Author Topic: To tubeless or not to tubeless  (Read 15420 times)

quixoticgeek

  • Mostly Harmless
To tubeless or not to tubeless
« on: September 30, 2018, 10:43:59 am »

In April I put a pair of Conti GP 4000s ii 28mm tyres on, I ran them for just shy of 5000km, without a single flat. Even with the broken glass paving of Dutch cycle paths, Belgian "roads", French Pavé, and some off roading.

So just before my planned tour I put a new set of the same tyres on, loaded the bike with a very light touring setup, and headed for Hell.

I had 2 punctures in the first 30km. Which set the precedent. Over the next 600km I had 8 flats. I had to write off an outer as I couldn't fish out the remaining bit of scandi flint, I put on a specialised All Condition Armadillo on the back. This got me the final 800km to Hell without any more flats, but when I got back to Denmark, the Armadillo had it's first flat, and at the same time I noticed a side wall failure on the front conti, with the tube sticking out. All in all I wrote off 2 gp4000s in under 1500km.

Given the faff of fixing flats, I'm seriously considering going tubeless. But I have reservations[1]. Primarily I'm looking at what happened to Bjorn in this years TCR[2], if I'm in the middle of nowhere and can't magic up a compressor, am I looking at basically having to fall back to a normal clincher with a tube? If I've gone for a tubeless rim, can I put a normal clincher in there as a get me moving again fix?

I'm looking at things from an ultra-racing point of view. What failure modes should I be aware of before deciding on tubeless?

Any reason I shouldn't go tubeless for this sort of use case? If I don't go tubeless, what fast clinchers would people suggest for racing? I'm kinda losing faith in the gp4000s.

J

[1] Yes this is yet another geek ponders failure modes thread
[2] For those who didn't follow, Bjorn had big failure on his rear tyre at CP3, he had a new outer, he managed to save the sealant from the original tyre, but then had issues getting the new to fit, until he managed to find a compressor by magic from the caretaker of a hotel.
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: To tubeless or not to tubeless
« Reply #1 on: September 30, 2018, 11:13:42 am »
new tyres are usually much softer than ones that are even six or nine months old.   New tyres grip better but they cut up and puncture very much more easily than older ones, especially when it is wet.  BITD it was SOP to mature tubs and I still do this with HPs; I prefer a bit less grip to lots of punctures.

 Hereabouts I see a lot of people with flats in the winter and most usually they are running new contis and they have succumbed to a flint or similar. I usually stop and give them a hand if they need it and I usually test the tyre with my thumbnail to see how soft it is. 'Pretty soft' is the normal answer. Flints vary by type and quantity depending on where you are; in some places there are lots, in other places not so much.

  After a year or eighteen months the GP4000 is normally so hard that grip is compromised; one of my chums will bin them at this point whether they are badly worn or not.

GP4000 is a racing/training tyre, not a touring tyre anyway.   Note that if you are getting sidewall problems then the tyres are not strong enough for your service conditions; tubeless or not it makes no difference, the tyre is wrecked. Contis have a special problem which is that they have (and need) a chafer ply that stops the rim from gouging the sidewall.  However the chafer tends to fall apart or come unglued from the rest of the tyre. I have seen quite a few tyres fail because the tyre has been on and off the rim a few times and the chafer has been folded over or has fallen apart; the next thing is that the sidewall fails just above the rim.  This process is very greatly speeded up if the rim has ever hit the road (eg running to a halt on a flat tyre or even resting the bare rim on a stony surface); even tiny burrs on the rim edges can cut the tyre fabric in time.

Tubeless tyres vary in their fit on the rim and how easy they are to deal with.  I don't see that for my riding they offer any real advantage, but they come with a whole host of potential problems.  I can't remember when I last had more than two punctures in a year's riding, yet I carry patches and booting fabric wherever I go, and a spare tube if it is more than a few miles.  I think I'd need to carry more stuff if I ran tubeless and I'd be less certain of fixing any major roadside problem well enough to be able to continue.

cheers

Re: To tubeless or not to tubeless
« Reply #2 on: September 30, 2018, 11:15:29 am »
Non-tubeless:  You have to carry tubes and pump. You'll almost certainly have to use it a few times during the life of the tyre. Sometimes this may be in the pissing rain, with hands so cold you can't move your fingers.

