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Does anyone yet make an affordable quad chainring? I would love to see a 4x12 with my staggered cog idea such that all 12 gears are shifted progressively using the 4 chainrings. I haven't yet worked out a spreadsheet for this but I am thinking the chainrings could be something like 20,30,40,50. Each chainring would engage only 3 cogs. I think the "double shifting" would be quite easy. On the gear indicator (1 thru 12), every 3rd gear could be marked with a different color number to indicate to the rider that a "double" shift is required next. Generally when the rider settles into a good pace on reasonably flat pavement, he/she will only be using 1 chainring and using the 3 gears for it to fine tune the cadence. For example, if the chainrings are labelled A,B,C and D and each cog for each of those chainrings is labeled 1 thru 3, someone might be using C2 gear but shift to C1 for a slight headwind and C3 for a slight tailwind.

I think it is a good and interesting idea and would look cool too.

I played around in a spreadsheet and came up with these ratios:

  1. 20/40 = 0.5
  2. 20/33 = 0.61
  3. 20/27 = 0.74
  4. 28/31 = 0.9
  5. 28/26 = 1.09
  6. 28/21 = 1.33
  7. 36/22 = 1.64
  8. 36/18 = 2
  9. 36/15 = 2.4
  10. 44/15 = 2.93
  11. 44/13 = 3.38
  12. 44/11 = 4.00

Notice that the 15 cog repeats cuz the difference between the 36 and 44 chainrings is close enough to 20%.

Also notice the overall spread of the gears is a very wide 8 with a very low 1st gear (0.5) and a reasonably tall high gear (4.0). That should cover almost any situation for the average rider.

Does anyone yet make an affordable quad chainring? I would love to see a 4x12 with my staggered cog idea such that all 12 gears are shifted progressively using the 4 chainrings. I haven't yet worked out a spreadsheet for this but I am thinking the chainrings could be something like 20,30,40,50. Each chainring would engage only 3 cogs. I think the "double shifting" would be quite easy. On the gear indicator (1 thru 12), every 3rd gear could be marked with a different color number to indicate to the rider that a "double" shift is required next. Generally when the rider settles into a good pace on reasonably flat pavement, he/she will only be using 1 chainring and using the 3 gears for it to fine tune the cadence. For example, if the chainrings are labelled A,B,C and D and each cog for each of those chainrings is labeled 1 thru 3, someone might be using C2 gear but shift to C1 for a slight headwind and C3 for a slight tailwind.

I think it is a good and interesting idea and would look cool too.

Does anyone yet make an affordable quad chainring? I would love to see a 4x12 with my staggered cog idea such that all 12 gears are shifted progressively using the 4 chainrings. Each chainring would engage only 3 cogs. I think the "double shifting" would be quite easy. On the gear indicator (1 thru 12), every 3rd gear could be marked with a different color number to indicate to the rider that a "double" shift is required next. Generally when the rider settles into a good pace on reasonably flat pavement, he/she will only be using 1 chainring and using the 3 gears for it to fine tune the cadence. For example, if the chainrings are labelled A,B,C and D and each cog for each of those chainrings is labeled 1 thru 3, someone might be using C2 gear but shift to C1 for a slight headwind and C3 for a slight tailwind.

I think it is a good and interesting idea and would look cool too.

I played around in a spreadsheet and came up with these ratios:

  1. 20/40 = 0.5
  2. 20/33 = 0.61
  3. 20/27 = 0.74
  4. 28/31 = 0.9
  5. 28/26 = 1.09
  6. 28/21 = 1.33
  7. 36/22 = 1.64
  8. 36/18 = 2
  9. 36/15 = 2.4
  10. 44/15 = 2.93
  11. 44/13 = 3.38
  12. 44/11 = 4.00

Notice that the 15 cog repeats cuz the difference between the 36 and 44 chainrings is close enough to 20%.

Also notice the overall spread of the gears is a very wide 8 with a very low 1st gear (0.5) and a reasonably tall high gear (4.0). That should cover almost any situation for the average rider.

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Quad chainring (4x12)?

Does anyone yet make an affordable quad chainring? I would love to see a 4x12 with my staggered cog idea such that all 12 gears are shifted progressively using the 4 chainrings. I haven't yet worked out a spreadsheet for this but I am thinking the chainrings could be something like 20,30,40,50. Each chainring would engage only 3 cogs. I think the "double shifting" would be quite easy. On the gear indicator (1 thru 12), every 3rd gear could be marked with a different color number to indicate to the rider that a "double" shift is required next. Generally when the rider settles into a good pace on reasonably flat pavement, he/she will only be using 1 chainring and using the 3 gears for it to fine tune the cadence. For example, if the chainrings are labelled A,B,C and D and each cog for each of those chainrings is labeled 1 thru 3, someone might be using C2 gear but shift to C1 for a slight headwind and C3 for a slight tailwind.

I think it is a good and interesting idea and would look cool too.