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Gravel Bike Gearing


T_Boss

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So I am a mountain biker at heart, but the idea of gravel bikes for commenting and country roads riding is starting to make more and more sense. I would never replace a mountain bike with a gravel bike, but I think it’s a nice in between option as an extra bike.

 

If we manage to recover from the financial disaster that has been caused by the outbreak, I would consider adding one to the stable.

 

I have a question about gearing. Most gravel bikes seem to come out running MTB type group sets, (SLX or XT), and gearing the same as a mountain bike. Why is this? The biggest issue I have with using the mountain bike for reasonable easy backroads riding and tar, is that the gearing offered by modern mountain bike groupsets, even with a 34t chainring and 10t cassette, is inadequate and sees you spinning out on flat fast sections.

 

The kind of riding I would do on a gravel bike would also never need the low end gearing offered by a 50t rear.

 

So my question is, is roadbike gearing not more suited to gravel bikes?

 

My other option instead of buying a “gravel” bike would be to build up my dads old Marin Ti mtb frame, as a gravel bike, and then I would have more suitable gearing anyway, but I will be limited on fork options.......

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Well, I think MTB's are limited by the front chainring size on a 1x setup, hence the more MTB-like gearing.

 

Edit: And well, it's probably cheaper than road groupsets.

 

On my bike I have an 11-36 at the back, with I think a 36-42 gravel crankset up front, which is just lovely range of gears, especially on the fast and flat sections. However as Ashchest had mentioned, a 1x11 with a 42 up front and 42 at the back should work just fine as well. The 1:1 ratio has gotten me up some pretty steep inclines on the gravel bike before.

Edited by bertusras
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I'm running 50-34 road crank and 11-36 (10 sp) mtb cassette.

 

Have changed over to 46-34 and 11-40 to swap some top end for bottom end (touring as well as gravel bike) but haven't tried it out yet due to lockdown.

 

Well, I think MTB's are limited by the front chainring size on a 1x setup, hence the more MTB-like gearing.

 

Edit: And well, it's probably cheaper than road groupsets.

 

On my bike I have an 11-36 at the back, with I think a 36-42 gravel crankset up front, which is just lovely range of gears, especially on the fast and flat sections. However as Ashchest had mentioned, a 1x11 with a 42 up front and 42 at the back should work just fine as well. The 1:1 ratio has gotten me up some pretty steep inclines on the gravel bike before.

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Do they have MTB gearing?

 

I don't think too many Gravel bikes are sold with anything smaller than a 40 tooth up front?

 

I ran 42 up front and 11-42 cassette which worked perfectly for Swartberg GF and almost all other applications.

 

I have subsequently canned 1x and run 50/34 up front with an 11-36 cassette. This covers all necessary gear ranges. 

 

MTB gears these days are commonly specced 32 up front 11-50 so there is quite a difference.... 

 

Gravel bikes are cool... Just make sure you get good brakes

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I was an early adopter and bought a Niner RLT back in 2015.  Those days it was specced to typical Cx gears being 46/36 and 11-32 at the back.  I struggle badly on the steep hills, especially with the bike being heavy as well.

 

I fully agree that a 50/34 with a 11-36 can basically take you anywhere from a gravel perspective, and you will not spin out on the flats/tar.

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Do they have MTB gearing?

 

I don't think too many Gravel bikes are sold with anything smaller than a 40 tooth up front?

 

I ran 42 up front and 11-42 cassette which worked perfectly for Swartberg GF and almost all other applications.

 

I have subsequently canned 1x and run 50/34 up front with an 11-36 cassette. This covers all necessary gear ranges.

 

MTB gears these days are commonly specced 32 up front 11-50 so there is quite a difference....

 

Gravel bikes are cool... Just make sure you get good brakes

Thanks, to be fair I haven’t actually looked closely enough at the hearing, but the couple of bikes i have looked at online, all had SLX cranksets. I haven’t seen an SLX 2x crank with bigger than 34t before, but maybe I’m wrong.

 

I like the idea of a 50/32 or something similar up front. Will just have to make sure whatever frame I choose in the end will clear a 50t chainring without hassles at the chain stays.

