Choosing gearing?

[tylercheung]

Just perusing crank and cassette sizes, this is prob bicycling 101. But how do ppl usually choose their crank and cassette sizes for a, say, road touring or a fasting road bike? Historically I had been using 170 mm compact crank w 11-32 forever "just because" although I guess a lot of bikes have standard 53 crank w 11-25 or something like that. Is there a "good enough for most people" crank/cassette combo? Do I have to plug in numbers in the big scary Sheldon Brown calculator?
Before e

[palincss]

Originally Posted by tylercheung

Just perusing crank and cassette sizes, this is prob bicycling 101. But how do ppl usually choose their crank and cassette sizes for a, say, road touring or a fasting road bike? Historically I had been using 170 mm compact crank w 11-32 forever "just because" although I guess a lot of bikes have standard 53 crank w 11-25 or something like that. Is there a "good enough for most people" crank/cassette combo? Do I have to plug in numbers in the big scary Sheldon Brown calculator?
Before e

There's nothing scary about Sheldon's gearing calculator. Without a basic understanding of gearing you don't have the tools necessary to intelligently choose your optimum gearing, so figure it out. Put in your current gearing, using gear inches not gain ratios. There's a select list on the form.

Then when you ride, actually pay attention to what gears you are using. Note what low gear you need for what kind of hill. Note what high gears you actually use. Understand it in gear inches, because that's independent of the specific chainring and sprocket size you use to get those gears.

Now that you know what those gears are that you're actually using, read this article from Jan Heine's blog for info on how to best set up your gearing to obtain those gears in the best arrangement.

[bicycletricycle]

Easy, adjust the range so that you occasionally spin the biggest gear and occasionally need the easy gear.

That way you can have the tightest steps in the range you actually use.

Obviously you can achieve the same range with different size rings and cassettes but if you are using off the shelf regular road stuff than there isn't a huge overlap in options.

[regularguy412]

OK. I'll bite. Here's my .02.

I think it helps to know if you're a masher or a spinner, or some of both. Also knowing the terrain you'll be tackling is important.

Many of us here on this ol' board have been riding a long time and we kinda know from experience what will work for us, just 'cuz we've been down that road before. To that end, we also kinda know what kind of heart rate/wattage we can do for a given length of time.

All of this goes into choosing gearing and crank length.

I can volunteer what helped me:

For the first 7 years of my racing life, I rode 170mm cranks, 52/42 rings and 12-23 cassettes -- mostly 'cuz that was what came on my first 'good' bike back in 1988,, and I didn't really know any better. All that changed when I got my first 'real' fit when I purchased my first Serotta. I went to 172.5 cranks -- not a big change, but they sure worked better for me. By that time, the 'norm' for racers was 53/39 and 12 or 11-25.

I'm still on the 172.5 cranks and the 11-23 or 12-25 cassettes with 53/39 rings. But around here there are not really any long demanding climbs.

If possible, you might borrow a longer length crank set and install it. See how it goes using your current gearing. Only change one factor at a time. Helps to better see what is working and what isn't.

MIke in AR

[kppolich]

Briefly, not to offend anyone

Average 53/39 with 11-25
Old guys 50/34 with 11-32
Tweeners with climbs 52/36 with 12-28
Flat landers with legs 55/39 with 11-23

My TT bike has 53/39 and 11-28

Cross bike has 40T and 11-32
Road bike has 48T and 11-32

All 172.5's

[John H.]

Formulas don't really apply.
You should select your gearing based on your own preferences.
Do you have a low enough gear to climb your preferred climbs at your preferred pace and cadence?
Some riders dislike climbs because they are over geared- so they have to go max effort up anything that is more than a couple of minutes long.
On the other hand, if you never use your 32- maybe you could ride with different or larger gears.

Originally Posted by tylercheung

Just perusing crank and cassette sizes, this is prob bicycling 101. But how do ppl usually choose their crank and cassette sizes for a, say, road touring or a fasting road bike? Historically I had been using 170 mm compact crank w 11-32 forever "just because" although I guess a lot of bikes have standard 53 crank w 11-25 or something like that. Is there a "good enough for most people" crank/cassette combo? Do I have to plug in numbers in the big scary Sheldon Brown calculator?
Before e

[doomridesout]

If you're in LA and you actually go into the mountains don't listen to guys from the Midwest. I used to live in Kansas, rode 53/39- 12-25, it was great. Then I moved to the West Coast and knew I had to go compact if I wanted to actually go anywhere. Mid compact is really good if you don't have too many steep ramps on your regular rides.

[shovelhd]

If you don't really know what you'll need, go conservative with a compact. You can always turn a compact into a mid compact with a chainring swap. You can't turn a standard into a compact anything.