Tubeless: You have to carry tubes and a pump, just like non-tubeless. If you get a gash you'll have to use a boot, just like non-tubeless. But you probably won't have to do either of these things to the extent that you do with non-tubeless. If you get a puncture that won't seal you put a tube in. You don't need a compressor.

Yes, you can use non-tubeless tyres on TL ready rims.

LittleWheelsandBig

  • Whimsy Rider
Re: To tubeless or not to tubeless
« Reply #3 on: September 30, 2018, 01:31:02 pm »
Aging vulcanised tyres is somewhat meaningless. Handmade tyres can benefit from a little extra time to bond tread and casing. http://www.cxmagazine.com/buying-tubulars-tires-early-aging-process-explained

I've never been a big fan of aging tyres for puncture resistance. Pick the tyre (and tyre construction) for the puncture resistance you want from the beginning. Factories can tailor rubber characteristics for whatever performance is desired straight away. Harder rubber means less grip in wet corners, which can be a significant problem (I've broken too many bones). I tend to agree with Brandt that "aging tyres is a good thing" came from shops needing to move old stock.
Wheel meet again, don't know where, don't know when...

Re: To tubeless or not to tubeless
« Reply #4 on: September 30, 2018, 02:51:46 pm »
Pick the tyre (and tyre construction) for the puncture resistance you want from the beginning.

Quoted for truth.

Don't expect race tyres to be tough. Don't expect touring tyres to be nimble and fun.

If you want the fun of race tyres, going tubeless mitigates the downsides to a certain degree. In fact, what it means is that all the maintenance time gets shunted to a time and place of your choosing (fitment and sealant top-up), rather than at the roadside. If you get a catastrophic failure that a tube won't solve then you are in the same position as were it to happen with a conventional tyre.

Phil W

Re: To tubeless or not to tubeless
« Reply #5 on: September 30, 2018, 02:56:43 pm »
Mavic UST road tubeless can be inflated with an ordinary pump you carry on the bike. To check this wasn't luck I tried it several times all times they inflated with ease.

If on a long ultra race then you can always carry a small container of sealant with a nozzle applicator to fill through valve.

If you get a hole that won't seal then flexible superglue applied from outside can cure. No need to unmount the tyre bead from the rim.

Without sealant they will still inflate. They will just lose air over a period of hours. My sealant dried out over the heatwave which I disvovered with a puncture in one tyre. So i topped that up and it sealed fine. I forget to top up the front (as well)  so that gradually went soft during my ride.  I found I would get 100km between reinflating, so not the end of the world.

Re: To tubeless or not to tubeless
« Reply #6 on: September 30, 2018, 03:49:14 pm »
CO2 cylinders are sometimes required to (re)inflate a tubeless tyre. I’ve never had a problem with it affecting latex based sealants but have switched to Finish Line “Kevlar” CO2 friendly sealant in my tubeless tyres just in case. This also doesn’t dry out and doesn’t need regular replacement. The only puncture I’m aware of having was when I rode over a broken Kilner jar (or whatever the French equivalent is) and no tyre would have survived the gash unscathed. I patched it from inside and fitted a tube. I’m no mile eater, but I was out of work this summer and rode 2-300km a week, with no punctures which was remarkable for me. Unlike Brucey I’d regularly have 4 or 5 punctures every summer with tubed tyres, including GP4000’s, which I found bastard hard to fit and remove from the CXP rims I had. 
We are making a New World (Paul Nash, 1918)

Re: To tubeless or not to tubeless
« Reply #7 on: September 30, 2018, 06:44:09 pm »
Aging vulcanised tyres is somewhat meaningless....

Not in my experience.  A large part of the cost of tyres is 'mould time' and the way they reduce that is to reduce the time at temperature in the mould.  The vulcanising reaction is incomplete and continues outside the mould, for an appreciable length of time. Probably it never stops completely  for the entire life of the tyre.

