Waiting for the weather to resemble the forecast I started thinking about why my two road bikes gears produced very different shifting combinations. This makes riding and selecting the gear combinations to use with a given cadence to go a certain speed challenging. My desire is to select gears in a similar sequence to ride at similar speeds.

My Lynskey R300 bike’s 52×40 chainrings teamed with a 11×34 rear cassette and 700×33 tires produce speeds different from the Canyon Endurace’s 52×36 chainrings and 11×25 cassette turning 700×28 tires. To compare these setups I turned to gear inches. From Sheldon Brown’s Glossary: “One of the three comprehensive systems for numbering the gear values for bicycle gears. It is the equivalent diameter of the drive wheel on a high-wheel bicycle. When chain-drive “safety” bikes came in, the same system was used, multiplying the drive wheel diameter by the sprocket ratio. It is very easy to calculate: the diameter of the drive wheel, times the size of the front sprocket divided by the size of the rear sprocket. This gives a convenient two- or three-digit number.” The Lynskey and Canyon current gear inch charts.

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Not wanting to change the gearing on the Canyon Endurace because it is my primary bike I looked at several rear cassette options for the Lynskey R300.

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With the different small chainrings different gear inches result with a cassette. In the search for close gear inches and shifting combinations I compared 11×28, 11×30, and 11×25 rear cassettes to the Canyon’s setup. Option 4 and 5 changes the chainring and rear cassette.

In my biking technique for Houston’s flat roads I start off in the small chainring and third cassette gear. On the Canyon Endurace this would be 36×21, producing 45.2 gear inches. For the Lynskey R300 current setup to get a similar pedaling effort I start in the small chainring and fourth cassette gear, 40×25, producing 43.2 gear inches. These are not too far apart but I shift gears at the 1/2 mile mark in my warmup cycle. The 1/2 mile gear combinations: Canyon 36×19 equals 50 gear inches, Lynskey 40×23 equals 47.0 gear inches. At 1 mile I shift again: Canyon 36×17 with 55.9 gear inches, Lynskey 40×21 turning 47.0 gear inches. To go similar speeds the cadence on the Lynskey starts to go faster as the gear inch difference grows. The next shift happens at 2 miles: Canyon 36×16 at 59.4 gear inches, Lynskey 40×19 at 56.8 gear inches narrows the gap some. To recover some of the difference I shift the Lynskey at 3 miles while I hold off on the Canyon to 4 miles. At 3 miles the Lynskey produces 63.5 gear inches from 40×17 gears. The Lynskey uses the 8th rear gear while the Canyon sits at the 6th gear. Mile 4 gets me to a cruising speed that I hold for awhile and shift to these combinations: Canyon 36×15 63.3 gear inches, Lynskey 40×15 72.0 gear inches. When I am ready to speed up I shift to these combinations: Canyon 36×14 67.8 gear inches, Lynskey I shift to the big chainring 52×19 73.9 gear inches. If the headwind isn’t too strong when riding the Canyon I make one more shift to the 36×13 resulting in 73.1 gear inches.

From this comparison the Lynskey gear changes differ by several steps from my base Canyon Endurace shifting pattern. Since I like to think about other things while biking besides shifting patterns I searched for similar patterns.

Looking at the shifting pattern I compared these three. Two do not change the small chainring while the other changes the chainring and rear cassette. The third option costs more because of replacing two components. If I replace two components then I should go with the 36 tooth chainring and 11×25 cassette. The gear inches will still not match because of the different tire sizes.

Canyon 52×36, 11×25 Gear Combination	Gear Inches	Lynskey 52×40, 11×30 Gear Combination	Gear Inches	Lynskey 52×36, 11×25 Gear Combination	Gear Inches
36×25	38.0	40×30	36.0	36×25	38.9
36×23	41.3	40×27	40.0	36×23	42.3
36×21	45.2	40×24	45.0	36×21	46.3
36×19	50.0	40×21	51.4	36×19	51.2
36×17	55.9	40×19	56.8	36×17	57.2
36×16	59.4	40×17	63.5	36×16	60.8
36×15	63.3	40×15	72.0	36×15	64.8
36×14	67.8	40×14	77.1	36×14	69.4
36×13	73.1	40×13	83.1	36×13	74.8
36×12	79.1	40×12	90.0	36×12	81.0
36×11	86.3	40×11	98.2	36×11	88.4

The conclusion: buy the 11×25 Ultegra R8000 rear cassette and 36 tooth chainring. The gear inches will be close and the shifting pattern closer than the current ones. Cost to make the change: $89.