cantdrv55

My bike has 12-25 cassette. Will a 12-27 be a worthy upgrade for climbing?

WheresWaldo

Not enough to make a real difference. I know I tried it. A better solution is going to a compact crankset.

Blue Jays

Hi cantdrv55-

It depends on where you ride, the steepness of the hills, and the duration of the climbing. Have you been reduced to pushing the bike uphill or are you simply finding yourself exhausted at the summit?

~ Blue Jays ~

UmneyDurak

Well... It will get you another ~5rpm. Will it be worth it is up to you. How bad are you suffering on the hills? Better option might be a compact with 12/25 or 12/27.

mezza

An even better solution is find a hill and climb it. Then do it again another day. Then again another day. Then again another day. The start on an even more difficult hill. Keep going like this for several months and soon you'll be climbing hills much better.

Theres no magic bullet. Put in some sweat time.

jschen

Depends. Which category are you in?

a) You don't find yourself wishing for a lower gear. Don't bother with a cassette change.
b) You find yourself wishing for just one more gear. Get the 12-27 cassette.
c) You find yourself really struggling and needing a much lower gear. A 12-27 cassette is only 8% lower gearing. It can't do magic.

Phantoj

It will make a mile-long 10% grade feel like a 1.08-mile-long 9.25% grade.

terrymorse 

I use a 12-27 cassette (and a compact crankset), and I do what most people would consider a lot of climbing. After 4 or 5 hours of climbing in a day, it's nice to be able to reach for those lower gears.

To the OP, if you're not able to maintain at least a 60 cadence on the hills you're climbing, definitely get yourself some lower gears. You're not doing yourself any favors if you're grinding away at a very low cadence.

Patriot

I was going to go inthe same direction as terry. Going to a compact would give you more than going to a 27t cassette.

However, if you did both, a 50/34 CT and a 12-27t cassette, you'd be in the realm of a granny gear, yet still maintaining the implicity of a double.

ovoleg

just practice more, no need to buy gear because you suck at climbing

NFields

I had the same problem a few years ago....I found going to the gym helped more than anything, and working on leg strength.

NFields

substructure

Tell ya what I did - and I really don't know if it's worth it to you, but it made a difference for me.

During the winter months, up until last week, I used a 12-23 with a 52/38 and did a lot of climbing. My commutes have almost 3000 feet of climbing one way. One hill in particular has grades up to 18%. I also carried extra gear like a hydration pack with tools and such. For the first few weeks I could barely make it over my bete noire called Pinnacle Road. My knees kind of hurt a little and it would wear me out real good. I had to stand every time to get over it. Eventually I started climbing it a lot better. Soon I wouldn’t even have to stand.

Then I switched to a 12-27. Man, what a difference. I’m spinning over it with ease. I feel a lot better on climbs and rolling terrain.

So I guess my suggestion is to first try and get stronger on climbs. Also, I am down to below 180. I use to be over 200 lbs. That also made a difference.

GuitarWizard

50/36 compact w/ a 12-27 is a really good setup.

atomship47

but in the meantime......

[sorry for the thread hijack]

i believe mine is a 52/39 11-23 set up. i was thinking of swapping my small chainring for a 36 and cassette for a 12-27.

will i have any mechanical issues with a 52/36? can it even be done?

WheresWaldo

52>36 is a 16T drop, just make sure your front dérailleur can handle that much. For example an Ultegra FD is rated at 15T, Shimano is usually conservative with their ratings, so it probably will work although Shimano will tell you that you may be sacrificing shifting quality.

Also, if you have a Shimano crank with a BCD of 130mm you will not find anything smaller than 38T that will fit on the inside of the crank.

slowandsteady

Well, some people are cranking along at 40 rpms on those big hills and having a smaller gear really saves the knees. Or even worse, the hills are so bad you have to get off and walk. Now what is the point of that?

Once you get into better shape and hit the gym for a few months you can go back to the racing gears. There really is no point in risking injury for 4-6 months while you try to get into better shape.

deskjockey

There are always the 13-25/27 options. Hard to come by, but out there. My LBS convinced me to go this route along a compact FSA SL-K crankset on my recent build based on the time I spend in the 12 (not too often) and the time I spend spinning. The cassette also included another cog to help w/ the spinning (maybe an 18 tooth). Overall, it has been nice, but I haven't determined whether the new ratios have saved me a bit of energy for climbing in the lowest gears.

ovoleg

The fact that you are cranking at 40rpms is the result of a few key mistakes

1) You attempted a hill that is outside your skill level
2) You need to work on your leg strength so that you don't have to crank at 40rpms

slowandsteady

Sometimes all you have to ride is what exists in your area. If you live in the mountains, you can't very well find a nice flat stretch. It doesn't exist. What if you are seriously over weight? You can't just hack off 50 lbs because you are going for a ride. Dieting and weight loss takes many months.

And, of course the person needs to work on leg strength, but that doesn't happen overnight. It happens over a period of months. You have to do something in the mean time to save yourself from injury.

briscoelab

I'd say get a 12-27 and see how it feels. It does provide a slightly lower gear... and it is enough to notice. If you find that you still need something lower, then look at getting a compact. But, a $60 cassette is a hell of a lot cheaper than buying a compact. If the cassette does the job... you win And it never hurts to have an extra cassette hanging around anyhow.

ovoleg

The number of assumptions made is extraordinary. The reason I state this is that alot of new people come on here and they immediately want some extreme cassette range because they can't just breeze through all the hills they see. Face it, hills are going to be tougher than your flat land, you dont need a 27+ cassette to traverse the hills around your area. Start training and riding lowkey grades before you start hitting Everest.

I doubt the OP or many here go outside and see over 5% grades right near them...If not I want your zip code so I can look online. Thank you.

FIVE ONE SIX

a 50-24 with a 11-23 will give you almost the same climbing as a 53-39 with a 12-27, but with a higher top speed, closer gearing and reduced weight...

Socalcycling

yes, and you were one of those who came on here and asked the same question because the 1% grade up Reseda to Rinaldi was busting your balls.

ElJamoquio

15108, where I grew up. Not the city, the township.

superdex

ahem. 80207. For the record, I run 50/34 with 12-27 and 12-28. With those combos I actually want to climb

OP, can you be specific about your troubles? Lots of factors here (as you can see)....