I have been riding for about a year. I ride a trek 1000. I am wanting to learn more about shifting gears and what order. I have 3 ring in front and 8 in back. What I am wanting to know is when is it better to down shift to the middle ring and and higher back gear than to ride in the big gear in front and small lowest in back, then shift to the middle ring and run the gears all the way back to the highest gear?

Thanks

Dave

Check out this gear calculator. It allows you to compare gear combos in gear inches, gain ratios, etc. It may help you make some comparisons and figure out which gears are essentially the same.

https://sheldonbrown.com/gears/

It certainly helps if you know the terrain.

You don't want to use the big-big (or the small-small) combination. So, if you think you're gonna run out of gas before the top of the hill, then I'd say shift to the middle ring earlier. Other than that... don't overanalyze things too much. The worst that'll happen is you'll have to replace your chain sooner rather than later.

Think about your bike as having three gear ranges corresponding to the three front chainrings: one for flatland riding, one for going up steep hills and one for downhills or those two days a year when you have strong tailwinds. Then use the rear shifter to make fine tuning adjustments so that you are pedaling comfortably within those ranges.

Get a 3spd Seriously, use Sheldon's gear calculator, print out the little chart and tape it to the handle bars. We used to do this years ago when we rode 10 speeds it will help you choose the best gear for the terrain at hand and after a while it will become second nature.

Aaron

Well, when bikes were limited to 5 speed rear clusters and 2 chain rings up front, people went through all sorts of esoteric combinations to maximize the number and effectiveness of their gears. But now with most bikes having 9 speed rear clusters, knowing the exact sequence of gears is really not all that necessary. What I do on a triple or double (chain rings the ones up front), is to ride pretty much in one ring and make my shifts on the rear cluster. Here in FL, I stay pretty much in the big ring, avoiding the big ring big cog combination. When I start to bog down, I shift to the small ring. The main thing is to know when to shift from one ring to the other and not worry about it. Of course, if you want to maximize your gears, there is nothing stopping you from getting anaylitical and figuring out your gear inches. I used to type out the gear inches of each gear and display them veritically in two columns (small ring on the right column, big ring on the left). I taped that to my stem so I could know exactly which gear came next in the sequence. I have not done that since clusters went from 7 gears.

Hmmm. The forum ate a couple of posts from last night, including one of mine. Fortunately, others have covered the major points.

Thinking about having three ranges of eight instead of 24-speeds is essential for clearing things up. After all, nobody thinks of a 4x4 as having eight or ten-speeds. We think in terms of 4-wheel high for the roads, and 4-wheel low for off-road and slippery stuff. That's two ranges of four or five gears each.

With my bike and my body and the terrain I typically ride, it works out like this: Middle ring most of the time. Small ring for steep climbs or stiff headwinds. Big ring for downhills and tailwinds. I let my body tell me which gear to use and when within those ranges, and when to move from one range to another. Your bike, terrain and body will likely tell you something different than mine do, but it will be right for you.

Beware of "double-shifting". Bad things happen when you think, "For the next gear, I need to upshift one ring and downshift two cogs" and then try to do both simultaneously. Shift one end first, let that shift complete, then shift the other end.

Slightly off-topic, a technique that helps smooth-out shifting is to "soft-pedal" your shifts. Ease off a little bit on how hard you're pedaling for the half-revolution it takes for the shift. This is because bikes don't have a clutch. Soft-pedaling effectively provides you with one, which makes all shifts smoother.

Interesting idea about soft pedalling.

Interesting question. There are multiple answers.

1. The perfectly smooth shifting pattern
This is based on the concept that you both don't want to shift when gear change is less than 2% and don't want to jump gears with change greater than say 14%. Enter your 3 chainring tooth count on the top list and then enter the tooth count of each spocket in the bottom list. Site is https://www.panix.com/~jbarrm/cycal/cycal.30f.html.

You will have to process the numbers many times to find the ideal pattern.
1.1 remove duplicate gears, change less than 1%
1.2 start from bottom and slowly deselect gears until you find your shifting pattern.
1.3 The answer will involve some number, 2-4 usually, double shifts and require posting a shifting memory card
on your bike where you can refer to it.

2. After you have answer #1, it will usually favor one chainring. Redo the exercise until you have the best options for using
2.1 the low chainring being primary
2.2 the middle chainring being primary
2.3 the high chainring being primary
If you have lots of hills, answer to 2.1 may be best for you. If young and full of muscles, you might like 2.3. For most of us 2.2 will be the best.

