Following on from my post about identifying Mini drop gears – in particular straight cut drop gears – I came across an interesting article on MiniMania.com. I hope they don’t mind me pinching this information, but I want to just incase they take this article down in the future.
| TYPE | PRIMARY | IDLER | INPUT | RATIO | COMMENTS |
| TRANNEX - | |||||
| 22 | 30 | 25 | 1.136-1 | ||
| 24 | 30 | 24 | 1.0-1 | ||
| 23 | 30 | 23 | 1.0-1 | Extra strong input gear | |
| 24 | 30 | 25 | 1.0416-1 | ||
| 23 | 30 | 24 | 1.0434-1 | ||
| 22 | 30 | 23 | 1.045-1 | Extra strong input gear | |
| 23 | 30 | 25 | 1.0869-1 | ||
| 22 | 30 | 24 | 1.09-1 | ||
| 24 | 30 | 23 | 0.958-1 |
NOTE; All Trannex ratios use same idler gear, so are totally interchangeable with each other. Not interchangeable with other manufacturers. Superior over-all quality makes these Number One.
| TYPE | PRIMARY | IDLER | INPUT | RATIO | COMMENTS |
| ST TRANSMISSIONS & JACK KNIGHT – | |||||
| 24 | 31 | 24 | 1.0-1 | ||
| 23 | 31 | 24 | 1.043-1 | Same idler/input as above | |
| 23 | 30 | 25 | 1.087-1 | Seperate set from above 2 |
Also, an interesting paragraph on the effect of different ratio drop gears on the final drive
Drop gears can be used to fine tune final drive. To assess actual FD, just multiply FD by the drop gear ratio. So a 3.44FD using a 1.0434 drop gear set would give – 3.44 x 1.0434 = 3.59 FD. A glance at the FD table will show this can be used to achieve ratios not available off the shelf.
Finally, I’ve found out that my gearbox uses Tranx (or Trannex) gears, so the table above is proving very helpful in identifying what drop gears I have and which ones I’ll use.
Can’t go a post without a photo, surely? Above is the drop gears I have, and I currently have two primary gears with different amount of teeth on them. I’ve yet to count them though…
Useful, I’ll be needing this soon!