Does under inflated tyres make a difference...

Page may contain affiliate links. Please see terms for details.

ray316

Über Member
As l have put in the topic thread under inflated tyres, what effect will this have on road cycling..
The reason l ask is l have been out today and did 16 miles and found it hard going and my speed seemed to be slower, got back home and felt the tyres and they was quite soft on front and back..
l left them for a few hours just incase l was unlucky enough to have slow punctures but they did'nt go flat so l put more air in both tubes...
What should a road bikes air pressure be.. MIN ans MAX...
Will it effect my speed with under inflated tyres..
 

Cycleops

Legendary Member
Location
Accra, Ghana
It will make a big difference, under inflated tyres will suck you onto the road and slow you down by offering increased rolling resistance. Always inflate to the max indicated.
 

PocketFrog

Northern Monkey
What should a road bikes air pressure be.. MIN ans MAX...

It should give you the min and max pressures on the sidewall of your tyres - it will be slightly different for each type of tyre

Will it effect my speed with under inflated tyres..

Certainly, the amount of surface area touching the road is increased and therefore rolling resistance is also increased.
 

jim55

Guru
Location
glasgow
depends on the size of the tyres as a rule the bigger the tyre (mtb type)the less pressure ,usually in the region of 60 -85 psi,as opposed to road bike tyres(wee skinny ones,23 or 25 ish size )usually they are in the region of around 100-130 psi
and yes ,under inflated tyres will affect ur ability to roll ,so in short ,max pressure if you can
 

JoeyB

Go on, tilt your head!
I massively notice a drop in tyre pressure on my road bike so would say under inflating makes a negative difference.

I need every small win i can get to turn those pedals!
 

byegad

Legendary Member
Location
NE England
I used to run my tyres at or close to maximum pressure, then lost a lot of weight, so now run at around 90% of maximum pressure, which is not only smoother but actually faster on a rough road.
 

PhunkyPhil

Regular
Location
Colchester
If the surface of the road is wet or loose lowering your pressue will improve grip but at the result of speed because of the extra roling resistance.
 

Davidc

Guru
Location
Somerset UK
Always stick with pressures in the range stamped on the tyre wall. Buy a gauge (cheapish one). To be on the safe side stay 5 psi below max or 5 psi above min.

Then as above. Higher pressure usually gives easier running, lower is more comfortable. Experiment to find the best compromise and recheck pressures at least once a week.
 

byegad

Legendary Member
Location
NE England
If the surface of the road is wet or loose lowering your pressue will improve grip but at the result of speed because of the extra roling resistance.

IF the tyre is so hard you get chatter on a rough road you are wasting power, in effect the power to move the bike up and down is coming from you. Taking just a little pressure out will allow the tyre to absorb the chatter and so you go faster. Go too low and you merely add rolling resistance so it's a fine line.
 

Gravity Aided

Legendary Member
Location
Land of Lincoln
Plus, you run the danger of "Pinch Flat", when the tube gets trapped between the rim and the road in an unproductive way. Manufacturers specifications always work best, it seems.
 
Top Bottom