Road tyres....are you led astray?

[Spoke101]

To the OP, do not let the other cynics get you down. I think you are on the right track.

 

I just so happen to have a set of Ultremos on a bike and had always considered them a bit mehh. Little did I know I was running them way to soft at 6 bar.

 

I pumped them to 9 bar before this morning's ride and I must say, the feedback is brilliant. I could feel every imperfection in the road so I can avoid them next time. Every time I strayed out of my lane I got a kick up the @rse as I crossed the white line. I rode over a coin and could tell that it was lying heads-up.

 

It was such a unique experience I don't think I can treat myself again. I'll go back to 6 bar and replace with some Contis when these are shot.

 

You not riding fast enough. You meant to just hit the tops of all the imperfections.   

[Jurgens Smit]

I haven't ever strayed away from gatorskins on my training wheels, and I doubt I will. I run them on a pair of k@k heavy alex rims pumped to around 7bar.

 

My racing setup however, am classic carbon 40 with gatorskin sprinter tubbies pumped to 9 bar back 8.5 front. I weigh 65kg. I like the way it rides and I haven't really played around with it.

 

I'll maybe get some better tubby tyres, but for me training wheels the gatorskin does the job 100%

[Andrew Steer]

Incredibly-random-unsubstantiated hub-opinions... are you led astray?

[Spoke101]

Hmm,

 

Road feedback is totally subjective. Feeling dead and or wooden has so many variables in it that you need to be specific. What wooden to you may be great to me and to a beginner may be revolutionary compared to what he previously had.

 

I am sure there are lots of great tyres out there - I have ridden plenty and can probably comment on some - but its all opinions mate.

 

Some guys will like some setups. Hence the comment about 11 bars on 21 mm. He believed that felt best and was the best setup. So there was no arguing as he believed that it was best, ipso facto, it was.

 

its what you believe and feel. 

 

Its like the new bike story. Or the clean bike story. Or the new tyres story. Or the placebo effect.

 

If you feel that it's better, it probably is. And you will do better because of it

 

Science doesn't have a check box for feelings and struggles to explain this but we all know its true.

 

So ride what you feel is the best and you will ride happy and probably well.

 

The reasons why I ride 10/11 bar in a 21mm are:

Can't fit anything bigger than a 23 in my frame and its so close a new on rubs the frame.

Racing elites comes with hitting the odd pothole/cateye because they don't really get called out.

21mm = reduced volume thus higher pressure is needed for pinch flat protection.

Yes at 60kg, 11bar and 80km/h I have hit a pothole in the bunch so hard it cracked the front rim, burst the rear tubbie, broke the bottle cages, and knocked the fork loose in the frame.

I can't afford to be shelling out 30-40k every race because someone couldn't be bothered to call "hole".

Finally I have tried lower pressures but I truly feel 11 bar roles faster at +50km/h.

[Spoke101]

well, first off buying that can handle 9 bar is all good and well. what most people forget is that what is actually important is what the rim that this tyre is fitted to is designed and made to handle. most rims are rated to 8 bar only.

pumping your tyre to 9 and beyond just causes damage as this pressure is not compatible.

been there paid the fees.

 

Another critical factor is the tyres TPI - thread per inch.

low = cheap and puncture prone - 60tpi

high = better puncture resistance (150-220 tpi) but costs more.

 

our roads are so full of glass that is is quite possible to cut a brand new tire up on your first ride.

My favs for training and racing (aiming for 150tpi and above):

Vredestein Fortezza Tricomp (if you can still get them)

Vredestein Senzo

Vittoria Rubino Pro3

Conti Gators

Agree with the Vittoria Rubino Pro3's great training tyre. Did many thousands of km's on them till the canvas was showing. I found the old Gators sidewall's where a soft spot (apparently the new ones are better). recently moved over to Spez Armadillos which might as well be tanks.

['Dale]

You not riding fast enough. You meant to just hit the tops of all the imperfections.

Hehehe

The Spoke has spoken

[Malpiet]

I love my Conti Ultra sports, did about 7000km's on them. Put Gatorskins on after that, the rear tyre bubbled after about 1000km, put the old ultra sport on the back. After 3 punctures on the front Gatorskins, I gave up and bought another set of Ultra sports. I don't have good luck with Gatorskins and they are so hard to change. I can see that they are heavier and stronger. ButI also love the grippiness of the Ultra sports. Maybe it's in my imagination...

 

when 25c craze hit i wanted to try out a set tosee if it really was what ppl were claiming and decided to experiment on a cheap set, the GP4000s tire i weighed was a mere 20 grams lighter than the Ultra sport but at double the price.