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+1 on good brakes. My cantis are lovely but can make life a little exciting diving down a gravel hill...

 

 

Do they have MTB gearing?

 

I don't think too many Gravel bikes are sold with anything smaller than a 40 tooth up front?

 

I ran 42 up front and 11-42 cassette which worked perfectly for Swartberg GF and almost all other applications.

 

I have subsequently canned 1x and run 50/34 up front with an 11-36 cassette. This covers all necessary gear ranges.

 

MTB gears these days are commonly specced 32 up front 11-50 so there is quite a difference....

 

Gravel bikes are cool... Just make sure you get good brakes

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+1 on good brakes. My cantis are lovely but can make life a little exciting diving down a gravel hill...

Eggzackkerly.

 

I love my old Ritchey Swiss+Cross which I now use as my gravel bike but even though the Paul Component Cantis were the dogs bollocks in the day, they are not in the same league as the most useless hydraulic disks.

 

Also have 50/34 crank but with an old road RD, only 12-30 at the back. If it gets too steep I just have to put it into low-range and walk. Hasn't happened yet but will use something else if I want to bike-pack and carry extra bags in the Swartberg again.

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Thanks, to be fair I haven’t actually looked closely enough at the hearing, but the couple of bikes i have looked at online, all had SLX cranksets. I haven’t seen an SLX 2x crank with bigger than 34t before, but maybe I’m wrong.

 

I like the idea of a 50/32 or something similar up front. Will just have to make sure whatever frame I choose in the end will clear a 50t chainring without hassles at the chain stays.

As a matter of interest, which bikes are specced with XT/SLX cranks?

 

Most stock gravel bikes are specced with SRAM and the few I have seen with Shimano have 105, Ultegra road or GRX.

 

I would be really interested to know which factory bikes have Shimano MTB cranksets on

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I was obviously not paying attention properly on my last pre lockdown bike shop hop...... I was certain most of the gravel bikes I saw had SLX groupsets, but googling now, I see, like jewbacca has mentioned most of them that run shimano are on 105 with 46 or larger cranksets

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I have GRX800 running 42 crank with 11/42 at the back. XT brake calipers.

 

If you can get to that gearing you should be OK. You spin out at about 50kph, but thats plenty to still have fun on the road, and the 42 at the back makes light of most hills.

Edit: Do expect some big jumps in the gearing, takes some getting used too as a roadie, but seeing hat you are one of the dirty types, you should be ok ;)

 

 

As above, hydrolic brakes are a must.

Edited by Patchelicious
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I have GRX800 running 42 crank with 11/42 at the back. XT brake calipers.

 

If you can get to that gearing you should be OK. You spin out at about 50kph, but thats plenty to still have fun on the road, and the 42 at the back makes light of most hills.

Edit: Do expect some big jumps in the gearing, takes some getting used too as a roadie, but seeing hat you are one of the dirty types, you should be ok ;)

 

 

As above, hydrolic brakes are a must.

This gearing is near perfect,have almost the same except in Sram ...so 10/42. Spin out at about 50pkh as well, but seldom need this speed even when just connecting off-road paths .

 

Like patch says the only downside could be the jump in gears sometimes.But it’s not a deal breaker by any means and it’s not normally to long you find yourself in the less than perfect gear . And you will have a great climbing gear ????????

 

Definitely hydraulic brakes,no doubt !

Edited by Pikey
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This gearing is near perfect,have almost the same except in Sram ...so 10/42. Spin out at about 50pkh as well, but seldom need this speed even when just connecting off-road paths .

 

Like patch says the only downside could be the jump in gears sometimes.But it’s not a deal breaker by any means and it’s not normally to long you find yourself in the less than perfect gear . And you will have a great climbing gear

 

Definitely hydraulic brakes,no doubt !

Fiona now on SRAM? 

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Fiona now on SRAM?

 

No,sold Fiona just before race to the sun last year, built the Niner RLT.

Think Fiona came 3rd as well ????

 

 

Did you see the photo I posted recently in “where has your bike taken you today “ of Fiona’s test ride?

post-51529-0-33617000-1587408493_thumb.jpeg

post-51529-0-12546500-1587408512_thumb.jpeg

Edited by Pikey
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