despite the fact I was just rolling on the carbon momentarily (which sounded horrible) before going down. 

Thankfully I didn’t take anyone else out, didn’t hit the kerb or get collected by a car. I have bike insurance, I have other bikes and after a couple of weeks of healing I’ll be hopefully ok to ride. But it could have been very different.

So far some have just blamed the fact it’s tubeless. If any one has any constructive thoughts beyond this I’d love to hear them.  My take is that this is a rim/tyre design or manufacturing failure and I should take it up with the manufacturers. 

However the fact that Specialized has abandoned tubeless on the SL7 is not lost on me.

Topic

[ENVE]

Hi Nadsta – it’s never good

Hi Nadsta – it’s never good seeing images like this and we’d like to get more information. Can you email jake@enve.com so we can be in touch? Thank you. 

[Recoveryride]

I think tubeless for off-road

I think tubeless for off-road use is fairly mature technology and now works pretty well. I certainly wouldn’t go back to tubes for gravel/MTB and I’m not aware of any horror stories like this one. The lower tyre pressures and higher air volumes also means that, frankly, it works better. It’s a pretty settled debate, I think.

On road, though, the jury is still out, IMO.

Yes, punctures are less likely, the ride quality is better, and in theory they are minutely faster, but the much higher pressures and lower air volumes used on road present a number of problems:

1. it is hard for the sealant actually to work at over c. 70 psi.
2. Even if it does work, the high pressure and small air volume in the tyre can mean that by the time it does, you still effectively have a flat, and when you try to reinflate, the hole unseals again.
3. The mechanics of holding the tyre on the rim at a higher pressure, especially in case of a flat/impact are more complex – as this thread bears out.
4. Addressing point 3 effectively often means a tyre which is very hard to fit, and almost impossible to add a tube to in case of emergency [exhibit 1, Conti GP5000 TL]

These problems aren’t insurmountable and won’t be an issue for everyone, but it’s good to be aware of them.

I’m honestly agnostic on the tubeless debate for road, but I’m tending towards tubed, if only because of the remote chance of catastrophic incidents like the one described in this thread.

[Chris Hayes]

Horror show photos.  I used

Horror show photos.  I used to ride a motorbike and was conscious that all the grip you have cornering is tranferred through a few square inches of tread – an autumn leaf’s worth, if you like.  Road bikes tyre surface area contact is a fraction of this and whilst we mostly travel at lower speeds, lycra isn’t much protection against stone-chipped asphalt. 

I think the most plausible explanation is recoveryride’s below, that the tyre caught the edge or lip of a pothole, distorted, letting the air out, and then de-rimmed.  Wow. Just wow. 

I wonder if running tyres at lower pressures could contribute to this?  I’m an 85psi man myself, a lot less than the 140psi one of my German mates insists on squeezing into his Vittorias, but I’m inclined to think that higher pressure tyres might distort less and so be less prone to twisting.

[wtjs]

tubeless tyres in my

tubeless tyres in my experience should do the exact same

They are tubeless tyres, which came with the bike, but I have no intention of using them tubeless. I fixed a slow puncture on the front this morning- I counted the patches on the original tube- 12

[Anonymous]

Jeez! I did not expect that!

Jeez! I did not expect that! It’s literally nearly done a 180 on the rim!

That’s not just a burp or a simple deflation on impact. That looks like an incompatibility issue that’s happened in the 1-in-a-million type scenario. A perfect storm if you will.

Thinking about it, tyres that are meant for hookless applications are supposed to be stronger at the bead. Purely because they don’t have the hook to hold them on.

I’m wondering if hitting a bump at the bottom of the wheel has allowed, momentarily, for the tyre to slip in to the central channel which has then allowed the tyre to become baggy/loose at the top and pop over the edge?

Like Chris says though, the GP5000 is a fantastic tyre and in my opinion is able to hide the sins of a bad tubeless design.

[nadsta]

HI Chris, thanks for you

HI Chris, thanks for you input.  The Rovals are hooked, the Enve tyres claim both hooked and hookless compatibility. Enve’s tubeless wheels appear to be hookless so one would assume their tyres are mainly developed using that standard.  I haven’t much enjoyed being a beta tester!

[nadsta]

eek

eek

[Chris Hayes]

Thanks for posting this,

Thanks for posting this, Nadsta.  Glad that you’ve both survived the experience and retained a healthy and philosophical attitude.  Sharing experiences like this makes us all safer.

​I’ve been warned by my LBS about the compatibility of certain tubeless tyres and rims following difficulty in getting a good seal. Apparently this derives from shape and dimensions of the rim hook versus the tyre bead. I guess that hookless rims compound this.  It’s certainly one to look out for.