[Paul Ruinaard]

The reasons why I ride 10/11 bar in a 21mm are:

Can't fit anything bigger than a 23 in my frame and its so close a new on rubs the frame.

Racing elites comes with hitting the odd pothole/cateye because they don't really get called out.

21mm = reduced volume thus higher pressure is needed for pinch flat protection.

Yes at 60kg, 11bar and 80km/h I have hit a pothole in the bunch so hard it cracked the front rim, burst the rear tubbie, broke the bottle cages, and knocked the fork loose in the frame.

I can't afford to be shelling out 30-40k every race because someone couldn't be bothered to call "hole".

Finally I have tried lower pressures but I truly feel 11 bar roles faster at +50km/h.

As per the topic Sir, with all due respect, I think you are being lead astray. And I could not have asked for a better post than this to demonstrate what I was saying.

 

So i get your frame constraints and experiences. And they are all valid for you.

 

But the science says exactly the opposite. So how do I say this without looking like a twat and dissing you?

 

1.) The high pressure and narrow footprint of your tyres, plus the over inflation will transmit the shock much more effectively in to your frame and very likely created the issues you had with that accident. Chances are if you had a higher volume tyre at lower inflation it would have deformed and absorbed the shock much better and you wouldnt have cracked anything. Its simple - the more solid the object the better it transmits shock. Think about it.

 

2.) The feeling it rode faster. Totally subjective assessment when everything else points the other way. All the science. Conclusively and without doubt. 23 mm at lower pressure would be faster.

 

Plus it would have saved you a cracked frame etc.

 

However, having said that, and with lots of humility, no amount of science will convince you otherwise though, because this is what you feel. And in humans, feeling trump facts.

[Jurgens Smit]

 

As per the topic Sir, with all due respect, I think you are being lead astray. And I could not have asked for a better post than this to demonstrate what I was saying.

 

So i get your frame constraints and experiences. And they are all valid for you.

 

But the science says exactly the opposite. So how do I say this without looking like a twat and dissing you?

 

1.) The high pressure and narrow footprint of your tyres, plus the over inflation will transmit the shock much more effectively in to your frame and very likely created the issues you had with that accident. Chances are if you had a higher volume tyre at lower inflation it would have deformed and absorbed the shock much better and you wouldnt have cracked anything. Its simple - the more solid the object the better it transmits shock. Think about it.

 

2.) The feeling it rode faster. Totally subjective assessment when everything else points the other way. All the science. Conclusively and without doubt. 23 mm at lower pressure would be faster.

 

Plus it would have saved you a cracked frame etc.

 

However, having said that, and with lots of humility, no amount of science will convince you otherwise though, because this is what you feel. And in humans, feeling trump facts.

 

"Can't fit anything bigger than a 23 in my frame and its so close a new on rubs the frame."

 

So you're saying he should go 23 at lower pressure because it will roll faster (which = less watts) but the tire rubs the frame, causing resistance (which = more watts) so there is no real benefit to him?

 

Not trolling or trying to argue, just saying that he is making do with what he has available to him and 11bar works with his setup.

 

 

[Spinnekop]

I use Schwalbe One for both training and racing

And I'm happy

 

But ensure that your hoops are lekka light though.

Sub 1500 puppies for the win. 

Up here in Pretoria....that thing....Schwalbe One.....she does not exist. 

[Spoke101]

As per the topic Sir, with all due respect, I think you are being lead astray. And I could not have asked for a better post than this to demonstrate what I was saying.

 

So i get your frame constraints and experiences. And they are all valid for you.

 

But the science says exactly the opposite. So how do I say this without looking like a twat and dissing you?

 

1.) The high pressure and narrow footprint of your tyres, plus the over inflation will transmit the shock much more effectively in to your frame and very likely created the issues you had with that accident. Chances are if you had a higher volume tyre at lower inflation it would have deformed and absorbed the shock much better and you wouldnt have cracked anything. Its simple - the more solid the object the better it transmits shock. Think about it.

 

2.) The feeling it rode faster. Totally subjective assessment when everything else points the other way. All the science. Conclusively and without doubt. 23 mm at lower pressure would be faster.

 

Plus it would have saved you a cracked frame etc.

 

However, having said that, and with lots of humility, no amount of science will convince you otherwise though, because this is what you feel. And in humans, feeling trump facts.

Valid points, but I don't quite follow all of them?

 

1.) How does road vibration transmitted into the frame cause an someone to hit a pothole that appears a split second before you hit it as the rider in front of you bunny hops over it?

 

2.) Yes a larger volume tyre at lower pressure would have absorbed the shock better but this is not possible due to the frame constraints, further more the impact was so severe that the edge of the pothole compressed the tyre (at 11bar) so much so that it made contact with the carbon rim and thus cracked it. Unless I was riding a 30mm tyre I honestly don't think the outcome would have been any different.

