deckas 1x red chainring shimano alivio

Pros and cons of 1x drivetrains

We all love the idea of a simplified bike. One of the promises of 1x drivetrains was “simplification”.

Have you ever seen anything simplified in the last decade, regarding bikes?

First, we had 130mm rear hubs for road, 135mm rear hubs for MTB’s. We have QR (quick release) working well for almost a half century, made first by Campagnolo.

Now we have a “Boost” standard, and almost nobody can explain. 135×10, 142×12, 150×12, 157×12 and 165×12. Now we have 148x12mm Boost hubs. Which thru axle to get? That’s so complicated!

Or, we have hydraulic brakes now. You can’t be sure if your new caliper will fit your disc. No universal pad area size…

For tires, we have 26 inch for a long time. Then 27.5 is the king for a short period, lost it to 29, now 27.5 getting a bit of love again.

Bike and bike part manufacturers keep changing the standards, because in the old days, bike is a thing we use for quite a long time. This is not profitable.

1x chainring
Chinese companies like Deckas, and various Chinese crankset makers made 1x a viable option for everyone. For the price of a bottom bracket for big boys, you can get a whole set. Some of these Chinese products are really superb.

Back again to 1x…

1x gained traction by the push of Sram, which is not famous for building elegant and refined front derailleurs and chainrings, and bike industry media. It seems to address some long standing issues: 2x or 3x drivetrains are complex for users, heavy, needs more service and since we have so many overlapping gears, its just not needed anymore…because someone just thought of ditching other chainrings, leaving a single one instead. This is what I call genious.

Let’s not forget; now we have very clean cockpit thanks to left shifter dropped; and lets put a shock lock, seat post trigger there. Nice.

Why 1x is a bad idea?

When people were riding awesomely complex 2x – 3x bikes, they got so puzzled that they never learned how to shift, causing cross chain issues. Let me simply tell what cross-chaining is, because it’s a problem long gone by now, nobody ever knew it.

Let’s say you have an archaic 11-25 cassette and 54-39 immensely super complex crankset. If you have a 9 speed cassette, and a 2 chainring crankset, its ideal to “partition” cassette cog – chainring combos, like switching to 50 chainring when using 11-13-15 cogs of the cassette, or using 25-23-21 tooth cogs of the cassette when on 30T chainring. That way, chain stays relatively straight across chainring and cog.

Cross chaining is bad in many ways. It adds to friction, makes drivetrain noisier, wears components faster. It’s not just cross chaining that shortens chain life: to eliminate chain drops, 1x rear derailleurs applies more tension to chain, causing increased friction and wear.

Bike industry media also invented a new metric to accompany this genious invention; and its called “range”, in %. What do they mean? In laymen terms, if you have 200% range, it means you are travelling 2x faster then the slowest gear in the highest gear, if you are pedalling at same pace, or cadence.

“Gearing ranges over 450%, up to 5xx!” advertised as rocket science. Funny thing is, 48-34-20 crankset with a 10 cog 11-32 cassette does have 700% range. It’s one of the most basic setup in the book; preferred by tourers.

Well, I have the latest, kick-ass invention of all time: 1×2. Yes, no more anxiety, thinking “which gear I’m in?” – your legs will immediately know! Super simple cockpit; just one shifter with single lever: push for first gear, and pull for second gear. And it has immense “range”: 10-100 cassette is not just lightweight, it also have %1000 range! Your spokes are also protected, thanks to “shield my rim” cassette technology, that covers almost all your rim.

In an ideal world, we’d like to have CVT transmissions on our bikes, because its ideal to pedal at certain rpm, or in bike-speak, cadence. However, we have limited number of cogs. These cogs and chainring sizes remained quite close, if not strict, for decades. It’s easy to see why, because we humans have not evolved in a few decades. These are the ratios that are fit for humans, tried and tested in time.

Gearing range is important, but spacing is more important in most cases. 1x drivetrains, which is 13 speed tops, provides a good range, but poor spacing. What spacing means? It helps you maintain your cadence. Gear ratios are closer, so you are not either spinning like a crazy monkey, or a tired bear. This is why you won’t see 1x drivetrains in road racing; instead, you see nicely spread gears and 2x cranksets.

1x advocates tricks people using numbers people cannot comprehend; like gear ratios. Let me give you an example: With 52t chainring, gear ratios of 11t and 12t cassette cogs is 4.73 and 4.33 respectively. Seems like a small number, right? With 90 RPM cadence, you will reach 33.5 km/h when on 11t cog, and 30.7 on 12t cog. An experienced road biker knows the difference, especially at this speed, nothing something minor! It’s a great difference. It’s not just about speed: you need to put out extra 30-40 watts or more to maintain that %10 speed difference. So, small numbers matter in gear ratios.

