Best gearing to climb the big mountains in France???

[whitey]

I'm going to France later in the year do some touring which will include all the big cols in France.

I have just switched to a 50/34 compact crankset with a 12-25 cluster. This has made a big difference, but thinking I may need an extra gear or two when I go over.

Options are
12-27
12-28
12-32

My plan was to grab a 12-27, I rolled up Macquarie Pass the other day OK, its a decent ascent so i'm not sure I need the 28 or 32. Also wondering if I need a longer chain for the 12-32?

Any thoughts?

[gururug]

Depends on your fitness, 28 ( +34 ) is good for most hills in sydney for average fitness. Touring is a different style of riding, i'd be going for the biggest range I could. I have no need for a triple front in Sydney but i'd seriously consider one if touring in the french alps.

Yes, you'll probably need a few extra links ( or new chain ) for if you step up to 32.

[silkishuge]

I caount myself a reasonable climber. I have never cycled the big mountains in France, but I have done a bit of climbing up a number of mountains in Japan, comparable to France I believe and I strongly believe that better safe than sorry. I would have enjoyed the rides alot more if I had an extra gear to pedal over the top. 1st mountain okay, second one ouch, 3rd one and I thought I was in agony. I was still in serious hurt the next day and it only got worst during the 3rd day. I was glad the 4th day was all down hill. My 2 cents
Enjoy the trip
Jon

[toolonglegs]

I am not climber at all but I can get over any of the well known mountains in France with a compact crankset and 27 or 28.. only once was that not the case, hitting ventoux after 150 km in 35° heat... But that was possibly more down to a hunger flat than my gearing… So as always it depends

[scirocco]

Having ridden most of the famous climbs in France, I can safely say that no-one ever, ever, ever comes out complaining that their gearing was too low.

All joking aside, you don't too often get steeper than 10.5% or so and even that gradient only occurs in patches. Most moderately fit recreational riders should get by on a 34T compact double with a 28T rear cog. If you're a little stronger a 25T will be okay. But you probably won't be spinning that at 90 rpm, so if you don't like grinding at 60 rpm for long periods then consider a MTB RD and a Tiagra 12-30T cassette.

[donncha]

I went over a couple of years ago with a compact and 28 and it was OK.

Going again in June and taking a 32 this time, specifically for the last col on three col days.

[whitey]

Donncha. I think your point on the last col of the day is pushing me to the 32.

[donncha]

Just be aware that you'll need a longer RD as well. Normal road RDs only support up to 28 or so. SRAM have a longer Apex RD and Shimano have some options as well.

[silkishuge]

Donncha. I think your point on the last col of the day is pushing me to the 32.

Good choice. If you are climbing 2000-4000m a day, the third day will be quite painful. I was really sore on day 3 morning but still completed 10km ascent all up after day 3. You will definitely not regret the extra gearing. Don't forget winds on the flats can be as bad as climbs so you may not get rest in between climbs. I remember riding through a 40km wind tunnel between 2 climbs and it was demoralising when I arrived at the bottom of the next climb.

Jon

[clackers]

Just be aware that you'll need a longer RD as well. Normal road RDs only support up to 28 or so. SRAM have a longer Apex RD and Shimano have some options as well.

I've got a medium sized 105 RD cage and it takes the Apex 12-32 cassette just fine. Fantastic for preserving the knees!

[WestcoastPete]

By touring do you mean just cruising around or will you be carrying a load?

[Ross]

I went over a few years ago and had standard 39/53 on front with 12-27 on rear. Bike was pretty light though, just over 7kg. Wasn't carrying any luggage, just a couple of bidons and a frame pump. I found the hills weren't that steep they just go on for 20km or more!

My other bike has compact cranks with 12-25 and this gearing is a bit lower than 39-53 and 12-27.

[MichaelB]

To me, one thing that would dictate a big granny gear (28 or 32) is the LENGTH of the climbs, rather than the grade.

7% for 5km is wholly different to 20km at the same gradient.

At some stage in the next few years, I want to head over and do some climbs, and one of them is the Passo de Stelvio, and that is 24.3km (AT) 7.4% (Prato side) or 21.5km (AT) 7.1% from Bormio.


The other thing to consider is that for the example below, the 19th & 20th km average 10.7% and 12.1%, but it is the higher altitude as well that will have an effect. Something we just don't get here.

Stelvio via Prato gradient map



Stelvio via Bormio gradient map




I'd do a 34/32 combo just to have that final bailout gear, but would use the 28 most of the time.

[Daccordi Rider]

I did a tour of France and Italy last year, including The Stelvio, Galibier, Ventoux, Huez etc. I used a 34/25 and found that fine. That being said if there was a 27 on the bike I would have been tempted to use it a few times. Depends on the person though, weight, age, fitness. Have a great trip.

[MichaelB]

I did a tour of France and Italy last year, including The Stelvio, Galibier, Ventoux, Huez etc. I used a 34/25 and found that fine. That being said if there was a 27 on the bike I would have been tempted to use it a few times. Depends on the person though, weight, age, fitness. Have a great trip.

