# Gravel bikes



## TAV (13 Oct 2022)

Hi are there guys or girls doing audaxs on gravel bikes with 1x groupsets with large tyres or will they be a bit slow with the larger tyres on?


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## Cycleops (13 Oct 2022)

No experience of doing Audaxes but a bike with fatter tyres, say 35c - 45c are always going to be a bit slower than something on 28c. Always going to be.


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## TAV (13 Oct 2022)

Yeah I know I've got 47mm on mine great for the cycle trails but I think I'll have to go down to maybe 35mm for the long audaxs


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## Ajax Bay (13 Oct 2022)

The key thing for these wider tyres is their construction: are they made for the average hybrid or have they got racing pedigree eg GP5000, which you can get in 32mm. At the right pressures these will give you relatively low rolling resistance.
https://www.bicyclerollingresistance.com/specials/grand-prix-5000-comparison
And have a good poke round that site.
Bear in mind the various qualities people look for in a tyre for long rides eg randonnees varies (do you value robustness or low rolling resistance more?)
I have shod with 4000s (and have a few in stock) but also Michelin Pro4 Endurance.
Wider: Rene Herse and these 44s: rene-herse-snoqualmie-pass


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## cougie uk (13 Oct 2022)

TAV said:


> Hi are there guys or girls doing audaxs on gravel bikes with 1x groupsets with large tyres or will they be a bit slow with the larger tyres on?



The wheels I have on will take my 25mm GP5000s as well as my 38mm knobblies.

If I'm doing a long road ride - I'd just fit road tyres unless you want a really good workout.

I don't know what your roads are like but 35mm is on the wider side of things.


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## matticus (14 Oct 2022)

cougie uk said:


> I don't know what your roads are like but 35mm is on the wider side of things.



Yeah. Although:
- I've done rides [with 25s] on surfaces that beat me up so much [mainly 600k+], I would have been just as fast overall on 35c.
France? Welsh A-roads? go Narrow.
South of England, or Ireland, or anywhere you know there will be some pavé? Go a bit fatter

- Rims that take 44mm *might* not be compatible with 28-30mm.


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## TAV (14 Oct 2022)

I've emailed the wheel manufacturers and they said I could fit 32c on them.


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## Ajax Bay (14 Oct 2022)

What are the rims, do you know? The internal rim width is the critical measurement eg 17mm. Sheldon says you can go up to twice that dimension in tyre width, quite safely, without any effect on handling (in corners).
As I said, choose from a combination of tread depth, sidewall thickness, rolling resistance, weight, cost. I had 4000s on for LEL and PBP. But others think Continentals are the work of the devil.


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## iandg (14 Oct 2022)

I've done audax on a Long Haul Trucker with 35c tyres. If you can maintain the required speed and finish within the time limit it doesn't matter what you ride.


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## TAV (17 Oct 2022)

I've got 650b wheels and I can't find any narrower than 40mm which I think is to big and tubless I've got on at the moment I'm not sure.


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## Cycleops (17 Oct 2022)

That is a problem with a size that is primarily aimed at mountain bikes.


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## TAV (17 Oct 2022)

Yeah I've guessed that I've put it up for sale on this site hopefully I can shift it on as gravel biking isn't for me. I'm going to build my audax bike back up with the money and get back on the road


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## matticus (18 Oct 2022)

Malmesbury?


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## Ajax Bay (18 Oct 2022)

matticus said:


> Malmesbury?


Looks very like it.


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## TAV (18 Oct 2022)

Yeah it was my first audax from Cardiff to Malmesbury and back me and two other guys were the last in. What a ride I was in a world of pain coming in it was raining and dark.

That was my first and last I thought but I want to give it another go it was in March this year not really a good idea for my first.


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## TAV (18 Oct 2022)

When I build the bike back I'm thinking of going for a triple or maybe a 42 32 chainset any suggestions?


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## Ajax Bay (18 Oct 2022)

Large ring of 42t means you'd spin out at relatively low downhill speeds, even with a 11-32 cassette.
https://www.gear-calculator.com/?GR...25,28,32&UF=2215&TF=90&SL=2.6&UN=KMH&DV=teeth
Suggests spin out at about 30mph (assumes max cadence is 100rpm - your souplesse may vary).
Have a play with the calculator (eg to look at a triple, but NB rear derailleur capacity will mean (arguably) a 28t max sprocket).


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## TAV (19 Oct 2022)

OK cheers for the advice 👍


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## Sallar55 (21 Oct 2022)

What does 42 and a 9 sprocket give ? Campag have cassettes that end in 9 and 10 tooth sprockets, no need for a big ring. I wonder when triples with close ratio cassettes will be the next must have. Waiting for Stronghlight to make carbon triples (pulsion) again.


