Author Topic: rolling resistance  (Read 4664 times)

rolling resistance
« on: 11 April, 2019, 12:27:05 pm »
Interesting review of new GP5000s at bicycle rolling resistance.

https://www.bicyclerollingresistance.com/specials/grand-prix-5000-comparison#sizeweight

Introduces a new category of measurement (for that site) -- rolling resistance at a similar level of comfort -- and strikes me as a well-thought through review of many of the issues.

(this could go in reviews, but it was the general thoughts of the review that seemed more interesting.)


Alex B

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Re: rolling resistance
« Reply #1 on: 11 April, 2019, 05:35:53 pm »
I'm running some tubeless ones and I've been impressed with them so far. They go on easily, are quite conservatively sized (the 25mm ones come up 26mm wide on a 25mm rim), and seem tough - no mishaps so far in approx. 1000 km including some very rough riding in the Peak District.

Subjectively, the bicyclerollingresistance tests ring true: they feel fast and comfortable. They have the makings on a classic long-distance tyre I think!

Phil W

Re: rolling resistance
« Reply #2 on: 11 April, 2019, 05:52:20 pm »
Rolling resistance 10 watts per tyre (at 18 mph) for the 32mm at 60 psi is really rather good. Seems those latex tubes make a difference as well. I run my 32mm (not these tyres) at 65 psi rear and 55 psi front. 

CrazyEnglishTriathlete

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Re: rolling resistance
« Reply #3 on: 14 April, 2019, 07:15:07 pm »
Out of interest, what is the difference in rolling resistance between nice smooth tarmac (like on Swiss roads where you hardly feel a vibration at 110psi) and the typical British lets see what's the coarsest grade of aggregate we can get away with where the stones will stick together surface where prolonged riding makes you contemplate vibration white finger compensation (at any tyre pressure)?
Eddington Numbers 130 (imperial), 182 (metric) 571 (furlongs)  114 (nautical miles)

LittleWheelsandBig

  • Whimsy Rider
Re: rolling resistance
« Reply #4 on: 14 April, 2019, 07:34:42 pm »
Lots but low tyre pressures in wide, supple tyres help close the gap.
Wheel meet again, don't know where, don't know when...

Re: rolling resistance
« Reply #5 on: 17 April, 2019, 08:24:08 am »
They go on easily

Not on my rims! I broke a tyre lever (first time ever) fitting one yesterday.  Finally got it on with metal levers after leaving it against a radiator for a couple of hours to warm up.  I don't fancy ever having to re-fit it out on the road.

T42

  • Apprentice geezer
Re: rolling resistance
« Reply #6 on: 17 April, 2019, 10:48:52 am »
Your man in Paris-Roubaix didn't seem too impressed.

Kristoff it was : http://www.cyclingnews.com/news/kristoff-regrets-big-risk-after-using-tubeless-tyres-in-paris-roubaix/
I've dusted off all those old bottles and set them up straight

Re: rolling resistance
« Reply #7 on: 17 April, 2019, 10:55:38 am »
Your man in Paris-Roubaix didn't seem too impressed.

Kristoff it was : http://www.cyclingnews.com/news/kristoff-regrets-big-risk-after-using-tubeless-tyres-in-paris-roubaix/

He ran 25mm over the cobbles then complained about issues of flats when hitting potholes?
He wasn't using contis either.
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T42

  • Apprentice geezer
Re: rolling resistance
« Reply #8 on: 17 April, 2019, 01:29:58 pm »
He did use tubeless for his recon, but, as he says, in the pack you don't get the choice of where to put your wheels.
I've dusted off all those old bottles and set them up straight

zigzag

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Re: rolling resistance
« Reply #9 on: 17 April, 2019, 02:08:26 pm »
to use a delicate pair of 25mm tyres on rough cobbles by a rider of his build? this doesn't make a lot of sense to me..

Re: rolling resistance
« Reply #10 on: 17 April, 2019, 02:45:11 pm »
Clearly using 25mm tyres was the problem.  Tubeless / tubes = largely irrelevant.

Re: rolling resistance
« Reply #11 on: 17 April, 2019, 02:50:59 pm »
As ZZ said, the Graphene's are a delicate tyre. I suspect the tubs (whic I assume) he switched to were also 25mm, but less fragile.
We are making a New World (Paul Nash, 1918)

LittleWheelsandBig

  • Whimsy Rider
Re: rolling resistance
« Reply #12 on: 17 April, 2019, 03:36:07 pm »
Most tubs used at PR are 28-33mm wide, not 25mm.
Wheel meet again, don't know where, don't know when...

Pedal Castro

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Re: rolling resistance
« Reply #13 on: 18 April, 2019, 07:58:05 am »
Out of interest, what is the difference in rolling resistance between nice smooth tarmac (like on Swiss roads where you hardly feel a vibration at 110psi) and the typical British lets see what's the coarsest grade of aggregate we can get away with where the stones will stick together surface where prolonged riding makes you contemplate vibration white finger compensation (at any tyre pressure)?

I have a graph showing this somewhere, I can't remember where I got it from but I'll dig it out and post it later.

Re: rolling resistance
« Reply #14 on: 20 April, 2019, 11:59:59 am »
Cheers for sharing - very interesting and educational