benvrackie

I currently have a low gear of 30 front ring 25 rear cassette. Will changing to a rear cassette with
32 make a significant difference on hills of 10 - 20%. ? I love doing some good hill routes but they get
tougher every year .

maddmaxx 

I assume that with your current gearing that you are talking about a road bike. If so you will need to change the rear derailleur over to an MTB style to accomodate the 32 on the cassette. If your control group is currently Shimano, then that's all you will have to do.

10 Wheels

With a triple go to a 24T Small Ring

Jet Travis

Yes, it will make a difference--and the low front ring will definitely help, too. As someone who rides in events with names like The Blue Ridge Extreme, I am not too proud ride a super low bailout gear, but I am too stubborn to stop while going up (unless I fall over, always a possibility) or walk a hill.

Hermes

Yes. My question is do you climb those hills now and how long are they?

benvrackie

Yes I still cycle the hills the longest at an average of maybe 8- 10% over 2 - 3 miles
with 20% and 16% bits. I get back trouble now and then and the steep bits don't help.
I just wanted something a bit easier.

stapfam

Unfortunately probably not. It will require a long reach rear derailler if you do not have one already- and a longer chain.

benvrackie

Yes Stepfam that's exactly it 11 - 32 cassette, new rear mech with longer reach and new chain,
I'm hoping it'll make a difference just wondered how significant it would be. I guess I could go to 22
on the front but don't think I'll need to.

BluesDawg

Calculate the gear inches and you'll see that yes, this will make a significant difference in climbing those hills.

BengeBoy 

Benrackie,

I am one of the old fogies who prefers to understand gearing in terms of gear inches instead of "what cogs/cassette do I need."

Go find Sheldon Brown's gear calculator on the web. Then figure out what combination of chainrings / cassette will give you a low gear between 20 and 25 gear inches. That will get you up anything, as long as you are not heavily loaded. If you are touring and carrying a load, you need to go lower, at least down to 20 gear inches.

Then back your way into the cheapest answer.

- It might be switching to a smaller chainring up front, if your chainset/crankset can handle it.
- Or, in the rear, switching to a bigger cassette + long cage rear derailleur.

If you want to solve this problem forever, get a crankset up front that can take an inner chainring as small as 24 or 26 teeth. Then, put on a mountain bike rear derailleur in the rear and get a wide-range Shimano Cassette that goes up to 34. Depending on the size of wheel you have and the length of your crankarms, you're down around 20 gear inches or lower.

That's it: you'll likely never need lower gears as long as you live.



Playing around with a Gear Calculator will also give you a feel for "how much easier will it be." Put in your current gearing, and then figure out how much lower the new gearing will be. If all you did is switch from a cassette that goes up to 25 to a cassette that goes up to 32 it will probably feel like you have at least "two more gears" next time you climb a hill.

stapfam

If you are "struggling" with 30/25- then putting a 28 on the front would probably be the cheapest option. You could almost go to a 26 but then could have a few Changing problems. Take it this is 9speed and from experience- get the LX cassette. Cheaper than the XT- stronger and not much extra weight.

And as to difference- 30/32 on a road bike and you will be able to climb walls.

Hermes

That is what I suspected. It is hard to say if the lower gearing will make any difference with respect to back pain. It may not - YMMV. You may want to try a 12/27 and get an easier gear. You will notice the difference between 25 and 27 on steeper terrain and it will reduce the forces in your back a little.

I see guys spinning really low gears up climbs i.e. 22 front chainrings. It is okay but they go so slow up the steeper sections they start to weave / wobble. I passed a bent the other day on a switchback with a 20% grade. He was all over the road spinning like crazy but not going anywhere. I had to time my pass with the direction of the wobble. I was afraid he would crash into me. And spinning really low gears means you are on the climb a lot longer which may not be good for your back either.

I suggest a little lower gearing because it sounds like you are doing fine right now.

BengeBoy 

I have to say that I much more frequently see the opposite, especially on organized rides.

People with standard road bike doubles (52/39 chainrings) and standard cassettes, s-l-o-w-l-y grinding their way up hills, or getting off and walking.

10 days ago was the annual "first big ride of the year" in Seattle, the Chilly Hilly, and I saw hundreds of riders "stuck" on hills, not able to push the gears they had. The folks who were going fastest were spinning, not mashing.

I realize that really strong riders can fly up hills on anything - but I have rarely seen average enthusiasts regret having low gears in super-hilly conditions.

Sheldon's gear calculator also allows one to see see what MPH you generate at various cadences. It would be silly to have gearing that takes you down to 1 or 2 mph, but with a cadence of 60 or so going up a hill, having a low gear down around 20 to 25 gear inches does not get you that low.

benvrackie

Thanks for that everyone. Isn't the BF just the best for getting good advice and info.