All of which brings us to cost. Bikers are a famously frugal bunch and the Rider severely tests budgets thanks to its £350 price tag - more than any other sat nav in TomTom's range. Some of this can be justified through the rugged construction, but we don’t feel it is fully accountable given the lack of Live functionality, speakers and bitty Bluetooth implementation.
That said, main rival Garmin is even more expensive with its zūmo 350LM and 660LM coming in at £369 and £499 respectively. In their favour, Garmin supplies its own excellent ‘BaseCamp’ route planning software and Tyre (pictured above) is compatible. Meanwhile, the 660 delivers turn-by-turn directions when paired with a smartphone to offset the £50 to £100 cost of buying a decent headset.
Despite this the biggest threat to the Rider comes from the smartphone itself. Turn-by-turn GPS is now free on Microsoft, Google and Apple devices and even TomTom's own app for Android and iOS is just £36.99 for full European coverage. Unlike the Rider the TomTom app updates wirelessly, offers Live functionality with HD traffic, speaks directions through earphones and headsets and allows calls and music. A waterproof, touchscreen compatible mount like the So Easy Rider sticks just €39 on the total outlay.
Of course there are compromises. The Rider offers better readability in direct sunlight, has the Winding Roads shortcut and simple ways to create and share bespoke routes, but the app saves carrying a second device and it is adding new functionality all the time. Most phone mounts also have space for a portable battery, so battery life isn't a problem and your app transfers should you change or damage your phone.
The TomTom Rider v4 is a capable bike sat nav, but it has a number of faults. The company’s traditional strengths are all here to be admired: excellent build quality, good route mapping and a regularly updated map full of POIs. But the trouble is less what is there and more with what is not. In particular the omission of external speakers and HD Traffic are disappointing given it is the most expensive sat nav TomTom sells. We would also like to see it pair with a smartphone to deliver turn-by-turn directions through earphones, not just a dedicated headset. It's still a very good option to intrepid bikers, but it doesn't do enough to justify its price tag for casual riders.