I've ridden enough miles to know the difference for sure; I've ridden hundreds or even thousands of miles alongside folk running exactly the same tyres at the same pressure as mine, only mine are six months or a year old and theirs are new. They have had lots of punctures and I have had virtually none.

cheers



LittleWheelsandBig

  • Whimsy Rider
Re: To tubeless or not to tubeless
« Reply #8 on: September 30, 2018, 06:54:53 pm »
OK but tyre manufacturers who make both vulcanised and handmade tyres disagree with you.
Wheel meet again, don't know where, don't know when...

zigzag

  • unfuckwithable
Re: To tubeless or not to tubeless
« Reply #9 on: September 30, 2018, 07:49:58 pm »
there is a long thread on here about tubeless tyres, worth a read if you have time. tubeless works better with higher volume and lower pressure tyres. i'd say 30mm tyre with 70psi are the ballpark figures where the sealant starts to work reliably (the numbers are made up by me from my own experience/judgement). while tubeless is an obvious choice for mtb tyres, it doesn't always work for the road setup (yet).

quixoticgeek

  • Mostly Harmless
Re: To tubeless or not to tubeless
« Reply #10 on: September 30, 2018, 09:18:13 pm »

GP4000 is a racing/training tyre, not a touring tyre anyway.   

How does that square when racing with what some would consider a very light touring rig?

Whilst the trip was a tour/holiday, I was using it as a low stress opportunity to test out kit, techniques, approaches.

Now I'm back, I now need to focus on training for my next race in May.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: To tubeless or not to tubeless
« Reply #11 on: September 30, 2018, 10:49:32 pm »
The difficulties of tubeless are often overstated and can be addressed.

Find a rim/Tyre combination that works - Kinlin and Schwalbe Ones don’t seem to need more than a track pump for example. Carry Tyre works, superglue and a mini pump, and a small bottle of sealant on a long tour. You could even carry a basic tube repair set up too for insurance.

You can fit non tubeless three to tubeless ready rims, but some are excessively tight, e.g. Challenge Paris Roubaix Open don’t go on to Kinlin rims with my thumbs. Otherwise, many others are fine including the Challenge Almanzo, which is a bit bigger.

Re: To tubeless or not to tubeless
« Reply #12 on: September 30, 2018, 11:07:59 pm »

GP4000 is a racing/training tyre, not a touring tyre anyway.   

How does that square when racing with what some would consider a very light touring rig?


a 'light touring load' is like having a bike that weighs two or three times the normal weight sat on the tyres.  As explained in another recent thread, weight on the bike puts far higher dynamic  loads into the wheels and tyres than the same weight in the rider; the reason is that the latter is 'sprung weight' (i.e. it is not coupled to the bike rigidly) and the former is unsprung weight, that smashes the bike into every bump in the road whether you like it or not. Stiff frames and stiff forks don't help either.

If the chafer ply was damaged or wasn't positioned correctly I can see how a light-built tyre could fail in a relatively short distance anyway. With a load on the bike (even a fairly light one) the tyre will just see more, bigger loads than normal.

It is normal to use stronger tyres for touring on; there are several reasons for this, amongst which is the extra loading, the negligible benefits of 'faster tyres' as well as the extra PITA factor in sourcing new tyres in unfamiliar (possibly remote) territory.

The other thing is that a tyre failure in the sidewall usually doesn't happen instantly; a failing tyre usually goes out of shape before it fails completely. If you are doing day rides from home then you ought to spot the damage when you check your bike over before any given day's ride. If the tyre is not out of shape in the morning, the chances are good that it won't fail catastrophically on that day's ride.  If you are going touring for ten days, you arguably need to be ten times surer of your tyres.

If those were good tyres for touring on, that would imply that you could use much lighter-built tyres for unladen one-day events.  What tyres would they be, I wonder?

cheers

quixoticgeek

  • Mostly Harmless
Re: To tubeless or not to tubeless
« Reply #13 on: October 01, 2018, 09:01:49 pm »

a 'light touring load' is like having a bike that weighs two or three times the normal weight sat on the tyres.  As explained in another recent thread, weight on the bike puts far higher dynamic  loads into the wheels and tyres than the same weight in the rider; the reason is that the latter is 'sprung weight' (i.e. it is not coupled to the bike rigidly) and the former is unsprung weight, that smashes the bike into every bump in the road whether you like it or not. Stiff frames and stiff forks don't help either.

