Tyre pressure

bikerbart

Hi, Got my first ever road bike today. The tyres are Kenda 700x23c they say 110psi max on them, I'm 11-1/2 stone what sort of pressure should I be setting them at?

Daddy2Coull

11.5 stone? ou need to put both feet on the scales!!!

i'm running at 105psi at 13.75 stone

night_porter

It really depends on the type of roads you are riding because rough roads will increase the chances of pinch flats if you run with a lower pressure.

To be safest keep the tyres between 100-110psi for now but if the roads are super smooth then you could drop 10psi off of that if you find the ride too harsh (give it a month or so before you change).

Secteur

My tyres say "Max 115psi" on them, so I always keep them at 110psi.

No idea if that's right or wrong.

Even in the wet I run them at 110psi, though I know I should probably run them lower, but the roads are so rough and sh*tty I worry about a pinch flat.

Paul E

I run mine at between 95 and 100, tried higher and the ride quality went to sh1t

Barteos

Using the 15% drop method http://www.bikequarterly.com/images/TireDrop.pdf and assuming that you, bike and kit weigh 190lbs, optimal pressure would be around 115PSI rear and 75PSI front.
On rough roads, you should lower the pressure, in order to reduce rolling resistance and increase comfort and grip.
If at the optimal (lowered) pressure you suffer pinch flats, your only option is to move to wider tyres.

smurfylicious

Interesting thread. Mine have an upper and a lower limit, 125psi and 115psi respectively. Given that they're 700*23 what is the lower limit for? Is it to guard against pinch punctures and rim damage? If it is then surely the manufacturer has to arbitrarily decide on a maximum rider weight.

bikerbart

Interesting stuff, thanks

mouth

bikerbart wrote:

Hi, Got my first ever road bike today. The tyres are Kenda 700x23c they say 110psi max on them, I'm 11-1/2 stone what sort of pressure should I be setting them at?

I have the same tyres (Carrera by any chance?) and run them at 100psi, weight 16.5stone.

stephenballantyne

I'm 11 stone and run the rear at 120psi and the front slightly lower (needless to say, I don't get pinch flats). Having read this thread I'm now considering dropping the pressure....especially since the roads east of London aren't exactly smooth!

Secteur

so the rear tyre should be lower than the front (or is that the other way around)? They aren't meant to be run equally?

inseine

Using the 15% drop method http://www.bikequarterly.com/images/TireDrop.pdf and assuming that you, bike and kit weigh 190lbs, optimal pressure would be around 115PSI rear and 75PSI front.

I understand the theory but that sounds very soft for a front tyre. I think that if you were out of the saddle on a hill you'd really notice the difference, in a bad way. Interesting concept though.

gavbarron

110 front and rear, roads aren't ideal round here but I don't notice them being discernibly smoother if I reduce pressure slightly

davem399

Secteur wrote:

so the rear tyre should be lower than the front (or is that the other way around)? They aren't meant to be run equally?

I tend to run the rear tyre about 5 to 10 psi higher than the front, typically around 100 psi front, 110 psi rear. My reasoning for this is that is the rear tyre is more heavily loaded than the front. This is on tyres with a stated max of 125 psi.

worthydolt

When I last bought a new bike I commuted on it the following day (40 mile round trip). I was drafting the review in my mind: "Compliant, comfy, forget your steel frames" then I discovered the tyres had only 30 PSI in them. I didn't pick up any punctures though, thankfully.
I notice very little difference between 100 and 150 PSI so run them at the maximum stated on the sidewall. I'm all about the rolling resistance.

elmsallmissile

http://www.bikequarterly.com/images/TireDrop.pdf

Alibran

Both at 110psi (they're rated 100-130).

I have about a mile of really nasty, badly patched roads here before I get onto mostly smooth tarmac, so I figure a mile of taking it steady and still getting shaken to bits at each end of the ride is worth it to avoid pinch punctures, and once I get out on the proper roads, it's lovely and smooth.

Hoopdriver

FYI: Rolling resistance actually increases if you go much above 110psi

I weight about 12 stone and although my Conti 4 season GPs are rated to 110psi, I keep mine at about 95psi - no pinch flats and very comfortable - but not gushy - ride

bikerbart

inseine wrote:

Using the 15% drop method http://www.bikequarterly.com/images/TireDrop.pdf and assuming that you, bike and kit weigh 190lbs, optimal pressure would be around 115PSI rear and 75PSI front.

I understand the theory but that sounds very soft for a front tyre. I think that if you were out of the saddle on a hill you'd really notice the difference, in a bad way. Interesting concept though.

Does sound a bit low at the front. Going off the 60/40 ratio if I had 100 in back I think that makes in 66 in front. Think I'll start off with 100/90 & see how that feels and tweak it from there. I'm happy to sacrifice some comfort/performance to avoid punctures

& yes Mouth, 'tis a Carrera, well spotted