"Gearing" up for the Mountains!

[Cataboo]

You could also change the front chain ring to a 34 instead of a 36 - most compact cranks are 50x34.


And yes - switching to an 11-28 will make a huge difference. I used to run a 50-34 with a 11-25 and just switched to a 11-28 this spring. I take a lot of hills in my big chain ring now instead of switching to the small one, last year I'd switch to my small one.

If you go on Sheldon brown's site, you can use the gear calculator to calculate how many gear inches or whatever you gain - if those numbers are meaningful for you.

[VeloMel]

You could also change the front chain ring to a 34 instead of a 36 - most compact cranks are 50x34.


And yes - switching to an 11-28 will make a huge difference. I used to run a 50-34 with a 11-25 and just switched to a 11-28 this spring. I take a lot of hills in my big chain ring now instead of switching to the small one, last year I'd switch to my small one.

If you go on Sheldon brown's site, you can use the gear calculator to calculate how many gear inches or whatever you gain - if those numbers are meaningful for you.

I can change out just one chain ring? Wow I learned something new today! If I change out my cassette will I have to change the deurailler (sp?) And chain too?

[Veronica]

If I change out my cassette will I have to change the deurailler (sp?) And chain too?

Depends on what you have on your bike.

I've been looking into changing the 12 - 25 I have on my Cervelo for an 11 - 32. I can manage a 6 mile 5% average grade with it, as is. But on a longer ride, with multiple climbs and anything more than 5%... my knees scream at me. I need to change my derailleur and my chain to switch my cassette. Currently I have SRAM Force on my bike. I need to move to a mid size derailleur to have room for the larger cassette. So, I'll be putting a mid size SRAM Apex derailleur on.

Veronica

[Cataboo]

I can change out just one chain ring? Wow I learned something new today! If I change out my cassette will I have to change the deurailler (sp?) And chain too?

You'd have to check your cranks, but i think probably you can just change the 1 chain ring.

If you change out your cassette, you're supposed to get a new chain. Your rear derailleur can probably handle the 11-28 no problem, because my short cage ultegra one did on mine - but there's a slight chance you'll have to get a long cage rear derailleur.

[carinapir]

I can change out just one chain ring? Wow I learned something new today! If I change out my cassette will I have to change the deurailler (sp?) And chain too?

No, I think you have to change the whole cassette but others might know more about that. I was just referring to the fact that what you will really notice is the new 28 teeth cog because the rest of the gearing on the 11x28 will be very similar to your current cassette.

For example, your 12x25 cassette is probably 12-13-14-15-16-17-19-21-23-25.

Those numbers represent the teeth on each cog.

When you switch to the 11x28 you might get, lets say:
11-13-15-16-17-19-21-22-25-28

I don't know for sure which 10 cogs you will get (I just guessed at those above) but you as you can see, much of the gearing will be identical to what you already have, what you will really notice is the 28.

Also, looking at Sheldon Brown's site and the gain ratios that different front chain rings and different rear cassettes would produce will show you that all these set ups will have lots of overlaying gears. You just need to figure out which hard gears you need for speed and which light gears you need for climbing based on your experience with hills and your current gearing.

I'm not sure if you would have to change derailleur or chain. I'm not knowledgeable enough.

[Eden]

And yes - switching to an 11-28 will make a huge difference. I used to run a 50-34 with a 11-25 and just switched to a 11-28 this spring. I take a lot of hills in my big chain ring now instead of switching to the small one, last year I'd switch to my small one.

Cross chaining like that is a bad habit..... even if you don't hear that nasty grinding noise its hard on the components and makes it more likely you'll drop your chain when you do shift.

[OakLeaf]

Just to clear up:

Chainrings are the cogs in the front. You can buy and change those individually.

Cassette is the collection of cogs and spacers in the rear. For Shimano cassettes (and I think it's the same with other brands), the larger 3-4 cogs are one piece, and the smaller ones are loose. So you can change the smaller cogs (taller gears) individually, BUT they're not sold individually, so you would have to find a shop or a friend you could swap with, if you wanted custom gearing. Also, not all cogs can necessarily go in all positions on a given cassette.

Going from a 25T rear to 27 makes a huge difference to me on the steeper hills.

Do check your derailleur compatibility, although I think any cage that can accommodate 25T will handle 28? You'll probably need to adjust your B-screw if you make this change.


Also, I haven't noticed any ill effects or increased wear from using the same chain length with both. Technically I should probably be using one more link with the 27 than with the 25, but my long cage derailleur is big enough to accommodate it. If I were going to make a permanent change, or swapping back and forth with a larger gear difference (as I plan to replace my 11-25 with an 11-23 as soon as it wears out), then I would/will have to use two different chains as well. How badly you need to change your chain length probably depends on your chainstay length and derailleur cage size. Park Tool has a couple of methods for determining chain length.

If you're making a permanent gearing change but decide that you can keep your old chain until it wears out, then don't forget to make your new chain longer when you do replace it. If it were me, I'd put a note on my chain tool so I wouldn't forget.