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Does the future have fewer gears? - Further experiments - Part 1
51T cog removed
When you get quite deep into NSMB's Andrew Major's "Does the future have fewer gears?" rabbit hole, quite interesting things can happen.
https://nsmb.com/articles/does-future-have-fewer-gears/
https://nsmb.com/articles/axs-strikes-back-does-future-have-fewer-gears-pt-ii/
https://nsmb.com/articles/going-14-speed/
A couple of background facts
- MTB for me is all about winching myself up somehow on a moderate steep fireroad / singletrack, and then the downhill is going to be interesting.
- I do not care what is the maximum speed that I can achieve by pedalling downhill on gravel or fireroads. If we talk about MTB then it should mean a narrow singletracks, where pedalling with 40 km/h is quite impossible.
- I run a 28T front chainring on a 29er Nukeproof Reactor
- With all the responsibilities as growing older I am lucky if I can go out 1X a week, meaning puny fittness.
- I am not a weight weenie as I do not care if I reach the top of the hill about 25 seconds or a minute later, and I have a faint feeling that a heavier bike remains somewhat more stable on the descends. Although I am a strong beleiver in reducing the unsprung mass. (Ryan Palmer from BETA might argue with this regarding rear shock rebound tuneability.)
- I live in Hungary (Central Europe), where the elevation can be smaller smaller side, so a general 130 trail bike is usually enough for 95% of the time.
Soproni-hegység mountain biking trails
- MTB for me is all about winching myself up somehow on a moderate steep fireroad / singletrack, and then the downhill is going to be interesting.
- I do not care what is the maximum speed that I can achieve by pedalling downhill on gravel or fireroads. If we talk about MTB then it should mean a narrow singletracks, where pedalling with 40 km/h is quite impossible.
- I run a 28T front chainring on a 29er Nukeproof Reactor
- With all the responsibilities as growing older I am lucky if I can go out 1X a week, meaning puny fittness.
- I am not a weight weenie as I do not care if I reach the top of the hill about 25 seconds or a minute later, and I have a faint feeling that a heavier bike remains somewhat more stable on the descends. Although I am a strong beleiver in reducing the unsprung mass. (Ryan Palmer from BETA might argue with this regarding rear shock rebound tuneability.)
- I live in Hungary (Central Europe), where the elevation can be smaller smaller side, so a general 130 trail bike is usually enough for 95% of the time.
Soproni-hegység mountain biking trails
Modifying an 11 speed Deore casette to 10 speed
I was runnning a 11T-42T SLX M7000 11 speed casette that was working fairly okay, although there were a couple of ascents where I did not feel very good when I was tired. (I am not really looking for the steepest ascents, but where I can get to the top relatively easy and fast)
As my old casette is almost at the end of its carrier, I was looking around for 11 speed 11-46 range casettes (this would be a sweet spot for me with range, weight, compatibility, local terrain), but none of them were the one, for which I would say this is perfect. Either I had issues with the largest sprocket (alloy = fast wear, steel = heavy), or the gear ratios are a bit awkward after each other (regards to the Shimano guys with their M7000/M8000 11T-46T casettes and their 37T to 46T jump)
Although when the new Deore series was launched Shimano also introduced the M5100 series that has a 11T-51T range 11 speed spaced casette. The construction for this is quite okay from my perspective, but it is still heavy, and it has more range than I need.
On the other hand the biggest cog (51T) was riveted to the smaller one (39T). From this point I got my gears turning (pun intended). What if I just remove the largest cog by drilling the rivets? After all Shimano has a 10T-45T range, 12 speed casette (I guess not by mistake).
After buying a second hand casette (as I was not really sure this thing would be a success after all), I turned on my milling machine and drilled off the rivets that are connecting the two largest cogs.
Rivets all around waiting to be drilled off
Saturday night fever
51T cog removed
At the end I had a 10 speed casette with 11 speed spacing and 11T-45T range.
I had a bit of anxiety as the 51T cog reinforces the 45T with the rivets, and I will bend it like a banana with a good sprint under my 82 kg. Although during the first tests there was nothing that would resemble to this, even with the hardest sprints.
Winning
- With the rivets together 130 gram was coming off, so I am at about 490 gram instead of the original 622 (to be on the bling-bling side the lockring was replaced for an aluminum one for -7 gram). As a result I can not really find a similar casette with similar weight.
Key attributes
- around 11T-45T range
- all steel cogs with alloy spider
- mounts on a standard HG freehub
- I do not have to change my 11 speed Shimano (shifter and derailleur) setup
- as light as possible
Count carefully
Some data for comparison
Shimano Deore M5100 (original) | 11-51 | 11 speed spacing | 622 gram
Shimano Deore M5100 (modified) | 11-45 | 11 speed spacing | 490 gram
Sunrace CS-MX8 EAZ | 11-46 | 11 speed spacing | 485 gram
Sunrace CSMS8 EAZ | 11-46 | 11 speed spacing| 534 gram
Sram GX | 10-50 | 12 speed spacing | 450 gram
Shimano SLX M7100 | 10-45 | 12 speed spacing | 513 gram
Shimano XT M8100 | 10-45 | 12 speed spacing | 461 gram
Sunrace CSMS3 TAZ | 11-46 | 10 speed spacing | 486 gram
The Sunrace CSMS3 TAZ casette would be similar weightwise to the modified Deore, although I would have to change the chain, shifter, rear derailleur, and my chainline would be almost as bad in the easiest gear as it was originally with the M7000 casette on the largest cog.
- Better chainline in the easiest gear (yes, this would be also present if I leave the largest cog on, just never shifting to that one. Than that would work as a very heavy dork disc
)- The cogs that are coming after each other make sense (The jump between 39-45 is a bit more friendly at the M5100 than between 37-46 at the M7000)
- All Shimano system. Say anything you want but I am a big beleiver in the synergies of components from the same manufacturer
- No aluminium cog
Stay tuned for diving deeper into the rabbit hole in part 2.
Author Info:
Member since Mar 23, 2008
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(I am 82 kg)
Best option to get a used one for a couple of bucks, and get experimenting.