 

3.) Yes a larger volume tyre at a lower pressure would have less rolling resistance but this is marginal and there are so many other ways to save watts in road racing. Now if it was a TT then that's a whole different story.

 

4.) There was never a cracked frame, it was the braking surface of the rim that cracked.

 

5.) The tyre in question has a minimum inflation pressure of 8 bar.

 

But hey, each to there own.

[Paul Ruinaard]

 

 

 

"Can't fit anything bigger than a 23 in my frame and its so close a new on rubs the frame."

 

So you're saying he should go 23 at lower pressure because it will roll faster (which = less watts) but the tire rubs the frame, causing resistance (which = more watts) so there is no real benefit to him?

 

Not trolling or trying to argue, just saying that he is making do with what he has available to him and 11bar works with his setup.

 

I think you didnt see me saying i get the constraints he has with his frame?

 

Re read the post.

 

Like i said - you will always get the people who swear otherwise, cause it works for them.

 

I can sit and google and post you a lot of links that will show you the physics of why at 11 bars a 21 mm tyre is way over inflated. 

 

The point is that 11 bar is totally the wrong pressure. Its way over inflated, and it probably caused some of his issues wrt the cracked frame.

 

And I am just trying to help and respectfully suggest he rethinks the logic he used to reach that conclusion.

 

Its like when your bud tells you he is wanting to do something that you know is absolutely wrong but he's convinced otherwise. Someone has to tell him that he's wrong in a gentle way. But if you do he may tell you that you are a tosser?

 

Here is just one link from a quick search- this is from the Cervelo team testing riding on cobbles in Belgium (square edgeed) and their findings:

 

http://rebrn.com/re/for-all-of-you-folks-trying-to-give-out-advice-on-tire-pressures-1917421/

[porqui]

To OP

 

Here you go

 

Uncle Sheldon Brown

 

http://sheldonbrown.com/wheels.html

 

and

 

http://sheldonbrown.com/tires.html

 

Digest it !!

 

(But I see OP has not been back - Rouxtjie must have dropped him a line)

[Jurgens Smit]

I think you didnt see me saying i get the constraints he has with his frame?

 

Re read the post.

 

Like i said - you will always get the people who swear otherwise, cause it works for them.

 

I can sit and google and post you a lot of links that will show you the physics of why at 11 bars a 21 mm tyre is way over inflated. 

 

The point is that 11 bar is totally the wrong pressure. Its way over inflated, and it probably caused some of his issues wrt the cracked frame.

 

And I am just trying to help and respectfully suggest he rethinks the logic he used to reach that conclusion.

 

Its like when your bud tells you he is wanting to do something that you know is absolutely wrong but he's convinced otherwise. Someone has to tell him that he's wrong in a gentle way. But if you do he may tell you that you are a tosser?

 

Here is just one link from a quick search- this is from the Cervelo team testing riding on cobbles in Belgium (square edgeed) and their findings:

 

http://rebrn.com/re/for-all-of-you-folks-trying-to-give-out-advice-on-tire-pressures-1917421/

Sorry bud, honestly did not even see that, but I do get what you're saying.

 

My post was entirely based on you sounding like a tosser

 

I work in IT and honestly we have the same **** every day, there is the right way recommended and backed by research and then a oke does the complete opposite, but hey it works for him.

 

However I did a google search to find optimal 21mm tire pressures and couldn't really find anything, all I could find only starts from 23 and up. So what would be the correct pressure

[porqui]

Jurgens to find correct pressure go to manufacturer site.

[Paul Ruinaard]

Sorry bud, honestly did not even see that, but I do get what you're saying.

 

My post was entirely based on you sounding like a tosser

 

I work in IT and honestly we have the same **** every day, there is the right way recommended and backed by research and then a oke does the complete opposite, but hey it works for him.

 

However I did a google search to find optimal 21mm tire pressures and couldn't really find anything, all I could find only starts from 23 and up. So what would be the correct pressure

No offense. I work in IT as well and often have the same experience.

 

Like a SQL DBA that believes best practices are reference guides and suggestions :-).

 

Like it was said - start at the manufacturer's site. Rim widths also need to be taken into account. But i assume he is using very narrow rims already.

 

Actually,  Mr Spoke 101 -  a frame that can only take 21mm - that has sent all sorts of questions off in my mind as well. What sort of frame and rim combo and what is the I/d of the rim? I would be interested in seeing that as well. Does Not compute.

 

But there is so much more to this than pressure and puncture/square edge resilience - handling etc would be a nightmare, even if slightly wet on an overinflated tire.