One other thing is, while blaming 2x or 3x cranksets, saying people always use wrong combos, thus causing cross chaining, is absolute bullshit. Yes; most people don’t know how to use gears. These are the people that buys bikes from supermarkets, and leave them to rot after 1-2 rides. People spending 2000$+ dollars to MTB’s with 1×11 drivetrains knows a thing or two about gears. 1x bikes have pitiful chainlines, which creates cross chaining, and there is no way to get over it. Funnily, MTB’s have shortened chainstays, especially coinciding the release of 1x groupsets, so cross chaining is a much bigger issue for MTB’s rather then real touring bike frames, when it comes to cross-chaining.

Maybe I’m being too harsh on 1x – because Sram is too aggressively promoting it, which created a bandwagon effect. Even Campagnolo, which is known to be a “conservative” company, released Ekar groupset for gravel. 1×13. Sram tries to convince people 1x is also good for road bikes.

1x is good for many bikes, like fat bikes, folding bikes, downhill or kids bikes. But not for touring bikes, road bikes, or gravel bikes.

When to go 1x?

At least for me, I want to get most out of my legs when going long, or fast. When driving a folding bike, or a fat bike, I don’t care. In fact, these are “leisure activities” and I like the simplicity of 1x. Efficiency doesn’t count. Not just efficiency: I wouldn’t want an another front derailleur to adjust, or extra cable to replace on such bikes. I wouldn’t care if components wear faster, as I won’t be touring the world with a fat bike, or a folding bike.

It’s much like driving a small hybrid to work, driving a ’68 Mustang in the weekend. You won’t be thinking about MPG in a weekend toy.

For downhill bikes, or any bike you barely need to pedal, anything more then 1x is an overkill, and stupid.

For me, greatest benefits of 1x drivetrains is simplicity (one lever to operate) and maintenance.

The weight advantage is not so abysmal; you can shave off 300-500 grams of depending on your setup.

Funnily, off-the-box 1x drivetrains are generally more expensive than 2x or 3x setups, due to clutch rear derailleurs and huge cassettes.

Ghetto 1x

I ran a 1×9 setup on a 26′ wheel “city bike” for quite long. 11-28 cassette and 38t chainring. I was quite happy with this setup, as the city I use this bike was almost flat.

This setup almost cost me nothing: I have a spare, trusty Shimano Deore XT 760 crankset lying around, with equally perfect Deore XT 771 rear derailleur. Just removed the 3 chainrings, installed a 38t Deckas 1x chainring from AliExpress, along with a Altus 9s shifter.

This setup needed no chain retainer, and you may already know, there is no clutch derailleur for 9 speed; luckily, Deore XT 711 has quite strong springs. Like I said, I used a 11-28 cassette, however that is not quite possible if you live in  “mixed terrain”. Nevertheless, I never dropped a chain with this setup.

Ghetto setups, put together by “ordinary” MTB components works fine, unless you go for huge cassettes. First reason is obvious: older derailleurs are not designed to handle such big cassettes, well over 42t and up to 52t. Their reach is too limited. Second one is more tricky: their springs and design does not permit handling huge chain slack. Between, say, 50t and 11t, is roughly 51 cm! So, you need a very long derailleur cage with a strong spring tension to remove slack, when you’re in 11t gear.

However, rear derailleur with long cages can handle 1x setups with up to 11-36t cassettes, probably – I tested with a 11-34 cassette, without any problems.

For beater bikes, or very flat terrain, a carefully planned 1x setup is almost as good as 2x setup, not just providing enough top and bottom end, but also nice spread amongst gears. I’d happily convert a 3×8 old bike used for going to grocery store to 1×8 without much thinking.

1x is sometimes handy, because you can repurpose your old, high end cranks that have no use, because new chainrings are expensive as a new crank or not available. Grab a 10$, narrow-wide chainring from AliExpress and you have a great 1x crank at almost no cost.

Crazy idea for 1x

I was thinking of getting a cheap 3s rear gearhub, modifying it to accept a 10s cassette, effectively having 30s bike.

The benefit of such setup is, you won’t have to deal with front derailleur adjustment, and will have a more streamlined bike. If you are crazier, you can buy Campagnolo Ekar components, and pair it with a Shimano Nexus Di2 8 speed, effectively giving you 13×8=104 gears, with semi – electronic gearbox!

Of course, such setup will need crazy modifications, lots of time, lots of mistakes costing you huge sum of money.

Recently, a Belgian company, Classified, announced a 2 speed rear hub, which replaces front chainrings and front derailleur. In pactice, its a primitive and lightweight gearhub, coupled to a cassette.


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