How many gears do we really need on a bike

[Dogtrousers]

I was wondering when, @ColinJ and his gearing freak show would turn up.

 

[Punkawallah]

Can only use one gear at a time, ergo only one gear is needed.
Can only use one bike at a time, ergo only one bike is needed.

IGMC

Heresy! Burn them before their vile contagion spreads! :-)

 

[8mph]

20 to 24

 

[Ajax Bay]

Given you can now get carbon frame bikes with 105 Di2 (12 speed), for around £2000, I think it is definitely moving into mainstream territory for keen cyclists. Not even close to a majority of bikes sold, but much closer to a majority of those bought now which will be regularly used on the road.

Incidentally, to answer the OP, you need as many gears as will provide reasonable gaps between the lowest you need and the highest you need.
What the lowest and highest you need are will depend on what terrain you ride, how fit you are, what sorts of loads you carry, and your purpose in cycling. Probably other factors as well.

Last two sentences: great answer. Can you do as well defining a "decent" bike for road use, and also "keen cyclist"? Clearly 12sp systems will slowly increase in number (a tiny minority of road bikes): does that mean they are "moving into the mainstream"? It's only because there are even more extreme systems being marketed that they're not completely on the edge.
I've looked for data but not found.
What's your recommendation for "a carbon frame bikes with 105 Di2 (12 speed), for around £2000"? Think maybe mechanical 12sp there'd be options but, as you suggest, what "keen cyclist" who "regularly rides on the road" buys a bike with 12sp and mechanical gearset nowadays?
https://road.cc/content/feature/six-best-bikes-12-speed-ultegra-8100-291189
https://road.cc/buyers-guide/best-road-bikes-under-ps3000

 

[Fab Foodie]

One is enough

But a really good one....

 

[Alex321]

Last two sentences: great answer. Can you do as well defining a "decent" bike for road use, and also "keen cyclist"?

Probably not.

For me, a "keen cyclist" would be one who rides at least weekly, probably more, and not just because they have to or for utility reasons.

As for a "decent" road bike, it would be something said keen cyclist (assuming their preference was road for this bit) would be comfortable riding for the length of their regular rides, and which they didn't feel was holding them back due to weight or components.

Clearly 12sp systems will slowly increase in number (a tiny minority of road bikes): does that mean they are "moving into the mainstream"? It's only because there are even more extreme systems being marketed that they're not completely on the edge.
I've looked for data but not found.
What's your recommendation for "a carbon frame bikes with 105 Di2 (12 speed), for around £2000"? Think maybe mechanical 12sp there'd be options but, as you suggest, what "keen cyclist" who "regularly rides on the road" buys a bike with 12sp and mechanical gearset nowadays?
https://road.cc/content/feature/six-best-bikes-12-speed-ultegra-8100-291189
https://road.cc/buyers-guide/best-road-bikes-under-ps3000

https://www.sigmasports.com/item/CUBE/Attain-GTC-SLX-Disc-Road-Bike/ZW1W

I have an older version of that, with 11 speed 105 mechanical, which cost me £100 more than that one, in August 2021.

 

[matticus]

In the early days there were bikes with two gears where one of the gears was engaged by pedalling backwards. (Retro Direct)

For cycling that is done purely for exercise that might be a good thing to bring back as I'd imagine that backwards pedalling under load would add a new dimension to the workout.

https://retrodirectbike.com/

... and I'm sure it doesn't need pointing out to the learned assembly on this thread, but such a bike has been used to complete Paris-Brest-Paris in under 90hours (by a less-than-youthful amateur)

 

[Dogtrousers]

... and I'm sure it doesn't need pointing out to the learned assembly on this thread, but such a bike has been used to complete Paris-Brest-Paris in under 90hours (by a less-than-youthful amateur)

I didn't know that. I will get googling.

 

[presta]

Walking home from Tesco yesterday, a guy wearing a bright yellow rabbit costume passed me on a motorbike. I'm pretty sure that's not the right gear.

 

[sleuthey]

My daily hack is SS Oval Chainring with a ratio of 2:1 for riding through the Bristol suburbs only.

My Boardman hybrid is 1x9 being 40 upfront and 11-42 on the rear. It gets me up a very steep hill coming out of the Frome Valley in 2nd and I go down it at 30mph in 8th.

Thus I have no need at all for a double/ triple chainring. Nice and simple.

 

[Dogtrousers]

I'm surprised we haven't discussed the Classified Hub, a 2 speed planetary hub gear and so called "Front mech killer". Or did I miss it?

Planetary hub gears have - at a stroke - gone from things that were on your grandma's shopping bike, or are used by beardy, sandally long distance tourists from Germany, and are far too heavy and inefficient for proper cyclists (TM) to even think about - to being cool and trendy front mech killers (grrr) costing €2,400 and used by Filippo Ganna.

Now I'm not a knee-jerk luddite, I love new stuff (even if I don't use it) but even I have to ask "why".

Why has the world become allergic to front mechs? I can see how, on mountain or gravel bikes ridden over bumpiness, they might be a bit prone to dropping the chain. I don't know I've never done that. But I have ridden a lot on the road and I never (well, almost never) drop my chain. And anyway, the last time I can remember seeing a pro drop their chain it was Roglic in the Giro last year - on a 1x. Front mechs are about as maintenance free as can be - set them up right and forget them. Add a bit of oil to the pivots when you clean the bike. They are cheap. I put "Dura Ace Mechanical Front Mech" into google and it said they cost £70. That's virtually free for something with "Dura Ace" written on it. Tiagra front mech seems to cost £30.

And if you don't want a front mech then go for a 1x system. But why in the name of Sheldon would you go for a hub gear that does nothing that a double can't do (except cost €2400)

Edit: I've found out why. It's because "Shifting chainrings is quite slow, can’t be done under power, and requires a certain amount of consideration of the chainline." So that's me told. What a load of rubbish. https://www.cyclingweekly.com/reviews/classified-powershift-hub-first-ride-review

 

[Fastpedaller]

This is my 3x9 transmission. As you can see, you could get away without any middle ring at all, but it would mean an awful lot of annoying switching in the middle of the range where you spend most time.

View attachment 732034

A closer ratio cassette eg 13-21 would give you almost as good range and lots of closer-ratio useable gears?

 

[dicko]

I cycled for seven years with a single speed back pedal brake cycle you just get used to only having no gears.

 

[Ian H]

... and I'm sure it doesn't need pointing out to the learned assembly on this thread, but such a bike has been used to complete Paris-Brest-Paris in under 90hours (by a less-than-youthful amateur)

Twice, I believe (out of six on various unsuitable machines).

 

[rydabent]

All 3 of my rides have a triple. My shifting sched is simple. Granny ring up hills, center ring for the flats, and big ring for down hill with the wind. Shift across the rear as needed in those 3 situations.