For the average rider, inner tubes have been one of the most enduring and unchanging parts of bicycle design over the decades. They’re made of rubber, they have a Schrader or Presta valve, and they generally do an okay job at cushioning the ride.
However, if you’re an above-average rider, or just obsessive about your gear, you might consider butyl rubber tubes rather old hat. Today, there are far fancier—and more expensive—options on the market if you’re looking to squeeze every drip of performance out of your bike.
One of the ongoing rumors and scandals in professional cycle sport concerns “motor doping” — the practice of concealing an electric motor in a bicycle to provide the rider with an unfair advantage. It’s investigated in a video from [Global Cycling Network], in which they talk about the background and then prove its possible by creating a motor doped racing bike.
To do this they’ve recruited a couple of recent graduate engineers, who get to work in a way most of us would be familiar with: prototyping with a set of 18650 cells, some electronics, and electromagnets. It uses what they call a “Magic wheel”, which features magnets embedded in its rim that engage with hidden electromagnets. It gives somewhere just under 20 W boost, which doesn’t sound much, but could deliver those crucial extra seconds in a race.
Perhaps the most interesting part is the section which looks at the history of motor doping with some notable cases mentioned, and the steps taken by cycling competition authorities to detect it. They use infra-red cameras, magnetometers, backscatter detectors, and even X-ray machines, but even these haven’t killed persistent rumors in the sport. It’s a fascinating video we’ve placed below the break, and we thank [Seb] for the tip. Meanwhile the two lads who made the bike are looking for a job, so if any Hackaday readers are hiring, drop them a line.
If you exclude certain companies like Peloton, the world of cycling technology is surprisingly open. It’s not perfect by any means, but there are enough open or open-ish standards for many different pieces of technology from different brands to interoperate with each other, from sensors and bike computers and even indoor trainers to some extent. This has also made it possible for open source software to exist in this realm as well, and the GoldenCheetah project has jumped in for all of us who value FOSS and also like to ride various bicycles from time to time.
GoldenCheetah focuses on gathering data from power meters, allowing cyclists to record their rides and save them in order to keep track of their training performance over time. It works well with sensors that use the ANT+ protocol, and once it has that data it can provide advanced analytics such as power curves, critical power modeling, and detailed charts for power, heart rate, and cadence. It can display and record live indoor-training data, and in some situations it can even run interval workouts, although not every indoor trainer is supported. There are no social features, subscriptions, or cloud requirements which can be refreshing in the modern world, but is a bit of a downside if you’re used to riding with your friends in something like Zwift.
All in all, though, it’s an impressive bit of software that encourages at least one realm of consumer electronics to stay more open, especially if those using bike sensors, computers, and trainers pick ones that are more open and avoid those that are proprietary, even if they don’t plan to use GoldenCheetah exclusively. And if you were wondering about the ANT+ protocol mentioned earlier, it’s actually used for many more things that just intra-bike wireless communications.
Rear-view mirrors are important safety tools, but [Mike Kelly] observed that cyclists (himself included) faced hurdles to using them effectively. His solution? A helmet-mounted dual-mirror system he’s calling the Mantis Mirror that looks eminently DIY-able to any motivated hacker who enjoys cycling.
One mirror for upright body positions, the other for lower positions.
Carefully placed mirrors eliminate blind spots, but a cyclist’s position changes depending on how they are riding and this means mirrors aren’t a simple solution. Mirrors that are aligned just right when one is upright become useless once a cyclist bends down. On top of that, road vibrations have a habit of knocking even the most tightly-cinched mirror out of alignment.
[Mike]’s solution was to attach two small mirrors on a short extension, anchored to a cyclist’s helmet. The bottom mirror provides a solid rear view from an upright position, and the top mirror lets one see backward when in low positions.
[Mike] was delighted with his results, and got enough interest from others that he’s considering a crowdfunding campaign to turn it into a product. In the meantime, we’d love to hear about it if you decide to tinker up your own version.
You can learn all about the Mantis Mirror in the video below, and if you want to see the device itself a bit clearer, you can see that in some local news coverage.
We tinkerers often have ideas we know are crazy, and we make them up in the most bizarre places, too. For example, just imagine hosting a website while pedaling across the world—who would (not) want that? Meet [Jelle Reith], a tinkerer on an epic cycling adventure, whose bicycle doubles as a mobile web server. [Jelle]’s project, jelle.bike, will from the 6th of December on showcase what he’s seeing in real time, powered by ingenuity and his hub dynamo. If you read this far, you’ll probably guess: this hack is done by a Dutchman. You couldn’t be more right.
At the heart of [Jelle]’s setup is a Raspberry Pi 4 in a watertight enclosure. The tiny powerhouse runs off energy generated by a Forumslader V3, a clever AC-to-DC converter optimized for bike dynamos. The Pi gets internet access via [Jelle]’s phone hotspot, but hosting a site over cellular networks isn’t as simple as it sounds. With no static IP available, [Jelle] routes web traffic through a VPS using an SSH tunnel. This crafty solution—expanded upon by Jeff Geerling—ensures seamless access to the site, even overcoming IPv6 quirks.
The system’s efficiency and modularity exemplify maker spirit: harnessing everyday tools to achieve the extraordinary. For more details, including a parts list and schematics, check out [Jelle]’s Hackaday.io project page.
If you’d like to measure the speed of your cycling then it’s easy enough to buy a cycle computer, but as [Clovis Fritzen] has done it’s also an option to build one. The result of his work is a smart PCB on which the speed is indicated with a row of LEDs.
The sensor is a straightforward affair, a reed switch with a magnet on a wheel, which is sensed by an ESP8266. The six LEDs are charlieplexeed over three lines. To keep the supply voltage correct for the ESP from the uncertain state of a lithium battery, a small buck-boost module is used. Sadly the code doesn’t seem to make the speed available via the wireless part of the processor, but we’re guessing that a bit of extra software work could fix that.
One of the problems of being a cyclist is that a bicycle just isn’t designed to carry much more than a human. You can get panniers and hang shopping bags from the handlebars, but sooner or later there’s a load which just doesn’t fit. At that point there’s only one way forward that involves staying on two wheels: find a bike trailer. If you fancy building one yourself, then there’s La Charette (French language, Google Translate link), an open-source three-wheeler design from France.
Construction is a sturdy welded box section tube spaceframe, with the single wheel at the front providing steering, and a towing bar attached to the seat post of the bicycle. Along with the impressive load capacity comes the problem of towing it, and for the cyclist with less-than-superhuman strength there’s the option of an electrically-driven front wheel. Stopping the whole thing is an essential feature with loads this size, and to that end there’s an inertial braking system operated by the force on the towing bar.
All in all it appears to be a useful trailer, albeit on the large side for storage when not being used. It’s certainly one of the larger bike trailers we’ve seen, though not perhaps the most stylish.