DaveSSS 

Yes done, but with big jumps between each sprocket. Not good for road or gravel.

Gear inches is a meaningless number, but for road bikes, it's usually just the gear ratio times 27. I never use it anymore. Only a 42 large sprocket is needed.

mirfi

Well, I'm mostly concerned with my 20inch(406) mini-velo/folders. So, I'd do that with a 58t chainwheel. Thank you.

BTW, I like that gear calculator, been using Sheldon Brown's for years.

noodle soup

Cool story Bro .

For road use(no mud), the chain drop issue has been figured out. 1x is still stupid for road though.

Dean V

How can you say it is stupid for road? It may be for some applications but certainly not all.
On the rolling terrain I ride with no huge climbs my 46 F and 11-32 R suits me fine.
The gear spacing is close enough for me.
The gear range is enough.
Overall there is less cross chaining as at cruising speeds around 20mph I am right in the middle of the cassette.
With a double I am often in the small front crossing to the smaller end of the cassette or vice versa on the large chain ring.

Maelochs

Yes, part of that "cool story" addressed that.

What I have been thinking about is this bit: I can see this---with electronic shifting programmed to auto-shift so the rider doesn't have to guess ratios ... super-quick shifts, lower Q factors because of the slimmer 12-speed chains and rings, a corn-cob cassettes and tremendous efficiency.

Sure, three rings are heavy ... but a 42- or 50-tooth cog is Enormously heavy.

DaveSSS 

The SRAM 10-52 cassette only weighs 300 grams, since the 52 is aluminum and there are many weight reducing cutouts. The problem with this is the very large jumps. I have a 48/32 crank with a SRAM 10-36 12 speed cassette that weighs the same and gives me a greater 540% range with much better sprocket spacing.

All 12 speed cassettes are pricey, but $185 for the 10-36 is a lot better than $450 for the 10-52. That's a lot of money for a wear item.

One problem with sequential electronic shifting is not knowing when a chainring shift might be made. That can lead to chain drops, if pedaling force is too high at the time of the shift. I don't use it.

Psimet2001 

This is what's going to drive the marketing. I would say it would be a way more efficient setup for racing but honestly a large 2x system with tight cassette already are. We aren't going to get faster on bikes so we have a good handle on the top end. So far it's been a race to the bottom (end of gearing).

Like with all trends "If 32 is big then let's try 34!"....36...42...48..50....52 guys these are chainring sizes. The roads haven't changed. We aren't getting faster. We were already spinning up climbs with triples and even compacts. We are to the point where 12 speed mtb groups are starting to hit obstacles when the gap isn't set right because they're hanging down too far. It's gone beyond ridiculous. We will go back it's just a matter of who does it and when.

Psimet2001 

Light - tight cassettes are less money and are about 100g lighter or 1/3 the weight. More than enough to throw on another ring up front. The weight savings is really in the front derailleur. Can't even say shifter anymore as electronic has made the weight of the buttons fairly minimal.

The crazy part about front shifting under load is that you can easily do it with electronic. If you're riding electronic now just go try it on your next ride. Ease into it until you feel comfortable but front shifting under load is where electronic shines. If you're dropping your chain at all that's arguably your setup or the chain itself. With all the crap we have been making chains do lately they wear out long before the actual roller wear becomes an issue. Lateral play gets to be so high that i have seen chains that aren't worn out normally do some funky stuff.

Had a Di2 DA setup the other day that had been perfect since I set it up a year or two ago. Chains were swapped, etc. Then her husband got involved. She came in one day complaining the drivetrain was super loud now. I look and her husband installed a directional Shimano chain the opposite direction. I flipped it around but the damage was done. He started buying chains online to save money (I sell mine for whatever the going online rate is usually anyway but people never want to believe that). She came back with a new KMC SL chain. I installed it. she rode a few hundred miles on it. She came back because it was super load again and it was dropping occasionally on the front when shifted from large to small. "Only way that happens is if someone touched it and moved my setup."

After checking with the one mechanic that is closer to her that she sometimes takes he bike to she swore no one had ever moved it. I was about the throw in the towel but I kept playing with it. Noticed the chain made the front shift fine but she had semi-synchro so it also dropped two cogs on the back after the front shift was complete. In dropping those two cogs I saw this sort of waveform show up in the chain. That little wave was throwing the chain off the front.

Grabbed the chain and I can flex it sideways back and forth a ton. Chain "sounds" like a worn out chain on a drivetrain. "This was a new chain, right? Did he buy some sort of factory second or something?" "Who knows Rob. He's always trying to save a buck."

I grabbed a new Shimano chain, put it on. Sound went away completely (silent drivetrain now) and front shifting issue went away completely. Grabbed the KMC and held it out and it flexed sideways into almost a full circle if I could have held it straight.

So...if the front comes off under load under electronic then it's position or the chain

noodle soup

On a mountain bike 1x and a huge 10-51t cassette works great because you don't really need a tight spaced cassette, but that same cassette would be horrible on the road.

what do you mean by "12 speed mtb groups are starting to hit obstacles when the gap isn't set right" ?

Psimet2001 

I was thinking about something I heard about (didn't see) but now that I think about it they were running 26" and/or 27.5". Between the smaller wheels and the cassette choice - blamo. By gap I meant gap to the ground

Regardless the derailleurs are starting to become monster truck style ridiculous and there's only so much chain you can wrap.

noodle soup

I could definitely see it being an issue with a 26er, but I can't recall the last 26er I've seen(other than BSOs)

79pmooney

Is it time for a SunTour 3-pulley derailleur again?

Psimet2001 

Had someone about a month back inquire about new wheels to keep his Ti 26" setup going. Wanted tubeless and wanted to use I9 hubs.

Tubeless, I9, Rim brake - 26". let that stew for a minute.

There are riders with nice rigs that refuse to let them go.

Psimet2001 

noodle soup

No carbon hoops?

Psimet2001 

I didn't look. He wanted alloy.

noodle soup

I can't even think of a 26" CF rim brake hoop.

GlennR

BTW... 650b are around.

Psimet2001 

27.5 for sure are available but 26.... There used to be a lot but last time I looked I could hardly find anything. Last month I had to buy up the remaining inventory (at retail) for a particular rim that finally went out of production and isn't coming back in 26. I have a benefactor that wants to use that rim specifically so - gotta keep it in house.

Seattle Forrest

Has anybody contemplated 0x?

DrIsotope

Bro, that's already a thing. They even race 'em.

Sy Reene

Of course. Been around for ages.. but only those recumbent riders seem to like them

noodle soup

0x isn't just for recumbents.



0x with an IG hub.