Cycling UK Forum

I noticed that few new mountain bikes come with a 3x (3 front chain ring) setup.

When I looked for a new front shifter/derailleur for my 3x9 setup, it was like hunting for gold dust. Is that just because of the worldwide Covid-related bike shortage? Or are 3x setups becoming extinct?

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I can understand the advantages of a 1x drivetrain -- a front derailleur is unnecessary, making for easier maintenance. But I don't understand the appeal of a 2x system. Isn't it "better" to have 3x9 (=27) gear ratios than, say, 2x10 (=20)? Aren't the jumps between gears smaller with a 3x9?

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I have a cross-country mountain bike, with a sturdy pannier rack, and it goes EVERYWHERE! I use it to commute, to pick up HEAVY shopping, on (tame) mountain bike trails, long rides through forests, for long-weekend breaks, up and down steep hills, etc. So... I need a pretty wide range of gear ratios to cope with the widely different terrains and weights that I'm carrying.

Does this make me a rare case of someone who actually would be better off sticking with 3x9? Are 2x and 1x drivetrains "the future" for good reasons? Or are they just an arbitrary fashion trend?

Thanks for reading

Why are triple set-ups disappearing? I really don’t know. For a bike that is likely to be ridden at a wide variety of speeds, laden, light, leisurely and enthusiastically the triple makes perfect sense.

I wasn't aware that 2x systems had become a big thing in the mountain bike world - I thought 1x was the new norm. The reason they developed 1x set-ups for mountain bikes was to minimise the size of the front chain ring to give better clearance when going over obstacles and drops. In order to make this usable, they developed clutches for the rear derailleurs to allow them to cope with a far wider range of cog sizes on the rear cassette. Once they'd got over this technical hurdle, then 1x became a much more practical proposition, so fashion and the cost-savings of mass-production meant it spread across most of the mountain bike market, even though I'd bet only a small minority of riders actually do the sort of riding where the extra clearance is necessary. The main advantage most riders get from them is (as you say) no front derailleur to maintain, plus more straightforward gear changing as there's no choice between combinations of front and rear cogs.

3x set-ups are still out there, and they're better for certain types of off-road application. I've got an older mountain bike with a 3x set-up and I can beast my mates up very steep technical climbs (in 1st gear) or fast non-technical sprints (in top gear.) I haven't had to buy a front derailleur mech, but I've had to buy new front chainsets and had no problem getting 3x set-ups from all the usual retailers and ebay etc. I've seen a lot of 2x crank sets, but I thought they were for road bikes (known as 'compact' set-ups?) 2x makes sense on a road bike where they can provide all the gear ratios a roadie needs and shave a few grammes off the overall weight.

It sounds pretty clear you don't need a 1x set up, given that you're not doing any psycho technical mountain biking, but only you can say whether 2x or 3x would suit you best. On my mountain bike, I use all 3 front chain rings at some point in an average ride. My other two bikes (a hybrid and a folding mountain bike) all have 3x set-ups, but I never use the smallest chain rings on either, so I'd have been better off with 2x set-ups.

You can still get triple shifters new but it's getting dropped down the spec 'ladder' although it's still pretty decent. All Shimano stuff has supply problems.You can probably also get good spec triple shifters second hand for a decent price I would have thought as they're not in vogue any more.

1x has one good advantage for 'proper' mountain biking and that is that a narrow wide chainring can be used. This means the chain is much less likely to come off over rough ground, although a clutch rear mech also really helps with that. No front mech is more simple too. Pretty much everything else is a disadvantage to my mind. Narrower range of gears even with huge and expensive dinner plate cassettes, with bigger jumps between the gears and a horrible rumbly 10 tooth sprocket. Any slight misalignment of the mech results in huge displacement on the larger sprockets. Bad chainline is unavoidable in some gears. 2x makes a bit more sense for mountainbiking to me, you do lose out on some of the higher gears but you still get a decent range without a stupid hi-hat cassette, it's simpler than a triple and you can run a bash guard to protect the rings. But for a do everything bike I would without a doubt stick with triple for as long as possible.

in theory 1x and 2x systems are lighter and they should also be cheaper (ha!). It is said that 1x systems are simpler to use....maybe... In practice such systems have other downsides vs setups with more chainrings.

So I don't think it is 'rare' to find a use where you would be better off sticking with a triple.

My view on all this is that there are several key factors which make 'progress' (if it an be called such) in this direction almost inevitable.

- more sprockets has been a trend, well, for ever really. It was said at least a decade ago that Shimano have patents up to 14 sprockets.

- if you have more sprockets you might need fewer chainrings. Or at least fewer chainrings might be a good excuse for more sprockets

- SRAM went off having more than one chainring and FDs in general the moment one of the Schleck brothers dropped their chain at a critical stage in the TdF.

- Shimano have slaved away trying to make indexed front shifting work and basically it is still a bit crap on most road bikes.

- FDs are likely to work less well whenever the chain is made narrower; you can scale everything down smaller but chainwheel flex is likely to increase not decrease.

If they want to sell us 1x13 or 2 x12 or whatever, then they have to come up with a good reason not to sell 3x9 or 3x10 instead.... well just because none of the manufacturers want to sell systems like that it doesn't mean that folk won't want them; an LBS near me has built several 3x11 systems...without indexed front shifting, of course.

cheers

A big reason for a single ring is that there is no need to work a front mech around an increasingly wide and complicated bottom bracket and swinging arm area. Also cheaper to miss out all the front shifting kit. It isn't lighter, this big steel sprockets weigh a lot as do clutch mechs which are also more fragile due to their length. Front mechs are the simplest and most fool proof moving part on a bike.
Doubles were a thing on MTB s for a few years. As with almost anything after the invention of pedals it's fashion which has always been dictated by the makers.
I suspect an element of a 1x system becoming acceptable is the ignorance of most new riders. Their experience is web based not years of apprentiship and they know no better and wouldn't know a decent pedalling style if it bit them. As MTB is the leader here, where nowadays pedalling isn't the done thing this isn't an issue. All subject to exceptions of course so don't tell me

Are the big sprockets steel? They are getting so huge at the back now (42T!) that aluminium would be quite strong and durable enough.

