Changing tyres!

For discussions about bikes and equipment.
Brucey
Posts: 42940
Joined: 4 Jan 2012, 6:25pm

Re: Changing tyres!

Postby Brucey » 16 Jul 2020, 7:11pm

I think it is fair to say that roller tests give you a pretty good idea of how tyres of similar width/build are likely to compare with one another, when all else is equal. It is much less clear that they allow a good comparison of likely Crr values on real roads, when fitted to real bikes, between tyres of greatly different widths. Such comparisons may also vary with the quality of the road surface and the characteristics of the bike the tyres are on, too.

Until there is a test that allows for these things, 'hearsay' might be as good as it is going to get if you want to make such comparisons.

cheers
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reohn2
Posts: 40711
Joined: 26 Jun 2009, 8:21pm

Re: Changing tyres!

Postby reohn2 » 16 Jul 2020, 7:22pm

freeflow wrote:The rolling resistance data shows a 15W difference between GP5000 622 28C and Vittoria Hypers 622 37C. What that 15 watt difference means in terms of speed difference is rider dependent.

The GP5000 may very well be the fastest on paper and the difference would show on shorter rides.
But that's not the whole story,on longer rides comfort is an ever increasing factor,and when fatigue sets in the longer you're in the saddle,especially on UK crapmac roads when that fatigue robs the rider of power to the pedals.
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freeflow
Posts: 1434
Joined: 29 Aug 2011, 1:54pm

Re: Changing tyres!

Postby freeflow » 16 Jul 2020, 8:23pm

Colin531, you converted me to Vittoria Hypers many years ago. The bike that used them was stolen, so I'm stuck with 28c tyres at the moment. The GP5000 have put a grin on my face. For me, that 15W makes areal difference in how the bike feels. I've no idea what it means for other riders.

Brucey
Posts: 42940
Joined: 4 Jan 2012, 6:25pm

Re: Changing tyres!

Postby Brucey » 16 Jul 2020, 8:32pm

freeflow wrote: ….For me, that 15W makes areal difference....


it might do, if it actually exists on real roads rather than rollers.....?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

hamster
Posts: 3786
Joined: 2 Feb 2007, 12:42pm

Re: Changing tyres!

Postby hamster » 17 Jul 2020, 9:34am

freeflow wrote:Colin531, you converted me to Vittoria Hypers many years ago. The bike that used them was stolen, so I'm stuck with 28c tyres at the moment. The GP5000 have put a grin on my face. For me, that 15W makes areal difference in how the bike feels. I've no idea what it means for other riders.


On the same bike, I reckon GP4000sII were worth 1-2 minutes on an 18 mile loop. I could make it under the hour with them, typically 1:01 or 1:02 on GP4Season. The ride was also more supple. I've not gathered GP5000 times yet.

There is undoubtedly a psychological effect of whether something 'feels fast' which isn't replicated in times, and (as said) what's good for a short TT can be eliminated by fatigue.

reohn2
Posts: 40711
Joined: 26 Jun 2009, 8:21pm

Re: Changing tyres!

Postby reohn2 » 17 Jul 2020, 9:48am

In an attempt to answer the OP's question WTB Horizons get good reviews,as do Rene Herse Babyshoe Pass,neither tyre is cheap,but then quality rarely is.
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Jamesh
Posts: 1805
Joined: 2 Jan 2017, 5:56pm

Re: Changing tyres!

Postby Jamesh » 17 Jul 2020, 9:26pm

How do gp5000 compare to say Michelin pro4???

Cheers James

reohn2
Posts: 40711
Joined: 26 Jun 2009, 8:21pm

Re: Changing tyres!

Postby reohn2 » 17 Jul 2020, 10:37pm

Jamesh wrote:How do gp5000 compare to say Michelin pro4???

Cheers James

Are they available in 650b?
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seph
Posts: 163
Joined: 3 Sep 2010, 8:22pm

Re: Changing tyres!

Postby seph » 18 Jul 2020, 8:11am

[quote][/Agreed GP5000 are wonderfully fast and supple tyres. I love them.
If you ride roads with lots of trash and flints be warned that they may not last well. I typically get around 1000 miles out of one before it gets terminally cut. For me it's a summer-only tyre. Michelin Pro4 Endurance is not quite as fast, but way tougher in


....1000 miles.. is that it? Blimey.. :shock: I suppose you would get faster at swapping tyres.. :wink:

reohn2
Posts: 40711
Joined: 26 Jun 2009, 8:21pm

Re: Changing tyres!

Postby reohn2 » 18 Jul 2020, 9:51am

freeflow wrote:https://conti-tyres.co.uk/road-and-track/clinchers/grand-prix-5000

Thanks,I was unware of that.
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