[Black Dog]

Go with a 50-34. If you need a big gear a 50 x 11 is bigger than a 53 x 12! You will have all your bases covered; just get a 11-28 or larger cassette and there is not much you can not get up or down. There is a lot of humming and hawing over a simple practical decision.

[tctyres]

Originally Posted by tylercheung

Is there a "good enough for most people" crank/cassette combo?

As has been said, I think something like a 50-34 on the front with a 12-28 on the rear is the place to start. Adjust from there.

If you have a lot of hills that you ride, choose lower gearing. If you're strong and light, choose higher gearing. If this is for time trialing on flat ground, choose high gearing.

A lot of it is feel, and your tastes can/will evolve, and your choice on which bike or bikes will follow.

As shovelhd told me a month or two ago, optimal gearing is a luxury, not a necessity.

FWIW: Before I buy a cassette or chainring, I always do a bit of staring at Mike Sherman's gear calculator. At some point, these selections are a bit like splitting hairs unless you have a specific thing you want to do in mind. http://home.earthlink.net/~mike.sherman/shift.html I normally want something south of 40 gear inches for climbing and something north of 110 gear inches for descending. Understanding cadence and gearing in the middle is the hard part of this selection.

[.RJ]

Originally Posted by tctyres

If you have a lot of hills that you ride, choose lower gearing. If you're strong and light, choose higher gearing. If this is for time trialing on flat ground, choose high gearing.

I dont understand the latter. How many of us are strong enough to push a 55/11 (or even 53/11) gear on flat ground on a road bike?

The only thing to decide is how tolerant you are of gaps in your cassette gearing, and go from there and choose the chainrings to match the terrain you ride. Unless its gravel/touring/etc then a 50/34 and 11/28 11-speed cassette will get you damn near anywhere and be great to live with.

[ultraman6970]

This.

The other factor is the type of riding you are doing and which are your fav cogs, for the ride I do pretty much I use 3 cogs all the time with either chainring, so as long as i have those 3 or 4 cogs in a cassette I do not care about the other ones too much.

Some guys love 11 and are not even racers, to me 11/12/13 and even 14 are cogs that a rider with good legs and fast cadence would not even need to ride 40 km/h, but smashers loves them because they dont have cadence at all.

Would not surprise that you dont use all the cogs, but depends of topography aswell. Here is kind'a flat, I move to md at the other side of the beltway 34x32 is a must.

Originally Posted by John H.

Formulas don't really apply.
You should select your gearing based on your own preferences.
Do you have a low enough gear to climb your preferred climbs at your preferred pace and cadence?
Some riders dislike climbs because they are over geared- so they have to go max effort up anything that is more than a couple of minutes long.
On the other hand, if you never use your 32- maybe you could ride with different or larger gears.

[tctyres]

Originally Posted by .RJ

I dont understand the latter. How many of us are strong enough to push a 55/11 (or even 53/11) gear on flat ground on a road bike?

The only thing to decide is how tolerant you are of gaps in your cassette gearing, and go from there and choose the chainrings to match the terrain you ride. Unless its gravel/touring/etc then a 50/34 and 11/28 11-speed cassette will get you damn near anywhere and be great to live with.

My logic there is that you're not going to need the 28 to start off, maybe not even a 25, so a 11-23 cassette might be better. Extra gears in the middle of the cassette would help to be able to adjust your cadence and power. Of course, it depends on the course. I'm never going to push a 55/11, but I will push a 53/11. It also depends on whether you're in a team with a strong paceline, what the other riders are pushing, or whether you are solo.

We had a paceline on Saturday that started off with four on a nicely paved road with easy rollers. We dropped one guy, leaving the three of us rotating with short pulls, averaging 25-27 for ~3 miles. It was fast. I needed everything I had in the middle. I sure didn't need anything larger than 23 or my small ring. It all depends on what you're doing or trying to do, that's all.

Edit: I just looked at that Strava section with the fast paceline. 2.8 miles, 25.5 average. Max 29.3. No need for the 11. More in the middle helps, though.

[.RJ]

Originally Posted by tctyres

No need for the 11. More in the middle helps, though.

Agreed. I guess thats where I was going

[parris]

I admit that I like to play around with different gear combo's. When I raced in my early 20's my default was 42/52 and 13/21. I tend to spin so the 52/13 was always good.

My knees and just about everything else likes the wider ranges we have easy access to today. Most of my bikes have either compact or mid compact. This winter I took one of my standard cranks and went with 38/48 thinking that with the cassettes I have I'd be able to get a good enough spread from low to high gearing.

The 2 big reasons I did this were because I just didn't want a good crankset sitting on the shelf and also more importantly although front shifting is really good already I've been thinking that it would be even smoother with a smaller gap.

Cassettes and chainrings don't have to be crazy expensive and having the option's are at least for me a fun part of the game.