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## Ajax Bay (21 Oct 2022)

Sallar55 said:


> Campag have cassettes that end in 9 and 10 tooth sprockets


Linky?


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## Sallar55 (21 Oct 2022)

This https://www.campagnolo.com/WW/en/Mechanical_Groupsets/ekar/gravel2


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## Ajax Bay (22 Oct 2022)

So @Sallar55 you are floating the idea of the OP fitting a 13-speed Campagnolo Ekar drivechain (to get the 9sp sprocket).
Bike is a Genesis-equilibrium
Apart from cost (cassette alone is £200), the OLD of the drop outs needed is 142.5mm (the OP's bike has 130mm).
Triples with close ratio cassettes either can't give a short enough low gear, or can't offer a long enough high gear (or both) so I very much doubt it will be the "next must have".


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## Sallar55 (23 Oct 2022)

All depends upon your riding style. Do you struggle up the hills and try to make time back on the descents, that way you are always working. The other strategy is to attack the hill and drink,eat ,recover while conserving energy on the descent. You pick the gearing for what suits you. I like triples as it's easy to set the gearing you like. Single chainring with 13 is nice as well, will Shimano go better next.


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## Scottish Scrutineer (2 Nov 2022)

TAV said:


> When I build the bike back I'm thinking of going for a triple or maybe a 42 32 chainset any suggestions?


I run sub-compact chainrings (48/32) on two of my road bikes with 11-32 or 11-34 cassettes. Occasionally run out out leg speed when in 48:11, but by then I'm usually considering freewheeling.
My other bike is a Kinesis At, which has 1x gearing 40T chainring and 11-42 cassette. I'd be happy to use it on a century ride, but might consider fitting the 35mm Voyager Hypers rather then the 38mm GavelKing SK tyres.


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## TAV (2 Nov 2022)

Scottish Scrutineer said:


> I run sub-compact chainrings (48/32) on two of my road bikes with 11-32 or 11-34 cassettes. Occasionally run out out leg speed when in 48:11, but by then I'm usually considering freewheeling.
> My other bike is a Kinesis At, which has 1x gearing 40T chainring and 11-42 cassette. I'd be happy to use it on a century ride, but might consider fitting the 35mm Voyager Hypers rather then the 38mm GavelKing SK tyres.



I've got a gravel bike/ touring bike but I fancy going back to audaxs but I think it wouldn't be rite with the large 47mm tyres and if I put say 32mm on there I think it would look odd with a massive gaping the folks.


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## matticus (2 Nov 2022)

TAV said:


> I've got a gravel bike/ touring bike but I fancy going back to audaxs but I think it wouldn't be rite with the large 47mm tyres and if I put say 32mm on there I think it would look odd with a massive gaping the folks.



That would NOT do - we are VERY style-conscious at AUK. Not like those awful sportives, gravel rides, yada yada ...


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## ColinJ (3 Nov 2022)

TAV said:


> I think it would look odd with a massive gaping the folks.


Like this, you mean? 








matticus said:


> That would NOT do - we are VERY style-conscious at AUK.


I suppose I would lose even _more _style points for walking my bike up that steep hill!


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## Ming the Merciless (3 Nov 2022)

TAV said:


> I've got 650b wheels and I can't find any narrower than 40mm which I think is to big and tubless I've got on at the moment I'm not sure.



Depends on the tyres but there are some tyres that width in 650b just as quick a narrower tyres on 700c. A friend does audax on that kind of width 650b.


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## Ming the Merciless (3 Nov 2022)

ColinJ said:


> Like this, you mean?
> 
> View attachment 666812
> 
> ...



I see you are trying to balance on one leg whilst wearing XXXXL shorts..


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## Jameshow (3 Nov 2022)

TAV said:


> I've got a gravel bike/ touring bike but I fancy going back to audaxs but I think it wouldn't be rite with the large 47mm tyres and if I put say 32mm on there I think it would look odd with a massive gaping the folks.



More to the point the funny handlebars would cause a few comments!!


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## ColinJ (3 Nov 2022)

Ming the Merciless said:


> I see you are trying to balance on one leg whilst wearing XXXXL shorts..


Ha ha!

There was another leg hidden somewhere... 







The shorts are actually only XL - I'm losing weight so my legs are getting smaller!


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## ColinJ (3 Nov 2022)

Ah - the balance on one leg test - I get it!


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## Ajax Bay (3 Nov 2022)

https://www.cyclesolutions.co.uk/11045/products/continental-contact-speed-275650b-tyre.aspx


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## matticus (4 Nov 2022)

Ming the Merciless said:


> I see you are trying to balance on one leg whilst wearing XXXXL shorts..



You see - it's started! Let no-one say they weren't warned about the AUK Style Police ...


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