Just saw that Benedict Cumberbatch cycling video and I ended up paying more attention to the bikes than the actual situation lol.
He was on a cargo bike with smaller wheels, and the other rider looked like he was on a city bike
if there’s a bit of distance between them but they’re basically riding at the same speed in city traffic, how did the other rider manage to keep up so easily?
Is that down to bigger wheels holding momentum better? Or just a lighter bike and more effort from pedaling?
I’m also looking to get one for city use, so I’d be curious what people would recommend or what you’d pay attention to when choosing one.
by Relevant_Wedding3812
13 Comments
Fuck the bikes, get out of the cycle path.
Also, get a single speed secondhand beater, like a Specialized Langster
while mostly depending on hubs, its the same logic as cars, smaller wheels are more efficient to a degree, larger tires go over obstacles better, but on paved roads its not much to consider. idk about safer but your center of gravity is higher and you can tip over easier at slow speeds, cargo bikes tend to be top heavy too
Think it’s just physics, besides the pot holes thing. Small wheel will be easier to accelerate but lose speed faster. Big wheel slower to accelerate but will lose speed also slower.
Yes big wheels will let you eat holes etc easier but ideally you should avoid anything like that in the first place.
I’ve got a brompton with 16” wheels and it’s just as fast an anything else.
… except on cobble stone street
If it’s an ebike they are anyway limited to a max speed for the assist to 25km/h, above that its up to the power in your legs. I recently switched to ebike for commute (the same one Benedict has as it happens) and i’m on average slower than my push bike just because i ride around the 25km/h limit to benefit from the assist while the old bike I’d push past 30+ – i could do that on the ebike but it’s heavy with all the kit that’s just dead weight above 25.
the cargo bike is an ebike, so it is electronically limited. and the limit of 15mph, 25kph or whatever it is in the UK, is a speed easily achievable by a decently trained cyclist on the flats no matter the wheel size.
edit: allegedly smaller wheels are banned in uci races, because their smaller size would offer an aero benefit.
Benedict’s bike is electric assist. It’ll be a tank to ride faster than 15.5mph when assistance tops out, so he likely only ever hits 20mph on downhills, and central London is pretty flat. Easy enough to ride along with for most regular bikes.
Why small wheels? Look at the overall size of the two bikes. Benedict can afford a lot in London, but space will always be at a premium, and he can stash that alongside a car in our smaller garages.
We have potholes and steps and kerbs to deal with, tyre volume is more important than diameter.
Edit: Benedict was obviously in the right here because http://lookatmyfuckingredtrousers.blogspot.com/
Cargo bikes only have small wheels because it gives frame designers lots of freedom to easily integrate boxes, baskets and load shelves the wheels can be strong with relatively wide tires without being too heavy. Smaller wheels would ordinarily be slower than larger diameters but gearing compensates.
The simplest answer is that it comes down to the gear ratio. With a small wheeled bike a taller gear ratio can have you pedaling at the same speed as a 700c bike for a given speed. Larger wheels roll more efficiently and smoothy over small imperfections, and have the best frame geometry for the average adult.
A 20-24″ wheel city bike is a compromise for a small size. Theyre much smaller if space is a concern in a city apartment, and to an extent more maneuverable in slow tight spaces. For cargo bikes the smaller wheels are stronger for heavy loads.
I actually put some 650b wheels on my gravel bike to fit MTB tires and they are actually so much better for riding in the city. They accelerate so much faster even with the higher rolling resistance tires. Since city riding is extremely stop and go and makes me wonder if they are honestly the better option.
wheel size and bike weight have essentially no impact on how fast you go on flat roads.
the main factors that affect how fast a bike is on a flat road are:
1. rider position and clothing (aerodyanmics)
2. tire construction (how low the rolling resistance is, this varies a lot)
3. bike aerodynamics. a bike with bags on it or very wide tires or whatever will add aero drag
Bigger wheels have lower rolling resistance. I ride a folding bike to work so I can easily carry it on the train. It takes a lot of effort to get to 14 mph and stay there compared to my other bikes with larger wheels.
If both bikes were somehow geared exactly the same, the 700c bike would be a lot faster. Bigger wheels mean more distance traveled per pedal stroke. Wheel size plays a big role in gear ratios.