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bobknh

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Reply with quote  #1 
I saw an announcement from Shimano for their long anticipated 12 speed mountain bike system. 10-51 12 speed cassette, clutch der. etc. Hidden further down in the announcement was a statement that Shimano will stop making triple mountain bike cranksets. There is a long thread here discussing the relative merits of 1x, and 2x --- but what about 3x? In all of the buzz about exotic 12 speed cassettes an 1x der's, it seems that the industry has more or less abandoned high end 3x cranksets. IMHO, that's a shame. 3x would solve a lot of gearing demands for gravel cycling because on the one hand, it allows you to use fairly close spacing on cassette cogs, while at the same time offering an expanded gear range required for the multi surface and hilly terrain we ride. Of course, you will be able to get older model triples with up to 10 speed cassettes; and expensive triple's from small manufacturers like White Industries, but forget about hydraulic brake shifters and electronic shifting. Maybe I'm being too retro in my thinking, but is this is another case of style and marketing hype, replacing good engineering?
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bobknh

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Reply with quote  #2 
Here is Gerard Vrooman's  take on 1x, 2x, 3x --- http://www.velonews.com/2018/06/from-the-mag/qa-gerard-vroomen-on-the-future-of-bike-technology_468019
From his POV -- not only is 3x ancient history - but someday we'll all be riding 1x. AAAAAAGH!
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dangle

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Reply with quote  #3 
This has already been discussed to death. If people bought them or there were actual advantages, they would still be sold/promoted. 2x isn't going to disappear, but 3x is gone and never coming back. 1x and 2x have their places for certain applications.

I'm curious how any current 3x system has a better usable range than current 2x. How would 3x "solve gearing demands for gravel cycling" by "fairly close spacing on cassette cogs" and "an expanded gear range" is what I'm itching to know. Range and gaps are constantly tossed out as reasons, but I haven't seen any numbers to back it up. Do you have them?

What incredible times we live in that one can buy a 46/30 and pair it with an 11-32 rear within just about any road bike drivetrain for a range that has got to cover 90% of the population with 15-16 distinctly different gears (depending on when you cross between the big rings). If we're still talking gravel, how does anybody need anything bigger than a 46? The last few 1x rigs I remember seeing on the Dirty Kanza podium maxed out at a 44 tooth ring and those guys and girls get paid to ride bikes. Maybe you could squeeze out more 'range' with a 3x, but it will only be if you're geared way too high. Getting much below 30 gear inches on a normal 3x or 2x isn't terribly easy, but that's pretty low. Anything below 27 gear inches seems reserved for some pretty packed down bikes....or walking.

If 30f/32r is too low of a gear, one could use the SRAM 11-28 cassette. It is a corncob for the first 7 gears (11,12,13,14,15,16,17) so nobody can argue 'gaps' in there. The gap haters can click down to the 30 ring and start back at the 12 cog for 10 more distinctly different gears that are spaced closer together (percentage-wise). The 'gap' argument doesn't have much mathematical evidence if you're discussing modern drivetrains and 2x vs 3x.
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Skldmark

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Reply with quote  #4 
@Dangle— the place I feel a gap is when that 46t up front is too much and the 30t up front is too little. Facts and figures and statistics to come.
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clarksonxc

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Reply with quote  #5 
I'm a big fan of 2x for gravel, never really rode 3x enough to have a decent opinion.
That said, from the Shimano news link I read, 3x was just being phased out of the XTR line for now.  I'd like to believe that XT or Deore might still offer a triple for a while longer at least.
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Osco

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Reply with quote  #6 
3X has only 14 different gear ratio's out of 27 I think It was.
Long Cage derailleur, all that extra chain to control, the added parts and the third chainring.
I don't want all that junk on my bike.
Only place I see 3x's is on walmart bikes and old cheap bikes and a few very old classics.

But I do have a 3x on my Easy Racer Tour easy with It's three chains. On that LWB Recumbent 3x makes good sense IMHO. It's gear Inch range Is something like 23-127",, I cannot sustain the top three gears on the flats.

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Volsung

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Reply with quote  #7 
They're awesome for cargo bikes but triple FDs shift terribly.  The fewer chainrings you have the fewer shifting problems you have unless you go Di2, which I'm not doing on my Big Dummy.
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NoCoGreg

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Reply with quote  #8 
I'm with Dangle on this one...  Lemme go geek for a while:

With a 46/30 the big ring is 53% larger than the small.  Once upon a time when triples were all the rage, they typically were setup with:
Road:  52/42/32 =>  Big ring is 62.5% larger than the smallest
Mtn:  46/36/26 => Big ring is 77% larger than the small

But this was in a time when cassettes and freewheels only had 6 or 7 cogs which by today's standards were quite closely spaced.  A 14/34 was very wide range and not very common. 

46/14 = 3.29 big gear (which really isn't very big but I digress)
26/34 = 0.76 low gear

The total range (difference between the largest and smallest gear) is:
3.29/0.76 = 4.33

So if one has a 11 speed or 12 speed cassette with a 10t small cog and a 44t you now have the same range as the triples of long ago - and this is accomplished with the simplicity of a 1x setup.  The only question is whether or not the jumps between the gears are too large.

If one wanted to hit the same range as that 3x7 setup using a 2x setup:
46/3.29 = 14 tooth small cog
30/0.76 = 40 tooth large chainring

Or what IMHO is a more usable setup for gravel (46/30 with 11/34)
46/11 = 4.18
30/34 = 0.88

Total range is 4.18/0.88 = 4.75

Disclaimer on my geek analysis...  Yes there are all sorts of differences if one goes to the microdrive double and triple cranksets.  With smaller rings a 16-tooth gap becomes a higher percentage change - this is also why the 10t cassette cog helps with wide gear ratios (2t from 10t to 12t is 20%, the same as 8t in going from 40t to 48t).

IMO the basic criteria for selecting gearing:
1. What is the lowest gear needed?
2. What is the largest gear needed?
3. Can I achieve both of those and have jumps (gaps) between gears which are not too big?

IMO, a 2x11 setup can almost always achieve these 3 criteria. There might be extreme cases where a 3x setup could work better "on paper", but this would likely also require a custom setup of chainrings to achieve ultra wide gearing.

I still own several bikes with triples and they work fine, but I cannot see a NEED for a triple on a bike which has 11 or 12 gears in the back.

For mountain biking, where I prefer larger jumps between gears, my next bike will be a 1x12.

For road and gravel I do not foresee moving from a 2x setup as I often hang with racers so I need big gears for the flats yet some low gears for climbing.

Cheers,
Greg
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OffB10Path

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Reply with quote  #9 
Greg has more good thoughts here.  I too have both 2x and 3x setups, but I don't foresee going to 1x because my OCD won't let me cross-chain!  The straighter chain lines that triples afford are one of the reasons I like them.  Probably does more to satisfy my "feeling" of being more efficient than any actual reduction in watts lost to chain deflection, but I like it nonetheless.  One other thing I like about triples is the transition between rings.  16T drop has always felt clumsy to me. 

Totally agree that 3x and 11-12 cogs is complete overkill (on 2x road setups, as well), though.  With the larger big ring triples offer, I run 8 and 9 cogs from a 10 speed cassette, and keep the small cog to a 12T. 

The new 1x stuff looks awfully nice, but so pricey.  Maybe I'll get there one day, but for now don't see any real benefit that justifies the investment.  I like keeping my bikes on one standard, too, and for now that's 10 speed.  I'll probably run Ultegra and XT 10 speed stuff until you can't find it anymore.  Maybe not stylish, but it's so good and so cheap relative to the latest generation goodies. 
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