A while back we were discussing tire pressure vs. rolling resistance. I sent this email to Tufo and got this response from Milan Simek. I thought some of you might be interested.
Richard
-----Original Message-----
To: TUFO
Subject: Optimal tire pressures
Subject: RE - optimal tire pressures
Hi,
Some of us on the forum at slowtwitch.com are having a discussion about the
optimal inflation pressure for Tufo and other tubular tires.
One of the contributors suggested that a tire can actually run slower at a
higher than ideal pressure. Do you agree?
Can you offer any advice on this subject?
Answer:
Yes, we agree - but this pressure is very high /surelly above 29O lbs/sq in/ and in this case is the contact surface with the road so slight that the slip appears during the stroke->and this is the main reason why the rolling resistance is increasing – it is thanks to the slip effect.
In case the wheel is not in the stroke ( for example by front whell) the rolling resistance is decreasing. The lowest rolling resistance shows the steel wheel of wagon on the rail - there is no any deformation .
For instance I ride a set of 19mm Tufo S3 Lites on 650c Hed3 wheels with a
Kestrel KM40. I weigh 155 lbs. and inflate my tires to 160 lbs/sq in. I
find the ride and handling acceptable at this pressure.
Answer:
The inflation figures are mentioned onto the tubulars.
For example our racer representant Ms. Lada Kozlikova achieved silver and gold medal on the world championship in Danmark (track disciplines).
She used our special TUFO ELITE tubulars (weight only 88g!!!) which were inflate by helium up to 250 lbs/sq in!!!
Is there a way to estimate an ideal pressure for the fastest ride or is this
meerly a matter of trial and error? Does the answer depend on how rough or
smooth the pavement is?
Answer:
Obviously the inflation for the pavement-riding is upto each of you – this individually issue. But to ride e.g. 180 km with the low pressure just because there are 4 pavement - parts of 1OO m is worse then to ride the same under the high pressure…