25mm tyres

Hippy's here! He can tell us which Continental to get.

:-)

I coat the inside of my tyres with a mixture of araldite and liquid cement and pump them to 180psi and I've never had a puncture in my life!

Isn't it annoying when science goes against natural instinct eh?

Thinner, harder tyres must be better, they just must :-)

Me TOO! Do we win a prize?

And me. But only because I can't get anything more than a 23 on the front of the langster.

i can't get more than a 23 on the front of the murthouse either

i for one was not aware of this trade off between high /low pressure and piercing/pinch flats

really interesting as i had been under the misapprehension that higher pressure = better

the other interesting point is the pressure and the likely surface you will encounter. i had noticed on really bad surface the bike constantly jitters, so maybe a lower pressure would be better for some of the piss poor roads here

dudes, are we seriously advocating low tyre pressure?

Pump em up to a bit more than it says on the sidewall. Its not rocket surgeons.

I should read more of the sheldon site

was interested to note that higher quality tyres benefit least from being overinflated.

Had also forgotten that front tyre should be 10% lower than rear, was generally runnin them at 5psi lower

it's good to learn new stuff, will also lower the pressure on road bike over winter as the surfaces get worse

can't imagine having a rear tyre lower than 100 psi but I am a lump and have 23 tyres

may look into trying something larger next time

Isn't it annoying when science goes against natural instinct eh?

And we haven't even started talking about weed yet. Or helmets ;-)

yea this thread turned up some useful info towards the end. i agree.

yet on page one there is some crap about pushing air away from spokes. If you push air away from spokes, what takes it's place? A vacuum? Water? Celestial Ether?

That was me. totally based on 'something I read on the interweb'. I remember reading that going from say 23mm to 20 mm was actually a bad thing aero dynamically speaking. For the same reason TT bikes have seat tubes that shield the rear wheel. I'm not going to pretend I truly understand it though, so I cant really defend it.

Wide tires only roll better at the same inflation pressure, but narrow tires can be inflated to higher pressures than wide tires.

This is exactly what Sheldon says.
Seems odd but comparisons of rolling resistance are often carried out at the same PSI, not the appropriate PSI for the tyres being tested WTF?.

was interested to note that higher quality tyres benefit least from being overinflated.

Its because better tyres have better flexual properties.

Had also forgotten that front tyre should be 10% lower than rear, was generally runnin them at 5psi lower

If your on smoothish road and run the same tyres front and rear. During winter I try and run my front lower still for better traction.

can't imagine having a rear tyre lower than 100 psi but I am a lump and have 23 tyres

Currently running my 42mm rear at 50 PSI, with about 45 PSI on the front. When the snow/ice comes I'll probably try to lower these slightly. I reckon these would roll real nice at this pressure if it was'nt for the mad tread/studds

I fully intend to run my 2,55" 29er tyres at less than 30 PSI (I'll have to try this out a bit though).

Go for Michelin kryolin carbon, 25mm, very fast, very good antipuncture, weight 240 grams

Ok, so was riding the beater today, not been on it for a while so the tyres were a little softer than usual, about 80-90 psi so thought I'd try it.

And my conclusion, it sucked. The ride was soft and sluggish, and I was very wary of any little bump in the road giving me a snakebite. I'l stick with my correctly inflated tyres and piece of mind.

Thanks.

@Donut! - that completely misses the point!

80-90psi is only an appropriate pressure if you've got 25mm tyres on.
105psi+ is an appropriate pressure for 23mm tyres. (80psi in a 23mm is going to be dreadful, I'd never advocate that!)

Correctly inflated, 25mm tyres run at lower pressures than 23mm tyres - this is the puncture protection advantage, among other things.

I didn't think that there are 25c tyres that designed for 80-90psi.

this kind of extremely geeky thread is still the very heart and the very best of the forum, great read.

though jersey you paraded your views around like an 8-year-old trying on his mom's underpants.

This had my inner bike nerd dribbling this morning. A chart that maps optimal tyre pressure against individual wheel load, for various tyre sizes. This'll be great for when I'm loading the mongrel's panniers.
http://www.vintagebicyclepress.com/images/TireDrop.pdf

Didn't take a pic of the 25mm bit but you get my gist...

I've got Pro2Races on my audaxesque bike, which have the same pressure guidelines as pictured above. If the weather's fine, and I know the road surfaces are good, I use 80f/85r; generally use 75f/80r; have gone as low as 70f/75r in the shittiest conditions.

They're comfortable, haven't pnctrd, and roll fast enough for a fucking heavy 25mm thing (it's the 25mm that's most like a touring tyre, in my experience).

With wishing to cause offence, most of you lot espousing the 'pump them up to max' rhetoric are fucking clueless, and I'm glad you're getting an uncomfortable and poorly handling ride. It's no wonder you're fucking crashing all the time.

[/too much coffee]

hangs head in shame

Loosing two arms?

...then having a strong urge for a wank?