This article first appeared on BikeRadar
The power meter market has been blowing up over the last couple of years, with the likes of Stages Cycling and then 4iii pushing the price boundaries and creating a surge in affordable training devices. Having just launched a crowdfunding campaign on Indiegogo, UK-based startup LIMITS looks to be the cheapest and most universally compatible power meter yet.
With a CNC machined CroMoly housing, LIMITS is a 47g left-based power meter that works by threading in between a standard 9/16in pedal and crank. This simple design means that LIMITS claims absolute compatibility with all standard pedal systems (more on this later) and cranks – regardless of mountain bike or road. Further to this, the outward placement of the meter ensures there’s no chance of interference from tightly-spaced frame designs.
The LIMITS will be available in black or silver
Having launched the campaign just a day ago, LIMITS has already raised 50 percent of its US$100,000 goal. The product is currently available for early backers on Indiegogo from just US$249, with the expected retail price to be a market-winning US$384. First shipment of product is currently scheduled for December, with a full public release expected early 2016.
Being left-based like Stages Cycling or Garmin's Vector S, the meter is likely to take the simple formula of the output from your left leg and double it. LIMITS' claims future editions are likely to offer a left-right version for independent power measurement. In the meantime, a dummy spacer will be supplied to use on the right crank to even out the spacing from the left.
Using 'four high accuracy strain gauges', LIMITS claims to record in a power range of 0-2000W with an accuracy of +/- 2%. Along with being left only, there are a few other features that we first saw from Stages Cycling, including automated temperature compensation and a built-in accelerator that measures cadence without the need for additional magnets.
LIMITS' has decided to go with ANT+ wireless protocol for the first version, so compatibility with most Garmin Edge, Magellan and many other cycling head units is expected. Bluetooth compatibility is said to be something that will come in future releases and developments.
Using a coin cell battery, battery life is claimed to last for a years' use. This claim is a little vague, but at least battery replacement is claimed to be easy with just a 2mm hex key needed.
The unit is said to have a IPX7 water resistant rating, which means it'll withstand being submerged in a meter of water for 30 seconds.
Easy installation and market-beating price is major, but the design is not without its limits (sorry). What may turn out to be the deciding factor of this design is the effect it will have on pedal stance width (aka Q-factor). The exact width increase is not yet known, but LIMITS answered this concern by stating that its research shows the device “allows the cyclist to ride with a stance width that is comfortable and so allows the knee to track on the most vertically linear path as possible […] it stands to reason that this action will put power directly down through the pedal".
How do you install a pedal that needs a hex key?
Another concern we're awaiting clarification on is actual pedal compatibility. From the company’s video, it looks as though the LIMITS's meter is tightened from the back of the crank arm, which would render many higher-end pedals –which require a hex-key for installation – useless. Of course, lower end Shimano pedals and all Speedplay pedals that use a 15mm open spanner will work without issue.
Lastly, LIMITS' claims the unit is up to the task of mountain biking, but looking at the ends of a crank arm on a well-used mountain bike should raise the question on how well the unit will be able to withstand semi-regular direct knocks.
Find out more at the LIMITS Indiegogo page.