I'm not sure I follow. How is adding 5kg of luggage to a 12kg bike equivalent to riding a 24-36kg bike?

Quote

It is normal to use stronger tyres for touring on; there are several reasons for this, amongst which is the extra loading, the negligible benefits of 'faster tyres' as well as the extra PITA factor in sourcing new tyres in unfamiliar (possibly remote) territory.

When does a race become a tour?

Quote

The other thing is that a tyre failure in the sidewall usually doesn't happen instantly; a failing tyre usually goes out of shape before it fails completely. If you are doing day rides from home then you ought to spot the damage when you check your bike over before any given day's ride. If the tyre is not out of shape in the morning, the chances are good that it won't fail catastrophically on that day's ride.  If you are going touring for ten days, you arguably need to be ten times surer of your tyres.

Does that apply when doing multiple 100km per day? What about going racing for 10 days?

Quote

If those were good tyres for touring on, that would imply that you could use much lighter-built tyres for unladen one-day events.  What tyres would they be, I wonder?

I've no idea, this isn't the sort of bike you would think to ride, what with the lack of bar end shifters, lack of drum breaks, etc...

I used the same tyres that James used for the TCR.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: To tubeless or not to tubeless
« Reply #14 on: October 01, 2018, 10:09:12 pm »
if you put 5kg over one wheel, that beats the tyre up something rotten IME, worse than (say) 10kg more rider weight, probably.

Philosophical questions aside, it is all balance of the availability of new tyres, the real speed/comfort benefits of using a particular tyre  and the chances/consequences of failure. This isn't an exact science, and different folk will come up with different solutions that work well enough for them.

BTW you don't know what I'd ride in any given circumstance; I have quite a few (very) different bikes. 

cheers


Re: To tubeless or not to tubeless
« Reply #15 on: October 02, 2018, 07:05:11 am »
I share your uncertainty as to what is best but, unfortunately, no-one can give us the answer. 

I've only ever had two disastrous tyre failures that led to me replacing the tyre.  The first was with tubeless in TCR and the second a tubed tyre in IndyPac.

Tyre failure is a rare event so no-one's experience is representative enough to draw conclusions from, and the data that you would need to make a decision is not available.  Your (semi-informed) guess is as good as anyone elses!

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: To tubeless or not to tubeless
« Reply #16 on: October 02, 2018, 09:17:42 am »
A year ago I had a chat with a bloke in his sixties who was enthusing about the Kinesis Tripster he'd bought himself as a retirement present. In addition to its titanium loveliness, he was very keen on the benefits of the tubeless tyres. "The best thing about them," he said, "is that you can't get a pinch puncture, because there's no tube to pinch. Mind you," he added, "in fifty years cycling I've only ever had one pinch puncture, so I suppose it's not really that much of a benefit."

Which I think illustrates Frank's point; the benefits and disadvantages you experience will be a selection of the entire range of benefits and disadvantages, depending on your present experiences with tubed tyres.
sideways bounding monkey lounging under fruit tree

Re: To tubeless or not to tubeless
« Reply #17 on: October 02, 2018, 12:37:12 pm »
There is an easy answer to this question. Don't bother to torture your brain and suffer sleepless nights. Your technical choices and mine for our bikes are always diametrically opposed. I am using tubes. Nuff said??

Re: To tubeless or not to tubeless
« Reply #18 on: October 02, 2018, 01:16:50 pm »
OK but tyre manufacturers who make both vulcanised and handmade tyres disagree with you.

the effect is usually much larger with the latter type for sure but that is not to say that it is irrelevant with vulcanised tyres; it can be just as important. 

BTW I take anything and everything that tyre manufacturers say with a king-sized pinch of salt. IME they mostly talk a load of hype, nonsense and complete bullsquirt.  Very few of them seem to have adequate QC procedures, judging by the number of new tyres that are NFG.

