Tyre pressure 28mm?

[bondirob]

I'm moving up from 25mm to 28mm wide tyres. Currently I run at 100psi front and just under 120psi rear. I weigh about 100kg.
After many pinch flats and faffing about these pressures do the trick.
Would anyone know how much I dare drop the pressure with 28's?

 

[Bonefish Blues]

Try here with Schwalbe's Table as a starter:

http://www.cyclingweekly.co.uk/news/product-news/whats-the-correct-road-bike-tyre-pressure-270668

 

[steve50]

The maximum pressure allowed will be printed on the wall of the tyre, you can then experiment to find the pressure / comfort zone that suits you.

 

[T.M.H.N.E.T]

Best way is experiment. I run 25mm at 115psi no problems but I drop to 100 when on my 28mm tyre equipped machine

 

[mjr]

65 front, 85 rear. 28mm, bike and rider maybe 80kg. I like my teeth to stay in. Not had a pinch flat since maybe 2002 and I suspect I'd had a slow puncture before hitting a pothole. BQTireDrop.pdf is a good file to search for.

 

[Supersuperleeds]

I pump mine up to 100psi

 

[Brandane]

I pump the rear to the max pressure as marked on the sidewall. Front maybe 10% less to give a degree of comfort over our third worlde roads.

 

[User33236]

Rear tyre:Tyre Width=28: Pressure (in PSI)= (0.33 * Rider Weight in lbs) + 33.33

Front tyre = 0.9 x rear tyre pressure.

 

[Kajjal]

It depends on the tyres, not all 28mm tyres are the same size. Just look on the side wall and see what the pressure range is. At 100KG like me you would want to be near the top end to begin with. Then just experiment to see what suits you and the riding you do.

 

[Fab Foodie]

I'm about 90 kg and run 80 front, 90 rear on Oxfordshire atrocious roads.

 

[raleighnut]

About 90 front 100 rear on the Ridgeback (Marathons) and a bit less on the Raleighs (most of which have 28s on just not as good at coping with high pressure as the Schwalbes)

 

[bondirob]

Thanks for the advice everyone.
I've done the equation kindly posted by User33236 and come up with 105 rear and 95 front so I'll give that a go.

 

[phantasmagoriana]

My 28s (Vredestein) have a max rating of 80 psi on them, so I go for that. It does make me a bit nervous running them that low, as I'm used to 25c tyres at 120 on my other bikes!

 

[S-Express]

as I'm used to 25c tyres at 120 on my other bikes!

You must weigh a lot?