Max Psi?

[simongrant]

Hi Group,
Up to now i have always inflated my tyres to manufacturers max rating without any problems at all.My new tyres came today,vittoria rubinos in red 700X23's. Now this freaked me out just a tad.They are rated at MIN 100psi MAX 150psi. Of course i have put them at 150 psi but im just a little uneasy about such a high pressure,not ridden em yet but they look great on the rim,no bulging or anything,sitting very pretty.The highest pressure ive had previous on the road bike is 120psi.I just want a little peace of mind that 150 is fine lol.

Thanks

Simon

 

[ianrauk]

If it says 150psi, then 150psi will be fine.... your arse might not like it though

 

[Flying Dodo]

If nothing else, you'll have bulging biceps getting your pump up to 150 psi.

 

[HJ]

When it says MAX 150psi it does mean maximum, you don't have to pump them that hard, 120-130psi should plenty, the ride will be harsh enough even that those pressures....

 

[Gerry Attrick]

I am 11 1/2 stone and run my Rubinos at 100 psi without any problems. No, the Lincolnshire lanes are most definitely not smooth!

 

[alecstilleyedye]

due to limitations with close fitting mudguards, i have to run my front rubino at 80psi. still ok, but it's one of the reasons the 'guards are coming off this weekend…

 

[Randochap]

To avoid pinch flats, you should consider your weight.

After that, it's all about comfort/speed. You'll actually go slower on uneven surfaces w/ higher pressure/narrower tyres.

I weigh 130-135 lbs. I never feel the need to pump 700X23s any higher than 110psi on the back and 90psi in front. On very bumpy surfaces -- such as chip seal -- lowering them by 10lbs improves the ride.

On long events, I use 28s @ 90psi

 

[HLaB]

The tyres will cope with 150psi fine but the latest C+ mag say's there is no noticeable benefit to having tyres pumped up to the max; there might even be a dis-benefit. IMLE that right the tyres can be hard but they don't need to be uncomortably solid which can slow you down. I run 120psi rated tyres in the 90-110 range just occaisionally pumping up to the 120max.

 

[karimali831]

My max is 110 PSI and when it reaches 100, I've got to use my body weight to exceed 100 psi. When I go any further than 100, it really feels like it's going to burst!

This happened on my old MTB using the cheap inner tube for like £1.24 provided by Tesco. When reaching the maximum pressure, it burst!

 

[simongrant]

Thanks for all the info,i think i will back them off to 120 or 130 and see how i go,just out of interest what do you rubino riders think of the tyre? I got them mainly for the puncture resistance and the price was very good too.I have replaced my Kenda Kampains for the rubinos.

Thanks again
Simon

 

[Randochap]

The Rubino is a good tyre. No need to run them over 110.

 

[simongrant]

Thanks Randochap,i have justput them to 110psi,i will report how they are next week as im taking the bike to the lakes for a few days.Btw the bike is a claud butler san remo 2008 and my first road bike,i know CB's are generally mocked but i have had them for a number of years and they have been great for me and my LBS is a dealer so any probs i might have and its straight in but touchwood none in years apart from usual wear and tear.May get a better road bike in the years to come but for now this is more than capable for my experience and ability Lol.

Simon

 

[fossyant]

I run my tyres at 110-120. Only did I ever go to 130 plus with tubulars for TT's

 

[RedBike]

Your tyres might be capable of 150psi but are your rims?

 

[jimboalee]

You and your bike weigh an amount ( in pounds ). There are two tyres. A greater proportion of the weight is on the rear tyre - 2/3 ish.

If you and your bike weigh 180 lb, 120 of them will be on the rear tyre, so if you pump the rear to 120 lb / sq in, there will be 1 square inch of rubber contacting the tarmac.

The less rubber that hits the road results in a lower Coefficient of rolling resistance. This is the linear element of the velocity - power curve.
If you can lessen the Crr, the amount of power required to acheive a velocity is reduced.

Hence 150 psi.

It is only a small amount compared with Aerodynamic drag, but over a 300 km, 17 hr ride, is adds up to a considerable saving.

Riding on low pressure tyres, as we all know, is a REAL drag