Custom 9 speed 12-32 cassette?

[PeterBL]

Have you considered using BBB cassettes. You can build a 12-14-16-18-20-22-24-28-32 from a 12/13/14/15/16/18/20/22/25 and a 11/12/14/16/18/20/24/28/32. See
https://bbbcycling.com/en/bike-parts/cassettes/BCS-09S

Not the cheapest solution but at least you get your ideal cassette. There is usually a good selection available on ebay.

I haven't seen these before. The gaps on their 12-25 are very nice!

[Manc33]

I was also messing about with 12-26t cassettes in 9-speed trying to add in a 16t etc and could never get it working. Either the shift was bad because of spacing, or the teeth didn't align right. Gave up in the end.

Shimano make only one 11-32t cassette in 9 speed that I know of, that doesn't have a nasty jump - the very cheapo Acera/Altus level "CS-HG200-9".

That cassette goes like this:

11-13-15-17-19-21-24-28-32

The more expensive 9-speed HG50's in 11-32t all start with "11-12-14" like old XT/XTR and put a 18-21 gap in (or on 11-34t, a 17-20 gap) as highlighted by the OP. (11-12-14-16-18-21-24-28-32 / 11-13-15-17-20-23-26-30-34)

I found the only sane option to avoid all of this while keeping a reasonably big low sprocket was a 12-27t (12-13-14-15-17-19-21-24-27). I wanted a lower gear.

You can't do anything above 12-27t, even with the 11-28t that ruddy gap comes back again! (11-12-13-14-16-18-21-24-28).

Why do that if they could do 11-12-13-15-17-19-21-24-28.

Its always perplexing. I have even seen guys saying they are going back to 6-speed (MTB). You seemed to be able to make any cassette you wanted back then, up to about 30t on the old Uniglide 600 stuff. Yes this causes big gaps everywhere but the drivetrain lasts ages, sprockets can be flipped, shifts are better, less gears to think about, cleaning is easier... get the thumb shifters back out.

Shifts definitely went worse 8-speed to 9-speed. The only reason I went from 8 to 9 was because I could't have a 12-32t without a big gap, but hey at least 8-speed has a 12-32t, they are non-existent in 9-speed, it seems.

With 36t and 48t chainrings, no one needs an 11t. With a 44t outer or 42t thats pushing it and a 12t gets annoying downhill.

[Brucey]

if you are really keen to get a mixed bag of HG cogs shifting sweetly, you can sometimes do it by

a) choosing your mixed bag of cogs very carefully and

b) modifying the timing spline on the HG fitment so that some of the sprockets can be refitted on a different spline, in order to improve the ramp alignment.

If I had to characterise the development of indexed shifting in simple terms, each new generation of shifting gets less clunky (i.e. smoother under load) and less long-lived between various bits wearing out or going out of adjustment. All the way from 6s uniglide to 11s HG this applies, more or less.

On road and touring bikes I would still happily use UG (and do) but on MTBs you more often need to make a shift under duress (i.e. load) and HG is better for this.

cheers

[BigG]

its OK but (if it is the standard shimano 11-32 cassette) there are ~17% gaps in there between 12-14 and 18-21 that (pretty much) persist in the final gearing. There is no gear between 52" and 61". 26-34-42 and 12-32 cassette (say) gives the same range with much smaller gaps, easier double-shifts etc

http://www.gear-calculator.com/?GR=DERS&KB=26,34,42&RZ=12,14,16,18,20,22,24,28,32&UF=2240&TF=90&SL=2.6&UN=MPH&GR2=DERS&KB2=26,39&RZ2=11,12,14,16,18,21,24,28,32&UF2=2240

cheers

I'd love a 9 speed 12-14-16-18-20-22-24-28-32

What's the best way to achieve that?

Those 17-20 and 18-21 jumps on standard cassettes make me mad

Currently use (very happily) custom 8 speed 13-15-17-19-21-24-28-32 cassettes on most bikes, but would like the 9 speed 12-32 on the Moulton TSR

12/14 and 24/28 in your "ideal" cassette give exactly the same gear gaps (18/21) that you dislike in standard set-ups.

[landsurfer]

I ride 12 - 32 cassettes on all my bikes ... usually with a 36 or 34 front ring.
I regard the ratios as almost "variable" in their nature.
I never think , Hill ahead , i must change to a 21 tooth sprocket , rather i feel the torque required to ascend at a comfortable rate.
The idea that i should have a set ratio for each aspect of my riding is ... weird .. to be honest.

[Manc33]

There are a lot of variables. Filing new splines isn't a length I would go to but I can understand why some would with a lot of riding.

I get sick of the jumps and try 11-X, 12-X, 13-X then those low would be 25, 26, 27, 28 lol tried them all.

I can't even run a 27t properly because of my fat chainstay being where the rear mech needs to be on the smallest sprocket. With a 32t/34t lowest on, its OK because the b-tension is opened out enough that it doesn't overlap on the highest gears. This was usable but I got delays shifting on the outer and highest gears, plus I got sick of using the granny way more when I always managed to avoid it, so I went back to a 32t low again.

The only rational choice if you want Shimano and don't want to mix sprockets, on 9-speed, is that cheap Altus with 11-13-15-17-19-21-24-28-32t. I think its marketed as some sort of touring cassette rather than MTB, but its so cheap, I am sure it doesn't shift like the HG41/HG50 do. Come on Shimano make a HG50 with these sprockets!