What is a "narrow-wide" chainring?What maintenance is needed on a front mech?Wash and spray lube after a dirty ride,otherwise very little.I get by with a double on my old spesh stumpjumper,in fact,an old campag mirage triple but only using the inner two rings.On my marin rift zone is an xt hollowtec triple with a steel middle ring,a pretty much faultless set up in the 13yrs I,ve owned it.Every ring gets used ,middle being the most used.Absolutely no reason to change.Aesthetically,IMO,a 1x11 looks awful,particularly the dinner plates sprockets.

Whilst I agree with the looks thing and find a 1x set up awful I think that those of us objecting may be using older kit or doing more traditional riding.
If all you do is uplift riding or trail park stuff then maybe a 1x works.
I still say much acceptance is ignorance though.
A mental check through club mates sees triples on the bikes of the old timers who are still using 26" wheels and do long cross county rides. The youngsters are different. Same on the road.
Is out that they have yet to learn or that they are less stuck in the mud?

cyclop wrote:What is a "narrow-wide" chainring?.....

it is an even-toothed chainring which has taller teeth than normal, which also more completely fill the spaces between the rollers in chain. Thus there are narrow plain teeth to go between the inner side plates and the other (wide) teeth also have scallops in them to allow enough space for the projecting ends of the inner side plates.

The idea is that the chain is less likely to unship vs a typical modern derailleur chainring, which has much shorter teeth, and has a generous lateral clearance so the chain will unship.

If you want a chainring that will run a singlespeed setup fairly reliably, you can dress the teeth on a 1/8" singlespeed chainring until a 3/32" chain is a snug fit. Not quite as good as a NW chainring but you won't be constrained by what is available from manufacturers.

cheers

...it could be fashion, but equally from a novice rider's point of view the triple chainset is a complication and may make the bicycle harder to use...

I've got a five speed, so the friction gear shifter goes up for a higher gear and down for a lower gear - its instinctive.

Compare that to a system which requires two gear shifters, one which can make a massive jump across the range and another for fine tuning and suddenly gear changes become a question of, push that one down and move that one up two or just move that one down four?
Having two sets of gearboxes does increase the range but it also means having to think to a deeper level to choose the right gear. Which depending on how your brain works may be something that you get straight away or may never get.

Then there's the mechanical servicing - a double chainset should work well as you can check that the outer plate follows the curve of the large chain ring and the inner plate follows the curve of the small chain ring, but it also means that when the chain is on the middle chainring there's nothing following the curve which may make any change less than precise.
Certainly from my point of view there was also the indexing of the front deraileur, depending on which rear sprocket the chain was on altered the angle of the chain and in some gear combinations would either mean a slight over shoot or a non change.
Possibly the best bike I never had for front deraileur indexing was my brother's peer gynt- a chain so long that its angle didn't change at all.

That's not to say I'm against them, but for ease of servicing I'd always run my triple (and once a quartet) with a friction shifter. And I may return to either a double or triple when my health weakens.

However if you're trying to sell new bikes to new people many of which have now been brought up with 'user friendly function technology' - it could been that much like friction shifters a triple is now too much for the new rider to be bothered with.

Us recumbent pilots have a similar need for a wide spread of ratios. I find Sugino, Sunrace, still make decent triples, and you can always buy a set of bare cranks, and suitable bolts and spacers to build up your own using rings from TA or others. (Although this is a route I have not personally tried yet.)

As for mechs, a front mech doesn’t get nearly the same use as a rear, so good quality second hand ones are not too hard to find. When wrestling with the set up, don’t forget the importance of B.B. axle width, and remember that a B.B. spacer ring can work magic - the aim being to get the chainweels positioned centrally within the range of movement of the shifter mechs cage.

3x is by no means extinct. Few things in cycling ever are!

cycle tramp wrote:...it could be fashion, but equally from a novice rider's point of view the triple chainset is a complication and may make the bicycle harder to use....

three rings, one each for uphill, flat and downhill-ish conditions.... is that really so complicated?

The gear ranges always overlap so you don't have to shift at one specific point, you just let your legs tell you what gear you need....

cheers

It's not complicated at all but sadly nowadays we always seem to cater for the lowest possible standards of intelligence. Now we say"poor thing, let's make it easier so you don't need to think too much" instead of " damn well get on with it and learn"
Cynical, me?

Brucey wrote:

cycle tramp wrote:...it could be fashion, but equally from a novice rider's point of view the triple chainset is a complication and may make the bicycle harder to use....

three rings, one each for uphill, flat and downhill-ish conditions.... is that really so complicated?

The gear ranges always overlap so you don't have to shift at one specific point, you just let your legs tell you what gear you need....

cheers

Exactly what I have done with my bikes. Very nearly perfect for how I use them. The only fly in the ointment is the difficulty (actually, prohibitive cost) of customising cassette ratios. Most cassettes present a minimum tooth difference count too far down the block to be of maximum use. If I had a 10 speed cassette with 12-14-16-17-18-19-20-22-25-28 I would get off the middle ring more often and each cog less, prolonging their lifespan.