 Quite recently about half the pro peloton defected from one tyre manufacturer to another, when the previous favourite manufacturer of wet weather tyres managed to supply tyres that had next to nothing in the way of wet weather grip. They seemingly  had no idea that they had managed to make duff tyres and less idea why they had done it (or presumably how to cure it, either).

cheers

Re: To tubeless or not to tubeless
« Reply #19 on: October 02, 2018, 03:53:03 pm »
if you put 5kg over one wheel, that beats the tyre up something rotten IME, worse than (say) 10kg more rider weight, probably.

cheers

Really?  10kg extra rider would need a perfect 50/50 split to only load up a tyre by 5kg. So IMO 10kg extra rider is worse for the most heavily loaded tyre. Since a typical weight distribution would be say 60/40 rear/front, 10kg rider adds 6kg to the rear and 4kg to the front.

https://www.vernier.com/innovate/investigating-weight-distribution-on-a-bicycle/
We are making a New World (Paul Nash, 1918)

Re: To tubeless or not to tubeless
« Reply #20 on: October 02, 2018, 03:56:24 pm »
Quite recently about half the pro peloton defected from one tyre manufacturer to another, when the previous favourite manufacturer of wet weather tyres managed to supply tyres that had next to nothing in the way of wet weather grip. They seemingly  had no idea that they had managed to make duff tyres and less idea why they had done it (or presumably how to cure it, either).

cheers

Really? How recently?

Re: To tubeless or not to tubeless
« Reply #21 on: October 02, 2018, 04:35:28 pm »
if you put 5kg over one wheel, that beats the tyre up something rotten IME, worse than (say) 10kg more rider weight, probably.

cheers

Really?  10kg extra rider would need a perfect 50/50 split to only load up a tyre by 5kg. So IMO 10kg extra rider is worse for the most heavily loaded tyre. Since a typical weight distribution would be say 60/40 rear/front, 10kg rider adds 6kg to the rear and 4kg to the front.

https://www.vernier.com/innovate/investigating-weight-distribution-on-a-bicycle/

the difference occurs because the weight strapped to the bike is pretty much unsprung weight and the weight of the rider is pretty much sprung weight.  Unsprung weight is far more harmful, to the tyres especially.

cheers

Re: To tubeless or not to tubeless
« Reply #22 on: October 02, 2018, 04:39:49 pm »
Quite recently about half the pro peloton defected from one tyre manufacturer to another, when the previous favourite manufacturer of wet weather tyres managed to supply tyres that had next to nothing in the way of wet weather grip. They seemingly  had no idea that they had managed to make duff tyres and less idea why they had done it (or presumably how to cure it, either).

cheers

Really? How recently?

within the last year or two I think.  Yanto Barker was on about it during the live commentary of the ToB a few weeks ago.  Doubtless there will be others who can clarify the details.

cheers

Re: To tubeless or not to tubeless
« Reply #23 on: October 02, 2018, 04:59:54 pm »
Quite recently about half the pro peloton defected from one tyre manufacturer to another, when the previous favourite manufacturer of wet weather tyres managed to supply tyres that had next to nothing in the way of wet weather grip. They seemingly  had no idea that they had managed to make duff tyres and less idea why they had done it (or presumably how to cure it, either).

cheers

Really? How recently?

within the last year or two I think.  Yanto Barker was on about it during the live commentary of the ToB a few weeks ago.  Doubtless there will be others who can clarify the details.

cheers

I can't think that it can be recent and accurate. Essentially for the last couple of years Continental are the only manufacturer that has got anywhere near close to supplying "half the peloton" (assuming we are talking WT teams here). They supplied 9 teams last year and 7 this year, out of 22 WT teams. The others are supplied by a mishmash of others.

The only thing I have heard with regards to wet weather was Team Sky dropping Veloflex because the wet performance wasn't good.

Re: To tubeless or not to tubeless
« Reply #24 on: October 02, 2018, 05:41:53 pm »
Frankly, they should exercise a little caution and slow down when it rains