Tämä asiakirja on saatavilla myös suomeksi. Dieses Dokument ist auch auf Deutsch erhältlich.
The 63-speed transmission of my do-it-yourself bike with electric gear and trailer is a hybrid:
Sram DualDrive)
The electronic transmission should be very rare. Its principle of operation can be seen in Figure 1 on the page http://www.bsn.com/Cycling/articles/browning.html, which discusses an automatic bicycle transmission.
Now there are as many as 3×3×7=63 gear combinations on the bicycle (or 57, if I avoid the simultaneous use of the biggest or smallest gears). However, there are only 42 (or 40) distinct transmission ratios. The following table lists all 57 gear combinations in ascending order of transmission ratio:
| Transmission ratio | Crank wheel | Sprocket wheel | Planet |
|---|---|---|---|
| 0.75 | 28 | 28 | 3/4 |
| 0.875 | 28 | 24 | 3/4 |
| 1 | 28 | 28 | 1 |
| 1 | 28 | 21 | 3/4 |
| 1.018 | 38 | 28 | 3/4 |
| 1.167 | 28 | 24 | 1 |
| 1.167 | 28 | 18 | 3/4 |
| 1.188 | 38 | 24 | 3/4 |
| 1.313 | 28 | 16 | 3/4 |
| 1.333 | 28 | 28 | 4/3 |
| 1.333 | 28 | 21 | 1 |
| 1.357 | 38 | 28 | 1 |
| 1.357 | 38 | 21 | 3/4 |
| 1.5 | 48 | 24 | 3/4 |
| 1.5 | 28 | 14 | 3/4 |
| 1.556 | 28 | 24 | 4/3 |
| 1.556 | 28 | 18 | 1 |
| 1.583 | 38 | 24 | 1 |
| 1.583 | 38 | 18 | 3/4 |
| 1.714 | 48 | 21 | 3/4 |
| 1.75 | 28 | 16 | 1 |
| 1.778 | 28 | 21 | 4/3 |
| 1.781 | 38 | 16 | 3/4 |
| 1.810 | 38 | 28 | 4/3 |
| 1.810 | 38 | 21 | 1 |
| 2 | 48 | 24 | 1 |
| 2 | 48 | 18 | 3/4 |
| 2 | 28 | 14 | 1 |
| 2.036 | 38 | 14 | 3/4 |
| 2.074 | 28 | 18 | 4/3 |
| 2.111 | 38 | 24 | 4/3 |
| 2.111 | 38 | 18 | 1 |
| 2.25 | 48 | 16 | 3/4 |
| 2.286 | 48 | 21 | 1 |
| 2.333 | 28 | 16 | 4/3 |
| 2.375 | 38 | 16 | 1 |
| 2.375 | 38 | 12 | 3/4 |
| 2.413 | 38 | 21 | 4/3 |
| 2.571 | 48 | 14 | 3/4 |
| 2.667 | 48 | 24 | 4/3 |
| 2.667 | 48 | 18 | 1 |
| 2.667 | 28 | 14 | 4/3 |
| 2.714 | 38 | 14 | 1 |
| 2.815 | 38 | 18 | 4/3 |
| 3 | 48 | 16 | 1 |
| 3 | 48 | 12 | 3/4 |
| 3.048 | 48 | 21 | 4/3 |
| 3.167 | 38 | 16 | 4/3 |
| 3.167 | 38 | 12 | 1 |
| 3.429 | 48 | 14 | 1 |
| 3.556 | 48 | 18 | 4/3 |
| 3.619 | 38 | 14 | 4/3 |
| 4 | 48 | 16 | 4/3 |
| 4 | 48 | 12 | 1 |
| 4.222 | 38 | 12 | 4/3 |
| 4.571 | 48 | 14 | 4/3 |
| 5.333 | 48 | 12 | 4/3 |
The table was generated with a short Perl script written by me.
Using 28-622 tires, one revolution of the rear wheel corresponds to about 2.13 meters. At 60 rpm, the bicycle will make 5.8 km/h (walking pace) on the smallest gear and 40.9 km/h on the biggest gear. When needed, the bike can make 70‒80 kilometers per hour, if enough power is available.