I tend to use GP5000s for everything apart from Mavic wheels for exactly this reason. Mavic, for some unknown reason, wouldn’t share their data with Continental when developing their tubeless rims and so advise only using Mavic tyres. Just to be contrary, I use Hutchinsons who make tyres for Mavic so they don’t make any more money from me! 

[nadsta]

Old is relative! Yes it’s a

Old is relative! Yes it’s a great sound as the tyre seats, but tubeless tyres in my experience should do the exact same. 

[nadsta]

Thanks for sharing your

Thanks for sharing your experience Sparrowlegs.  I tried Spesh’s 2bliss 26s which were fine to get on and inflate but after 3 total tyre failures due to puctures within about 1000km I gave up and tried the Enve’s which have been great. I will try the tyre on another rim when I get the bike back (in for insurance assessment).

To answer your q’s, I fitted the Enve tyres last September, I’m 73kg, we were on rolling roads 3 up on a very slight descent, no heavy braking and I don’t think temperature would have been a factor.  Thanks for your injury advice. A week later and the road rash has just started to heal, as mentioned I’ve been v lucky.

Sounds like Roval haven’t been able to design a satisfactory tubeless road rim, I’ll get in touch with them!

[nadsta]

Recoveryride wrote:

there have been concerns about Rovals not retaining a tubeless tyre in the event of a sudden loss of pressure or – as seems likely in your case – a burp.

Thanks, I hadn’t thought of Weight weenies and poking around there does show issues with Rovals retaining a tyre in the bead lock. I will pursue it with them.  Also I think you may be right when you speculate that a burp after striking the pothole partially unseated the tyre before the full failure, at least that was my recollection at the time-a bump, some loss of control but well within my ability to correct, followed by a bang as the tyre rolled off. 

[wtjs]

You’re really talking me into

You’re really talking me into going tubeless! I have the appropriate wheels which came with my fairly new gravel bike but, as an old fuddy-duddy, I have confined myself to enjoying the satisfying noise as the tube pushes the tyres onto the ‘ramps’, or whatever they’re called.

[Anonymous]

First off, I’m glad your ok

First off, I’m glad your ok other than the road rash. Like you said it could have been a lot worse.

I have experience with the Roval, I had some CLX 50 and due to a pretty miserable tubeless experience I sold them. I’d constantly find the tyres unseated and sealant everywhere. The best tyres I used on those wheels were the GP5000. Mainly because they were so tight. They were the only ones I felt confident going on longer rides on and they stayed up all the time, but only at the higher end of the pressure gauge  

The shape of the tubeless ridge doesn’t hold the tyre on like Hunts or Scribe (or any other tubeless rim for that matter). I found that after a tyre had been fitted to them it was hard to get it to seal on any other wheels. 

4.5k sounds a lot but if it’s done in one year then that’s ok. How long have the tyres been fitted? How heavy are you? Had you been braking quite a lot beforehand, the rim/tyre might have had a lot of heat in it?

Those tyres are designed to work with Enve hookless rims and it’s what stopped me from buying them, even though they say they work with hooked rims.

It sounds like the tyre may have lost some pressure at some point and then re-seated but blown past the rim outer. I also think the profile of where the tyre interfaces with the hook of the rim might not fully compatible. The Roval rims are a very old design and in my opinion a very poor tubeless design. Many forum posts will back this up.

If it still intact I’d try the tyre on another rim to see what its integrity is like. After that, take it up with the manufacturers.

Also, after a crash many years ago while I was in A&E the Dr said salt baths is the best thing. Loads of table salt in a bath. It doesn’t sting at all and speeded up the skin repair.

Good luck and quick recovery. 

[Recoveryride]

From what you describe, I

From what you describe, I would speculate that the tyre has caught on the side edge of a pothole and gravity/momentum/the impact has pulled it off the rim.

There are a few threads on, or connected to, this on weightweenies. I haven’t been through them all, but from my brief scan, and what I can remember, there have been concerns about Rovals not retaining a tubeless tyre in the event of a sudden loss of pressure or – as seems likely in your case – a burp. Somebody posted a diagram highlighting a possible issue although IDK if it was of your model.

It’s interesting, as you note, that the newer Roval wheels are explicitly not tubeless compatible, despite having a rim bed that looks pretty much identical to the older ones, so maybe this is something Roval is aware of. That said, if it was/is a known safety issue, I’d like to think they’d recall/issue a safety notice.

I would definitely pursue it; like you said, this could have been very nasty indeed.

Best wishes for a speedy recovery.

[Author]

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