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 08-18-14, 11:11 PM #1 Darth Lefty  Disco Infiltrator Thread Starter     Join Date: May 2013 Location: Orangevale CA Bikes: '76 Paramount, 02 Hardrock, '98 C'Dale XR800, '04 Burley Samba Posts: 7,484 Mentioned: 27 Post(s) Tagged: 0 Thread(s) Quoted: 738 Post(s) Cassette builder spreadsheet I made this spreadsheet to calculate the cog sequence for a cassette. It uses the (speeds-1)th root of the ratio from the top to bottom cog and finds integer cog steps to each next gear. The equations are in a BBCode table below and you should be able to paste it straight into the upper left corner of an Excel worksheet. Feel free to bug check, play, find objections, make improvements. I originally had this starting with the small cog but it sometimes missed by a tooth the final cog. [table="width: 500, class: grid"] [TR] [TD]Cassette builder[/TD] [TD][/TD] [TD][/TD] [TD][/TD] [TD][/TD] [/TR] [TR] [TD]# cogs[/TD] [TD][/TD] [TD]Top[/TD] [TD][/TD] [TD]Bottom[/TD] [/TR] [TR] [TD]8[/TD] [TD]x[/TD] [TD]11[/TD] [TD]to[/TD] [TD]28[/TD] [/TR] [TR] [TD][/TD] [TD][/TD] [TD][/TD] [TD][/TD] [TD][/TD] [/TR] [TR] [TD]ideal ratio[/TD] [TD]=(E3/C3)^(1/(A3-1))[/TD] [TD][/TD] [TD][/TD] [TD][/TD] [/TR] [TR] [TD]gear[/TD] [TD]ideal[/TD] [TD]step[/TD] [TD]cog[/TD] [TD][/TD] [/TR] [TR] [TD][/TD] [TD][/TD] [TD][/TD] [TD][/TD] [TD][/TD] [/TR] [TR] [TD]1[/TD] [TD]=IF(A8<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A8),FALSE)[/TD] [TD][/TD] [TD]=B8[/TD] [TD][/TD] [/TR] [TR] [TD]=A8+1[/TD] [TD]=IF(A9<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A9),FALSE)[/TD] [TD]=IF(B9,ROUND(B9-B8,0))[/TD] [TD]=IF(B9,C9+D8)[/TD] [TD]=IF(B9,D8/D9)[/TD] [/TR] [TR] [TD]=A9+1[/TD] [TD]=IF(A10<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A10),FALSE)[/TD] [TD]=IF(B10,ROUND(B10-B9,0))[/TD] [TD]=IF(B10,C10+D9)[/TD] [TD]=IF(B10,D9/D10)[/TD] [/TR] [TR] [TD]=A10+1[/TD] [TD]=IF(A11<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A11),FALSE)[/TD] [TD]=IF(B11,ROUND(B11-B10,0))[/TD] [TD]=IF(B11,C11+D10)[/TD] [TD]=IF(B11,D10/D11)[/TD] [/TR] [TR] [TD]=A11+1[/TD] [TD]=IF(A12<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A12),FALSE)[/TD] [TD]=IF(B12,ROUND(B12-B11,0))[/TD] [TD]=IF(B12,C12+D11)[/TD] [TD]=IF(B12,D11/D12)[/TD] [/TR] [TR] [TD]=A12+1[/TD] [TD]=IF(A13<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A13),FALSE)[/TD] [TD]=IF(B13,ROUND(B13-B12,0))[/TD] [TD]=IF(B13,C13+D12)[/TD] [TD]=IF(B13,D12/D13)[/TD] [/TR] [TR] [TD]=A13+1[/TD] [TD]=IF(A14<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A14),FALSE)[/TD] [TD]=IF(B14,ROUND(B14-B13,0))[/TD] [TD]=IF(B14,C14+D13)[/TD] [TD]=IF(B14,D13/D14)[/TD] [/TR] [TR] [TD]=A14+1[/TD] [TD]=IF(A15<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A15),FALSE)[/TD] [TD]=IF(B15,ROUND(B15-B14,0))[/TD] [TD]=IF(B15,C15+D14)[/TD] [TD]=IF(B15,D14/D15)[/TD] [/TR] [TR] [TD]=A15+1[/TD] [TD]=IF(A16<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A16),FALSE)[/TD] [TD]=IF(B16,ROUND(B16-B15,0))[/TD] [TD]=IF(B16,C16+D15)[/TD] [TD]=IF(B16,D15/D16)[/TD] [/TR] [TR] [TD]=A16+1[/TD] [TD]=IF(A17<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A17),FALSE)[/TD] [TD]=IF(B17,ROUND(B17-B16,0))[/TD] [TD]=IF(B17,C17+D16)[/TD] [TD]=IF(B17,D16/D17)[/TD] [/TR] [TR] [TD]=A17+1[/TD] [TD]=IF(A18<=\$A\$3,\$C\$3*\$B\$5^(\$A\$3-A18),FALSE)[/TD] [TD]=IF(B18,ROUND(B18-B17,0))[/TD] [TD]=IF(B18,C18+D17)[/TD] [TD]=IF(B18,D17/D18)[/TD] [/TR] [/TABLE] Last edited by Darth Lefty; 08-19-14 at 12:13 AM.
 08-18-14, 11:21 PM #2 Darth Lefty  Disco Infiltrator Thread Starter     Join Date: May 2013 Location: Orangevale CA Bikes: '76 Paramount, 02 Hardrock, '98 C'Dale XR800, '04 Burley Samba Posts: 7,484 Mentioned: 27 Post(s) Tagged: 0 Thread(s) Quoted: 738 Post(s) Here are some funny things I've discovered using this. The sequence this gives is the closest to an exponential line with equal ratio steps. But this is not always the cassette you can buy, and the reason seems to be that there's a more common sequence available. For instance in the example in the first post, an 11-28 cassette commonly found on 24-speed mountain bikes and hybrids usually goes, 11-13-15-17-19-21-24-28 But the spreadsheet shows a sweeter sequence. 11-13-15-17-19-22-25-28 However this sequence does not use the 21-24-28 combination which is found in a lot of cassettes. You can also see that 8x11-30 (and 9x11-34) is really sweet... but 8x11-32 has 21-24-28-32. 25 and 27 basically only ever appear as a bottom gear and you'll never see an odd gear higher. Last edited by Darth Lefty; 08-18-14 at 11:32 PM.
 08-18-14, 11:34 PM #3 CharlyAlfaRomeo Senior Member   Join Date: Sep 2013 Bikes: Posts: 616 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) The "sweeter" sequence is subjective and down to personal taste, I'd rather have the 2 tooth difference of a 19-21 step. I'm always switching between those two gears and wish I could find a 10 speed cassette with a 20 tooth cog. FWIW Campy makes 13-29 road cassettes if you want to throw that in the mix.
 08-18-14, 11:58 PM #4 Darth Lefty  Disco Infiltrator Thread Starter     Join Date: May 2013 Location: Orangevale CA Bikes: '76 Paramount, 02 Hardrock, '98 C'Dale XR800, '04 Burley Samba Posts: 7,484 Mentioned: 27 Post(s) Tagged: 0 Thread(s) Quoted: 738 Post(s) Well, sweeter in that it follows the curve more closely. I wouldn't try to use this to argue with preference.
 08-19-14, 01:02 AM #5 trailangel Senior Member     Join Date: Feb 2014 Location: Pasadena, CA Bikes: Schwinn Varsity Posts: 2,146 Mentioned: 4 Post(s) Tagged: 0 Thread(s) Quoted: 511 Post(s) IMHO you are better off looking at gear inches than ratios. There are not any sweet gears.
08-19-14, 09:44 AM   #6
Darth Lefty
Disco Infiltrator

