Narrow Tyres

[SRV]

I've been reading some old posts on this subject and feel inclined to stick my oar in.

I come from the world of wide-tyred bicycles (32mm and above). However, I recently assembled a bike with 700cx23mm tyres (they were on the wheels I bought from ebay).

Having ridden about 500 miles on it I have found that the optimum tyre pressures (resistance/comfort) for my 13 stone bulk are, front low 70's - rear low 80's. Alarming, isn't it? I am being deliberately vague as my method is to put my weight on the saddle and note the bulge on the rear and then do the same on the handlebars for the front (ignoring J Brandt's sage advice - I'm a lateish and heavyish braker - a hangover from my motorbike days). Then I use the gauge.

I've done a bit of mild (and slow) off-roading with this set-up and haven't - YET - suffered a puncture in my secondhand tyres (Kenda Koncepts - suitable both for bicycle and wheelchair use apparently. No doubt this combination and the above information will be grist to some wag's mill).

What am I doing wrong?

[rogerzilla]

I've had pinch punctures at over 150psi. You just need to find the right pothole

[Mick F]

23mm for me on Mercian.
80psi front and 120psi rear.

Lovely ride with a 531c frame and fork combo.

Used 20mm in the past, but had a couple of pinch punctures, so went to 23mm and not suffered a PP for donkey's years since.

[Jamesh]

Going soft in my old age

25mm 80psi on summer bike,

28mm on winter bike 60psi.

Cheers James

[scottg]

I've had pinch punctures at over 150psi. You just need to find the right pothole

I've gotten dented rims, but didn't flat on badly maintained rail way crossings.

Sort of like the radio that blows up, to save the fuse.

19mm tyres were the thing for a while, ever wonder why pumps went to 220psi?

[kylecycler]

Could it be that the OP's Kenda tyres' sidewalls are stiffer and heavier than those of more supple tyres and therefore compress less, so they can be ridden at relatively lower pressures without pinch flats?

I've only ever had one pinch flat - a front tube, only a couple miles into the ride after pumping the tyres (23mm Schwalbe Durano Etape) to 85 psi front, 100 psi rear at the start (maybe too low, but the ride is awful otherwise).

It happened when braking fairly hard on a badly potholed surface, but I figure it was maybe a cheapo Halfords tube that was the culprit. I usually use Schwalbe tubes.

[rogerzilla]

I've had pinch punctures at over 150psi. You just need to find the right pothole

I've gotten dented rims, but didn't flat on badly maintained rail way crossings.

Sort of like the radio that blows up, to save the fuse.

19mm tyres were the thing for a while, ever wonder why pumps went to 220psi?

I had 18mm Conti Grand Prix in the 90s. They rode about the same as 23mm.

The pumps going to 220psi is for track tubs, which you do "as hard as possible".

[TheBomber]

I've gotten dented rims, but didn't flat on badly maintained rail way crossings.

This touches on something I don't understand about 'going tubeless' - you won't pinch puncture a tube at lower pressures when riding tubeless, but are you not still at risk of damaging the rims? If we take Scott's experience above as an exception that proves the rule, aren't pinch punctures an early warning system that you are riding at too low a pressure?

This is a genuine question from someone who has never tried riding tubeless, rather than a criticism of it.

[gregoryoftours]

I've wondered about it a little bit, I don't know the answer but it's an acknowledged problem with tubeless as you can by foam tubeless inserts that are supposed to protect the rims a bit, plus help to keep the bead seated at lower pressures.

[simonhill]

Just to throw in another variable, I wonder how accurate everyone's pressure gauges are.

[Norman H]

The OP's pressures seem alarmingly low to me. I've only got one bike on 23mm tyres at the moment and I'm running 4.5 bar front 5.5 bar rear. I only weigh 56kg though, and the bike weighs 9kg. If the frame has clearance, and at 13 stone, I'd be looking to increase tyre size to 25 or 28 mm.

Have a play with this tyre pressure calculator.

https://roubert.name/joakim/pressure/