rolling resistance for different tyres and pressure

aidanki

hi all,

thought this was interesting today

http://www.bicyclerollingresistance.com/road-bike-reviews/schwalbe-pro-one-tubeless-2016

rolling resistance for different tyres and pressure


as each bike has two tyres I can easy save 10W by having low friction tyres it appears. What do I output as Im going alone the road typically, Ill guess 180-200w, so I can get ~5% improvement by having proper tyres and pressures.

and its a lot cheaper than trying to upgrade to carbon

Lumen

aidanki wrote: »

as each bike has two tyres I can easy save 10W by having low friction tyres it appears

According to the tests in that article, the difference between the Schwalbe Pro One Tubeless and Conti 4000S II is 1.3W

Given the difficulty of fixing a tubeless tyre with a puncture that can't be sealed by the sealant (i.e. using an inner tube) I think I'd rather stick with regular clinchers.

I have an expensive set of tubeless disc clinchers that I'll probably sell after discovering how difficult it is to mount regular tyres on them.

Alek

difficulty of fixing a tubeless tyre with a puncture that can't be sealed by the sealant

What is difficult in putting the tube in when it goes flat?

I have an expensive set of tubeless disc clinchers that I'll probably sell after discovering how difficult it is to mount regular tyres on them

Do they have a deeper section in the middle of the rim, like in Shimano UST? If so there is a neat trick to this - I have no problem mounting any tyres on mine now. It was a nightmare before I've discovered this.

Lumen

Alek wrote: »

What is difficult in putting the tube in when it goes flat?

I can't get the tyre on without extreme effort because the tube occupies the centre channel.

Alek wrote: »

Do they have a deeper section in the middle of the rim, like in Shimano UST?

Yes, but that section is blocked by rim tape. Without rim tape the inner tube blows through the spoke holes (even though they're air tight).

Alek wrote: »

If so there is a neat trick to this - I have no problem mounting any tyres on mine now. It was a nightmare before I've discovered this.

Please share!

Alek

Yes, but that section is blocked by rim tape. Without rim tape the inner tube blows through the spoke holes (even though they're air tight).

A-ha. My wheels don't have spoke holes, there is no rim tape, so I can position bead in there while mounting the tyre. This makes it easi-peasi.

How about changing your rim tape to more flexible one? Or using some strong adhesive tape instead, that would conform to the shape of the rim bed?

Lumen

Alek wrote: »

A-ha. My wheels don't have spoke holes, there is no rim tape, so I can position bead in there while mounting the tyre. This makes it easi-peasi.

That would explain it.

Alek wrote: »

How about changing your rim tape to more flexible one? Or using some strong adhesive tape instead, that would conform to the shape of the rim bed?

I have tried two types of rim tape and a couple of types of adhesive tape (gorilla, electrical).

I can choose between any combination of "inner tube blows" and "tyre is very hard to get on", but there is no acceptable compromise.

And by "very hard" I mean "even with soapy water, three of my best levers, patience and then swearing".

Alek

"very hard" I mean "even with soapy water, three of my best levers, patience and then swearing".

Ouch.

Have you tried contacting the manufacturer to politely ask what the hell do they though designing this?

Lumen

Alek wrote: »

Ouch.

Have you tried contacting the manufacturer to politely ask what the hell do they though designing this?

They're tubeless wheels so I can hardly complain that they don't work as designed.

OP, sorry to drag your thread off-topic. Enjoy the extra 2.6W :-)

Alek

They're tubeless wheels so I can hardly complain that they don't work as designed.

Tubeless does not mean impossible to mount tyres on. Just sayin'.

aidanki

Lumen wrote: »

They're tubeless wheels so I can hardly complain that they don't work as designed.

OP, sorry to drag your thread off-topic. Enjoy the extra 2.6W :-)

look at table along RHS of page I sent, its a lot more than 2.6W between first and last....

Lumen

aidanki wrote: »

look at table along RHS of page I sent, its a lot more than 2.6W between first and last....

Where are you getting 5W per tyre from?

The only table with watts in it doesn't compare tyres, it compares pressures, but the difference between 100psi and 120psi is only 0.6W, 60psi would be unusable and 80psi marginal (might get away with it on the front with a light rider).

Carawaystick

The table on the top right has watts


Schwalbe Pro One Tubeless 11W
....
Gatorskins 19W

aidanki

Carawaystick wrote: »

The table on the top right has watts


Schwalbe Pro One Tubeless 11W
....
Gatorskins 19W

you got to it before I did

Lumen

Carawaystick wrote: »

The table on the top right has watts


Schwalbe Pro One Tubeless 11W
....
Gatorskins 19W

Oh, that table. :pac:

Full results and test details.

http://www.bicyclerollingresistance.com/road-bike-reviews
http://www.bicyclerollingresistance.com/the-test

The drum is probably too smooth for the results to map perfectly to Irish roads (lots of other articles on the benefits of wider tyres) but the tyre comparisons are interesting.

Grand Prix 4000S II with Latex Tube comes top of the list, although I'm not sure 1W per tyre is worth pumping them every day.

Alek

The drum is probably too smooth

Still better than smooth drum that (supposedly) producers use for their own testing.

Borderfox

Michelin hi-lite 19mm ftw

cdaly_

Bicycle Quarterly has a number of articles on the subject of "performance of tires". Using real road surfaces* and accounting for suspension losses, they conclude that:

• Tyre casings make a big difference in rolling resistance.
• Above a certain pressure (which varies per tyre), there is no performance benefit to be gained.
• Fairly low pressures can be just as fast as high/very pressures (but there is a risk of pinch flats)
• Moderate pressures (80-100psi) are the worst for performance.
• Low pressures are much more comfortable.
• Wider tyres roll faster than narrow

For the most comfortable (and fast) ride, run the widest version of your favourite tyre that your frame will accommodate at a fairly low pressure.

I'm running 37mm tyres at around 40-50psi for the last year and loving them...


*A smooth/smoothish roller does nothing to induce vibrations in the bike/rider which are a big source of losses.

smacl

cdaly_ wrote: »

I'm running 37mm tyres at around 40-50psi for the last year and loving them...

Wow, interesting. I was already feeling a bit decadent on my 32mm tyres at 70f/80b psi. Some experimentation required, as extra comfort at no cost is always greatly appreciated.