3. The practical shifting pattern.
This approach say, forget double shifting as much as possible and forget a shifting index card. Ride in the middle chainring as much as possible and only downshift when hills are too steep or upshift when downhills run away with your legs. Just for fun, use the above site, your standard chainrings and try switching in different cassettes. Then look at just the middle ring and see the %change between gears and total range of gears each cassette gives you. For example an 11-34 gives you a wide range of speeds without shifting, but at a cost of harder changes between gears. A 12-23 gives you a narrower range of speeds, but shifting is like cutting butter with a hot knife.

Interesting question. There are multiple answers.

1. The perfectly smooth shifting pattern
This is based on the concept that you both don't want to shift when gear change is less than 2% and don't want to jump gears with change greater than say 14%. Enter your 3 chainring tooth count on the top list and then enter the tooth count of each spocket in the bottom list. Site is https://www.panix.com/~jbarrm/cycal/cycal.30f.html.

You will have to process the numbers many times to find the ideal pattern.
1.1 remove duplicate gears, change less than 1%
1.2 start from bottom and slowly deselect gears until you find your shifting pattern.
1.3 The answer will involve some number, 2-4 usually, double shifts and require posting a shifting memory card
on your bike where you can refer to it.

2. After you have answer #1, it will usually favor one chainring. Redo the exercise until you have the best options for using
2.1 the low chainring being primary
2.2 the middle chainring being primary
2.3 the high chainring being primary
If you have lots of hills, answer to 2.1 may be best for you. If young and full of muscles, you might like 2.3. For most of us 2.2 will be the best.

3. The practical shifting pattern.
This approach say, forget double shifting as much as possible and forget a shifting index card. Ride in the middle chainring as much as possible and only downshift when hills are too steep or upshift when downhills run away with your legs. Just for fun, use the above site, your standard chainrings and try switching in different cassettes. Then look at just the middle ring and see the %change between gears and total range of gears each cassette gives you. For example an 11-34 gives you a wide range of speeds without shifting, but at a cost of harder changes between gears. A 12-23 gives you a narrower range of speeds, but shifting is like cutting butter with a hot knife.

Well, you can plug in your gears' teeth-count into Sheldon's calculator. Then you can draw in a shift-pattern for your particular bike. Similar to this one:



You'll find that most "24-speed" or more modern 27/30-spd drivetrains only have 12-17 unique gear-ratios.

Sheldon doesn't work for you. The basic problem is your cassette is not friendly to your knees. It has 2 knee unfriendly shifts: one at 17% and one at 14%. Here are the gory details. [guessing on teeth, as sram doesn't give exact teeth count. Of course, you can count the teeth to verify]

Gears: 42 12-13-14-16-18-21-23-26
--- ------- -------- ---------
SP CRxFW GI GIdf
--- ------- -------- ---------
1> 42x26 43.13 13.04%
2> 42x23 48.76 9.52%
3> 42x21 53.4 16.67%
4> 42x18 62.3 12.50%
5> 42x16 70.09 14.29%
6> 42x14 80.1 7.69%
7> 42x13 86.26 8.33%
8> 42x12 93.45 0.00%


So here are your best shifts, notice this sequence gets rid of the 17% shift.

Gears: 30/42/52 12-13-14-16-18-21-23-26
--- ------- -------- ---------
SP CRxFW GI GIdf
--- ------- -------- ---------
1> 30x26 30.81 13.04%
2> 30x23 34.83 9.52%
3> 30x21 38.14 13.08%
6> 42x21 53.4 7.14%
7> 30x14 57.21 8.89%
8> 42x18 62.3 12.50%
9> 42x16 70.09 14.29%
10> 42x14 80.1 8.33%
11> 52x16 86.77 14.29%
12> 52x14 99.17 7.69%
13> 52x13 106.8 8.33%
14> 52x12 115.7 0.00%

All the rear gears are safe on the middle front chainring. You should avoid the big rear gears when on the small front, and the small rear gears when on the big front.

The easiest way to do that is to stay on the middle the bulk of your time. Shift to the small front if you need something easier, and to the big rear if you're spun out.

Ericqu and retro grouch said it best. Middle (front) chainring most of the time for flattish areas.

If its any conslolation, many people take a long time to get used to all the gear possibilities they have. But if you pay attention to different types of terrain and slopes, you'll get it down in no time.