Join Date: May 2013
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Quote:
 Originally Posted by trailangel IMHO you are better off looking at gear inches than ratios. There are not any sweet gears.
This will do gear inches but it's fairly trivial, I wanted to share something clever.

Edit - sigh - replace all smileys with colon D.
[TABLE="class: grid, width: 500"]
[TR]
[TD][/TD]
[TD]Tire size 700c x 32mm
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]rim mm
[/TD]
[TD]622
[/TD]
[TD]630 (27), 622 (700c), 559 (26 & fat)
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]tire mm
[/TD]
[TD]32
[/TD]
[TD]25 (1), 28 (1.125), 32 (1.25), 38 (1.5), 41, 45 (1.75), 51 (2), 54(2.125), 76 (3), 96.5 (3.8), 122 (4.8)
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]tire dia
[/TD]
[TD]=(B2+2*B3)/25.4
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]top
[/TD]
[TD]bottom
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]ring steps
[/TD]
[TD][/TD]
[TD]=LN(F8)/LN(D25)
[/TD]
[TD]=LN(G8)/LN(D25)
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]ratio of rings
[/TD]
[TD][/TD]
[TD]=E10/F10
[/TD]
[TD]=F10/G10
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]2-step ratio
[/TD]
[TD]1-step ratio
[/TD]
[TD]gear
[/TD]
[TD][/TD]
[TD]3rd
[/TD]
[TD]2nd
[/TD]
[TD]1st
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TD]
[TD]52
[/TD]
[TD]39
[/TD]
[TD]30
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]8x11 to 30
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]11
[/TD]
[TD]no gear
[/TD]
[TD]=IF(\$D12="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D12*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D12="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D12*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D12="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D12*G\$10*\$B\$4))
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]=IF(D12="no gear","",D14/D12)
[/TD]
[TD]=IF(D12="no gear","",D13/D12)
[/TD]
[TD]10
[/TD]
[TD]no gear
[/TD]
[TD]=IF(\$D13="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D13*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D13="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D13*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D13="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D13*G\$10*\$B\$4))
[/TD]
[TD]high
[/TD]
[TD]=MAX(E11:G22)
[/TD]
[/TR]
[TR]
[TD]=IF(D13="no gear","",D15/D13)
[/TD]
[TD]=IF(D13="no gear","",D14/D13)
[/TD]
[TD]9
[/TD]
[TD]no gear
[/TD]
[TD]=IF(\$D14="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D14*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D14="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D14*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D14="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D14*G\$10*\$B\$4))
[/TD]
[TD]low
[/TD]
[TD]=MIN(E11:G22)
[/TD]
[/TR]
[TR]
[TD]=IF(D14="no gear","",D16/D14)
[/TD]
[TD]=IF(D14="no gear","",D15/D14)
[/TD]
[TD]8
[/TD]
[TD]11
[/TD]
[TD]=IF(\$D15="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D15*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D15="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D15*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D15="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D15*G\$10*\$B\$4))
[/TD]
[TD]overall ratio
[/TD]
[TD]=I13/I14
[/TD]
[/TR]
[TR]
[TD]=IF(D15="no gear","",D17/D15)
[/TD]
[TD]=IF(D15="no gear","",D16/D15)
[/TD]
[TD]7
[/TD]
[TD]13
[/TD]
[TD]=IF(\$D16="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D16*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D16="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D16*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D16="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D16*G\$10*\$B\$4))
[/TD]
[TD]chain wrap
[/TD]
[TD]=MAX(E10:G10)-MIN(E10:G10)+MAX(D1222)-MIN(D1222)
[/TD]
[/TR]
[TR]
[TD]=IF(D16="no gear","",D18/D16)
[/TD]
[TD]=IF(D16="no gear","",D17/D16)
[/TD]
[TD]6
[/TD]
[TD]15
[/TD]
[TD]=IF(\$D17="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D17*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D17="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D17*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D17="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D17*G\$10*\$B\$4))
[/TD]
[TD]RD max cog
[/TD]
[TD]=MAX(D1222)
[/TD]
[/TR]
[TR]
[TD]=IF(D17="no gear","",D19/D17)
[/TD]
[TD]=IF(D17="no gear","",D18/D17)
[/TD]
[TD]5
[/TD]
[TD]17
[/TD]
[TD]=IF(\$D18="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D18*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D18="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D18*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D18="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D18*G\$10*\$B\$4))
[/TD]
[TD]FD diff
[/TD]
[TD]=MAX(E10:G10)-MIN(E10:G10)
[/TD]
[/TR]
[TR]
[TD]=IF(D18="no gear","",D20/D18)
[/TD]
[TD]=IF(D18="no gear","",D19/D18)
[/TD]
[TD]4
[/TD]
[TD]20
[/TD]
[TD]=IF(\$D19="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D19*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D19="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D19*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D19="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D19*G\$10*\$B\$4))
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]=IF(D19="no gear","",D21/D19)
[/TD]
[TD]=IF(D19="no gear","",D20/D19)
[/TD]
[TD]3
[/TD]
[TD]23
[/TD]
[TD]=IF(\$D20="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D20*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D20="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D20*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D20="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D20*G\$10*\$B\$4))
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]=IF(D20="no gear","",D22/D20)
[/TD]
[TD]=IF(D20="no gear","",D21/D20)
[/TD]
[TD]2
[/TD]
[TD]26
[/TD]
[TD]=IF(\$D21="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D21*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D21="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D21*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D21="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D21*G\$10*\$B\$4))
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD]=IF(D21="no gear","",D22/D21)
[/TD]
[TD]1
[/TD]
[TD]30
[/TD]
[TD]=IF(\$D22="no gear", "no gear",IF(E\$10="no gear", "no gear",1/\$D22*E\$10*\$B\$4))
[/TD]
[TD]=IF(\$D22="no gear", "no gear",IF(F\$10="no gear", "no gear",1/\$D22*F\$10*\$B\$4))
[/TD]
[TD]=IF(\$D22="no gear", "no gear",IF(G\$10="no gear", "no gear",1/\$D22*G\$10*\$B\$4))
[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]cog ratio
[/TD]
[TD]=D22/MIN(D1221)
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]# gears
[/TD]
[TD]=COUNT(B13:B22)+1
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]one step
[/TD]
[TD]=(MAX(D1222)/MIN(D1222))^(1/(D24-1))
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]half step
[/TD]
[TD]=SQRT(D25)
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]1.5 step
[/TD]
[TD]=D26^3
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]2 step
[/TD]
[TD]=D25^2
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]3 step
[/TD]
[TD]=D27^2
[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[/TABLE]

