Tyre Pressures

[MrJamie]

like I said earlier - that is only true if you are riding on a 100% smooth surface, like a track, or if you happen to be riding on ballroom floor. On real roads with varied surfaces, a rock-hard tyre will almost certainly be slower than the same tyre at the correct pressure.

What would be the correct pressure for me?

Most of my 18stone+ weight is sat fairly upright over the back wheel, with a saddlebag that has been known to hold tools plus a 12 pack of beer (or similar heavyish shopping) so I was guessing that i should be nearer the max end of the psi scale for mostly road riding. Also I read that because the M+ puncture protection strip is central to the tyre tread, its important to keep well inflated so they roll on the strip.

As you say though, a cartwheel is a pretty accurate description in terms of shock absorbtion, with alu frame my lower back always gets really annoyed with me pumping the pressures up. About 60-65 feels more like a comfortable compromise.

 

[black'n'yellow]

from what you've said, I'm guessing 65-70. Bear in mind that nobody buys Marathons for their 'supple' ride qualities..

 

[Recycler]

you kidding..?? 38c Marathon Plus at 85psi will ride like a cartwheel...

Cartwheel or not, I'm with ianrauk on this. I ride my Marathons at the top end of the range. It may be a fraction harsher, but it is certainly quicker.

 

[black'n'yellow]

Cartwheel or not, I'm with ianrauk on this. I ride my Marathons at the top end of the range. It may be a fraction harsher, but it is certainly quicker.

interesting - how are you quantifying that..?

 

[Recycler]

interesting - how are you quantifying that..?

To be honest, I've not done a proper test to check it out. To do so would mean doing several rides at different pressures, and then trying to eliminate all the other variables.....life's too short.

I do know that when I was trying to push a wheelbarrow around the garden the other day it was a lot easier when I inflated it properly.

But, it definitely feels faster on the bike and logic alone tells me that it is likely to be.

This is not intended as a tit-for-tat response but, have you been able to quantify your earlier rollling versus bouncing comments in #9 ?

 

[Psycolist]

60psi is definitely 'between 50-85psi' - so I'm gonna say yes. Fine tuning of that pressure should be down to you - nobody else.

Wot he said

 

[Peteaud]

Run my 35's on the hybrid at 80 and never had a problem. Same as the wifes bike, 32's on 80psi.

 

[black'n'yellow]

This is not intended as a tit-for-tat response but, have you been able to quantify your earlier rollling versus bouncing comments in #9 ?

it's not down to me to quantify it, because it's not my theory. Plenty of studies and articles available to read if you google it...

 

[black'n'yellow]

Run my 35's on the hybrid at 80 and never had a problem. Same as the wifes bike, 32's on 80psi.

I bang my head against a wall several times a day and I've never had a problem. Doesn't make it the right thing to do...

 

[Boris Bajic]

I think the OP was looking for impartial advice, so I will help where others seem unable or unwilling to oblige.

I run totally different tyres from a totally different manufacturer.

I run them at nothing like the pressures you mention. Far from it and contrariwise is every respect.

You may be able to use these figures to arrive at a rule of thumb for your own tyres.

My bicycle is black and red.

I hope this helps, but fear it may not.

 

[Thomk]

I was under the impression that the quoted maximums on tyres were quite a bit lower than their true maximums.

 

[Peteaud]

I bang my head against a wall several times a day and I've never had a problem. Doesn't make it the right thing to do...

why is 80 wrong?

I am comfy, the bike handles well and i dont get that many p**********s

 

[Boris Bajic]

I was under the impression that the quoted maximums on tyres were quite a bit lower than their true maximums.

I stick to them these days. Many years ago I tried running Conti SportContact slicks on my MTB at 100psi (recommended max was 80).

They gave good grip, a nice ride and were very fast, but they punctured like a bastard every time I went near a piece of gravel. I went back down to 80 and all was well with the world.

It has been ever since.

 

[black'n'yellow]

why is 80 wrong?

I am comfy, the bike handles well and i dont get that many p**********s

80 may not be wrong for you, because you haven't mentioned the kind of riding you do, the tyres you are on or how much you weigh...

 

[black'n'yellow]

I was under the impression that the quoted maximums on tyres were quite a bit lower than their true maximums.

the quoted maximum on the side of the tyre is NOT a 'recommended' pressure. It is the maximum pressure that the tyre will safely tolerate (albeit well within a safety margin, most likely).