Hammerhead, maker of the Karoo cycling computer, has closed a $4.1 million seed plus round, led by Primary Venture Partners and KB Partners. Also participating were Courtside Ventures, Maveron, Robin Thurston, the co-founder of MapMyFitness and previously Chief Digital Officer at Under Armour, and Andy Ording, the CEO of Zipp.

In a blog entry, Hammerhead said the funding will support further development in Karoo’s software development.

“The next major innovation in cycling will take place in software. Great software has always been a focus at Hammerhead. The bicycle of the future will be intelligent and data-driven. It will guide riders to the safest roads and best trails. It will facilitate the right workouts to achieve an athlete’s fitness goals. It will speak to a world of connected sensors and it will facilitate smart fleet management for bikeshare,”  said Pieter Morgan, Hammerhead CEO, in a blog entry.

With further development, Karoo OS will enable other companies in the industry to easily integrate sophisticated software solutions at all levels, putting their own software experiences directly on the handlebars of the sport’s most engaged, competitive and ambitious riders.

This funding round also enables Hammerhead to rapidly expand its team, with several key positions open in its New York, NY, and Malvern, PA, offices.

Hammerhead started in 2013 and crowdfunded its first device, the H1. The hammer-shaped smartphone-connected navigation device for bicycle handlebars worked by flashing LEDs at turns but has been discontinued. Last year, Hammerhead launched Karoo, a bar-mounted GPS unit that supports navigation and training. The device features a high-resolution, anti-glare touchscreen and many connectivity options for uploading maps and routes.

Hammerhead has now raised a total of $7.4 million in reported equity funding.