Gear ratios

Bianchi Boy

What is the best way to get a lower gear. I currently have a 53-39 chainset and a 12-25 sprocket. What is th best way to go.

1. Compact chainset
2. Triple chainset
3. 12-27 sprocket
4. A combination of the above

I did find some of the Alpine climbs a bit tough in the 39-25

dennisn

For my money I vote compact. 50-34 or 50-36 with an 11-21 great for the flats and 50-34 with a
12-25 or 12-27 great for the big mountains. Then again I'm old but it works great. Wish I
would have had one in my younger days. No complaints.

Dennis Noward

schweiz

I use a triple and a 12-27 (9 spd). Towards the end of a long day (8+ hours in the saddle) in the Alps, the 30/27 gear can be a godsend as you know you can get up anything. I'm 85kg so that's quite a bit of weight to drag up 4000+m in a day. A friend weighs 60kg and sticks with a triple and a 12-25

I know one shop near me (http://www.danischnider.ch/) who claims he won't sell a double or a compact to anyone who wants to go into the mountains unless the specifically ask for it!

Saying that, if you already have a double, the expense of changing to a triple is quite high, so try a compact with a 12-27 first and see how you get on. I reckon I could do just about everything I want to on that set up, but it's nice to know I have the the bail out of 30-27.

unclemalc

Bianchi Boy wrote:

What is the best way to get a lower gear. I currently have a 53-39 chainset and a 12-25 sprocket. What is th best way to go.

1. Compact chainset
2. Triple chainset
3. 12-27 sprocket
4. A combination of the above

I did find some of the Alpine climbs a bit tough in the 39-25

If you can climb even some Alps in 39*25 then a compact 50-34 will get you up those you missed....

schweiz

unclemalc wrote:

If you can climb even some Alps in 39*25 then a compact 50-34 will get you up those you missed....

I did wonder Bianchi's cadence was if he was on a 'real' alpine pass!!

Mossrider

You sound pretty fit with that gearing bianchi boy! I'll echo Dennis. My summer bike (also a bianchi) is fitted with a 50/36 and normally (living in the Pennines) I keep myself fit with a 11/23 rear (roughly equivalent to your current gearing). For holidays (I was in the Alps (Cormet de Roseland, Croix de Fer etc) in September, and I've also used it on Mont Ventoux and Teide on Tenerife) and for sportifs I switch to a 12/25. Not the most generous gearing but just about good enough to get you up anything. I did find another tooth might have been good on occasion (Cormet de Roseland), but I didn't"need" it and I still got up everything in pretty good shape; it would only have slowed me!

It seems to offer a good spread of gears without having the huge jump from a 50 ring to a 34.

Mister W

The cheapest option is to change your cassette. Sheldon Brown has a gear calculator that will show you how much lower this will take you - http://www.sheldonbrown.com/gears/

If you've got Campag then I believe there's a cassette with a 29 although I don't know if this will need a different rear mech.

The next cheapest option is a compact, which you may be able to do by just changing the chainset (depending on your BB and rear mech). It's not difficult to do as long as you've got the right tools.

Changing to a triple is a pain, they're a bit of a git to set up and they're rarely as reliable as a double so I wouldn't recommend going that way.

celbianchi

schweiz wrote:

unclemalc wrote:

If you can climb even some Alps in 39*25 then a compact 50-34 will get you up those you missed....

I did wonder Bianchi's cadence was if he was on a 'real' alpine pass!!

What does his cadence matter? When I come over to the Alps I usually fit a 12/25 to go with a 53/39 up front. I have been over with a 11/23 on a 53/39, and can get up Alpe D'huez as the 3rd climb of the day (e.g after the Izoard and Lauteret, or at after Glandon, Telegraphe, Galibier then D'Huez) in around an hour.

Not everyone spins 85 revs a minute on a climb.

schweiz

celbianchi wrote:

What does his cadence matter? When I come over to the Alps I usually fit a 12/25 to go with a 53/39 up front. I have been over with a 11/23 on a 53/39, and can get up Alpe D'huez as the 3rd climb of the day (e.g after the Izoard and Lauteret, or at after Glandon, Telegraphe, Galibier then D'Huez) in around an hour.

Not everyone spins 85 revs a minute on a climb.

His cadence doesn't really matter, I was merely wondering. I climb at about 70-75rpm and I am just impressed by the fact he (and you for that matter) do Alpine routes with a 39/25 or 39/23. On a 15km+ climb with an average gradient of 8-10% with sections of 18%+ that takes some doing. The equivalent gearing on the inner chainring of my triple (30t) would be around 18 on the back and I couldn't imagine myself doing the harder stuff on that!

I was not having a go or disputing his claim. Like I said, I was merely wondering!

Gav2000

Mister W wrote:

If you've got Campag then I believe there's a cassette with a 29 although I don't know if this will need a different rear mech.

Yes, the 13-29 Campag cassette does need a different rear mech.

I've just added this to a new bike I've built and with a 50/34 compact at the front should give me the range to get up anything without resorting to a triple.

Gav.

celbianchi

schweiz wrote:

celbianchi wrote:

What does his cadence matter? When I come over to the Alps I usually fit a 12/25 to go with a 53/39 up front. I have been over with a 11/23 on a 53/39, and can get up Alpe D'huez as the 3rd climb of the day (e.g after the Izoard and Lauteret, or at after Glandon, Telegraphe, Galibier then D'Huez) in around an hour.

Not everyone spins 85 revs a minute on a climb.

His cadence doesn't really matter, I was merely wondering. I climb at about 70-75rpm and I am just impressed by the fact he (and you for that matter) do Alpine routes with a 39/25 or 39/23. On a 15km+ climb with an average gradient of 8-10% with sections of 18%+ that takes some doing. The equivalent gearing on the inner chainring of my triple (30t) would be around 18 on the back and I couldn't imagine myself doing the harder stuff on that!

I was not having a go or disputing his claim. Like I said, I was merely wondering!

sorry Scweiz, I did not mean to suggest you were doubting or being critical, but you do get a number of people who suggest that if you are not whirring away at 95 rpm up climbs then you are doing it wrong.

It's hourse for courses with climbing and whatever suits your own style. I don't think fitting a 36*27 would make me go any faster as I like to have something to push against.