Says a mountain goat that weighs 60kg wrining wet ....

Bastard ...

[Daccordi Rider]

I did a tour of France and Italy last year, including The Stelvio, Galibier, Ventoux, Huez etc. I used a 34/25 and found that fine. That being said if there was a 27 on the bike I would have been tempted to use it a few times. Depends on the person though, weight, age, fitness. Have a great trip.

Says a mountain goat that weighs 60kg wrining wet ....

Bastard ...

69 actually.....

[MichaelB]

....Says a mountain goat that weighs 60kg wringing wet ....

Bastard ...

69 actually..... [/quote]

I s'pose that includes the bike .....

[Strawburger]

Don't forget winds on the flats can be as bad as climbs so you may not get rest in between climbs. I remember riding through a 40km wind tunnel between 2 climbs and it was demoralising when I arrived at the bottom of the next climb.

+1

Don't underestimate the winds especially on unprotected climbs.I ran out of gears going up Ventoux with a triple front and 28 rear with 100km/hr headwind on what was a mild day at the base of the climb.

[Daccordi Rider]

Yeh, I drove up the next day after riding it in pouring rain. It was so windy I saw 2 people blown off their bikes. No gear was going to help them that day.

[rustychisel]

Don't forget winds on the flats can be as bad as climbs so you may not get rest in between climbs. I remember riding through a 40km wind tunnel between 2 climbs and it was demoralising when I arrived at the bottom of the next climb.

+1

Don't underestimate the winds especially on unprotected climbs.I ran out of gears going up Ventoux with a triple front and 28 rear with 100km/hr headwind on what was a mild day at the base of the climb.

I got murdered on Ventoux on a 35º day by the mistral riding a borrowed bike with low 39 x 25. At the very least I would go with a 34 x 26 or 27.

[rustychisel]

Don't forget winds on the flats can be as bad as climbs so you may not get rest in between climbs. I remember riding through a 40km wind tunnel between 2 climbs and it was demoralising when I arrived at the bottom of the next climb.

+1

Don't underestimate the winds especially on unprotected climbs.I ran out of gears going up Ventoux with a triple front and 28 rear with 100km/hr headwind on what was a mild day at the base of the climb.

I got murdered on Ventoux on a 35º day by the mistral riding a borrowed bike with low 39 x 25. At the very least I would go with a 34 x 26 or 27.

In fact, beg borrow or steal a copy of Tim Moore's book 'French Revolutions'. There is no finer book to get you in the head space.

[Nikolai]

In not so distant past, men were riding these climbs (not all were paved) on 48x21. Even in my time, a 42x21 was the lowest you could go as a matter of standard. As someone already mentioned, they're not that steep these climbs. Long, yes, but not too steep. If you want to crawl up those mountains instead of riding, then I guess yes, get a mountain bike kind of gear ratio.

[MREJ]

Get a 28 at least. I rode a few decent alps last year in Europe. I put a 28 on my compact Ultegra drivetrain with no adaptation of chain or derailleur. A 25 would have been manageable, but it was better to have the easier option available. On the long stretches, it's nice to sit there and not have to grind so much.

The only comparable climbing I have found in mainland Australia is around Bright. If you get a chance to ride Hotham, Falls and Buffalo, it'll give you a good measure. I've done these with the 25 but took the 28 there this year, after seeing how it helped in Europe.

Macquarie Pass and the climbs around Berry are similar in gradient and feel to Euro classics, but shorter. They're the best training close to Sydney, in my view. Just do repeats!

[whitey]

I'll be averaging 2000m climbing a day with up to 3500m on the big days.

I will check out what length RD cage is, if its Medium I might get away with the 32 otherwise I'll probably settle for 12-28.

In fact, beg borrow or steal a copy of Tim Moore's book 'French Revolutions'. There is no finer book to get you in the head space.

thanks for the suggestion, will look into it.

[Bentnose]

Get a 28 at least. I rode a few decent alps last year in Europe. I put a 28 on my compact Ultegra drivetrain with no adaptation of chain or derailleur. A 25 would have been manageable, but it was better to have the easier option available. On the long stretches, it's nice to sit there and not have to grind so much.

The only comparable climbing I have found in mainland Australia is around Bright. If you get a chance to ride Hotham, Falls and Buffalo, it'll give you a good measure. I've done these with the 25 but took the 28 there this year, after seeing how it helped in Europe.

Macquarie Pass and the climbs around Berry are similar in gradient and feel to Euro classics, but shorter. They're the best training close to Sydney, in my view. Just do repeats!

That's a good idea, I've done a few rides around the area up Mount Buffalo from Ovens, another day Hotham from Harrietville, another day Ovens across the Toowonga Gap up Falls Creek, then back through Happy Valley this one was 179km. I was with Phil Anderson and Simon Gerrans on a training camp and Phil said that they compare favourably to the big climbs in the tour. I did all of those on a 42/23 and didn't have any issues, pretty sure I was seated and spinning most of the time, but then I was about 15 years younger, 10Kg lighter and infinitely fitter, a lot depends on the rider.