In fact 12-32t would be better as per the topic, there isn't a Shimano variant. 12-13-15-17-19-21-24-28-32

Those ratios are probably enough to make the 11-speed folks jealous £££££

That might even answer why Shimano isn't making those 9-speed choices (conspiracy theory sorry).

[Brucey]

....12/14 and 24/28 in your "ideal" cassette give exactly the same gear gaps (18/21) that you dislike in standard set-ups.

yes, but they don't give gaps in the middle of the gear range. IME if you are going to have larger gaps between some ratios than others (and with a derailleur setup this is almost inevitable), better that they are between climbing ratios, or ratios that you might use downhill with a tailwind, than ratios that you might want to use on near-flat roads.

The reasons for this are to do with the way in which the required power output is likely to vary with gradient etc at various speeds, and what proportion of your effort is dissipated against air resistance.

cheers

[Brucey]

.... Filing new splines isn't a length I would go to.....

you only need remove part of the timing spline to greatly expand your options

cheers

[deliquium]

....12/14 and 24/28 in your "ideal" cassette give exactly the same gear gaps (18/21) that you dislike in standard set-ups.

yes, but they don't give gaps in the middle of the gear range. IME if you are going to have larger gaps between some ratios than others (and with a derailleur setup this is almost inevitable), better that they are between climbing ratios, or ratios that you might use downhill with a tailwind, than ratios that you might want to use on near-flat roads.

The reasons for this are to do with the way in which the required power output is likely to vary with gradient etc at various speeds, and what proportion of your effort is dissipated against air resistance.

cheers

^ That's exactly my take/preference too

The 12 sprocket is only an 'overdrive' for me, hardly gets used as I really don't see the point in pedaling into a brick wall of air at 20mph (unless I was paid to). Not to mention plus twos and Nelson Longflaps aren't very 'aero'

[Scunnered]

I'd love a 9 speed 12-14-16-18-20-22-24-28-32

What's the best way to achieve that?

Those 17-20 and 18-21 jumps on standard cassettes make me mad

Currently use (very happily) custom 8 speed 13-15-17-19-21-24-28-32 cassettes on most bikes, but would like the 9 speed 12-32 on the Moulton TSR

I intend to make something like this by splitting up a 10-speed 11-32 together with various 9-speed sprockets:

14-15 (or 13-14) from 9-speed
16-18-20-22-25 from 10-speed
28-32 from 9-speed

To get the spacing right, I will use a mix of 8 and 9-speed spacers.

[NetworkMan]

I'm in the same position as I'm starting to dislike the 18-21 jump on my 11-32 and the 11T always was too small. Has anyone made a 12-32 or 13-32 recently?

Thanks Manc33 for pointing out the the HG200 11-32 9 speed is different! That was a revelation since I'd assumed that all Shimano xx-yy 9 speeds would have the same intermediate ratios. Are there any other oddities like this? If so should we point them out in a separate too-good-to-lose (moderator?). It seems that there is now an HG-201 with the same ratios which is plated. One of these 11-32s should suit me much better I think.

Has any one tried putting a 32 on the back of a 12-27 9 speed and replacing the 12 and 13 with a 13 top cog to get 13-32? There may be an issue with the top cogs being recessed. Also the 12-27 HG50 seems to be obsolete and only the ULtegra with spider is left.

[Gattonero]

I'm obviously not the only one on this forum who takes issue with this plainly BAD thing?

but how much of an issue?
There are a few times when conditions are favourable enough for this to bother me but not enough to make me consider paying another £10 per cassette.

Same here, not that fussy at all!

[reohn2]

I'm obviously not the only one on this forum who takes issue with this plainly BAD thing?

but how much of an issue?
There are a few times when conditions are favourable enough for this to bother me but not enough to make me consider paying another £10 per cassette.

Same here, not that fussy at all!

The thread is for those who are a bit fussy though.
Personally I like the progresssion in the middle and higher gears to be two teeth apart,anymore and my legs don't appreciate the jump at the lower end I just glad I can find a ratio I can pedal.
Currently after many years of a 14,17,19,21,23,25,28,32 8speed cassette made from 14-25 Tiagra and an 11-32 hg 500 9sp cassette,
Because of the 14 to 17 chasm,I bought a pair of DA 9sp levers and made up a 14,15,17,19,21,23,25,28,32 but the change from 15 to 17 wasn't as slick as I liked,so after taking the back off the index spline with a Dremel to get the cog as close to the ramped position as possible,and the bike hung up in the stand,observing closely where the problem lay,I doctored the tooth profile of two teeth on the 17t cog to help the chain climb up,it's now much better.
NOTE,if using STI's either road or MTB this problem doesn't exist as changing to bigger sprockets are more easily slightly over shifted,so much so that STI users do it all the time without realising it.

[Mick F]

I often try to get my rudimentary grasp of arithmetic to cope with trying to design a cassette with the same percentage gaps between all the sprockets. Obviously, it can't be exact and completely smooth, but it must be possible to get some way towards it.

[reohn2]

I often try to get my rudimentary grasp of arithmetic to cope with trying to design a cassette with the same percentage gaps between all the sprockets. Obviously, it can't be exact and completely smooth, but it must be possible to get some way towards it.

That about sums it up,if the favourable changes suit the individual then they're happy and their cycling is more pleasurable as a result.