08-19-14, 10:19 AM   #7
ThermionicScott
Gratuitous glib and snark

Join Date: Aug 2011
Location: CID
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers)
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Hey @Darth Lefty, I've done a very similar thing, although using a different approach. You can't be too OCD when going down this path or the deviations from the "ideal" progression (done to limit manufacturing scope, I'm sure) will drive you nuts! For instance, once I had played around with this for a while, I wished that my 13-15-17-19-21-24-28 cassettes were 13-15-17-19-22-25-28.

What I did was to fire up an Excel spreadsheet with the starting cog and a certain percentage over 100% (ex: 1.1 for ~10% jumps) in the top two cells. Every following cog is the rounded version of prior one multiplied by that percentage. From there, you can tweak the percentage and copy cells until you have the cassette size and range you want.

(I'm not an Excel "power user" so it had to be simple. )
__________________
Quote:
 Originally Posted by chandltp There's no such thing as too far.. just lack of time
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Last edited by ThermionicScott; 08-19-14 at 10:25 AM.

 08-19-14, 10:27 AM #8 Bill Kapaun Senior Member     Join Date: Feb 2007 Location: Mid Willamette Valley, Orygun Bikes: 86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds. Posts: 10,023 Mentioned: 2 Post(s) Tagged: 0 Thread(s) Quoted: 369 Post(s) I've always plotted my gears on a spreadsheet. In the end, I swap in the cogs my legs & lungs like. In cold weather where I'm bundled up and my conditioning is at its minimum, I use lower gears than warm weather where I'm wearing shorts and my conditioning is better.
 08-19-14, 11:03 AM #9 Reynolds  Passista     Join Date: Jul 2005 Bikes: 1998 Pinarello Asolo, 1992 KHS Montaña pro, 1980 Raleigh DL-1, IGH Hybrid, IGH Utility Posts: 5,907 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 184 Post(s) My "rule" is trying to get about 10% jumps.
 08-19-14, 11:13 AM #10 Darth Lefty  Disco Infiltrator Thread Starter     Join Date: May 2013 Location: Orangevale CA Bikes: '76 Paramount, 02 Hardrock, '98 C'Dale XR800, '04 Burley Samba Posts: 7,484 Mentioned: 27 Post(s) Tagged: 0 Thread(s) Quoted: 738 Post(s) @ThermionicScott that works! It seems that once out of the corncob section most cassettes available go about 1.15:1, and this makes a good double shift with 52-39 or 42-32 rings. Some are more clever, especially with fewer gears. 5-speed touring freewheels (5x14-32) were about 1.23:1. The SRAM 7-speed 12-32 MTB cassette is 1.15 for the top four shifts and 1.23 for the bottom two.
 08-19-14, 02:33 PM #11 Dfrost  Senior Member     Join Date: May 2013 Location: Pacific Northwest Bikes: '87 Marinoni SLX (now 650B) Sport Touring, '79 Miyata 912, Wife's New IF Custom, Redline Posts: 820 Mentioned: 24 Post(s) Tagged: 0 Thread(s) Quoted: 80 Post(s) I find that bigger steps work fine on the ends of the cassette, but a single tooth step can be valuable in the middle, assuming that the middle of the cassette has the "flat road" gears. And I suspect that you will have a hard time finding 22t cogs.
 08-20-14, 08:13 PM #12 seedsbelize  Cyclist     Join Date: Nov 2010 Location: Tixkokob, Yucatán, México Bikes: '84 Schwinn Letour Luxe, 91 Giant Yukon, 92 Schwinn Paramount PDG 5 '72 World Voyageur Posts: 5,149 Mentioned: 30 Post(s) Tagged: 0 Thread(s) Quoted: 1427 Post(s) It's all Greek to me. __________________ I like pie.