why are motorcycle sat nav’s so expensive?

I know there suposed to be waterproof but that dosnt justefy the high price

A sat nav made for motorbike use is made slightly more rugged than one made for a car so that adds a bit to the price. Then there is the competition element – there are many makes and models available for the car market and this drives the price of car sat navs down. (It’s not so much a case of bike units being very expensive but rather that car units are very cheap.)

However a major cost factor is the map set supplied with the unit. Maps are frequently the main part of the total cost of a sat nav. Systems sold for bike use usually have maps containing much more information than systems sold for cars. The simplest maps will have only the information that a road runs from one point to another. Sophisticated maps will contain information on the type of road, its surface and other information that can be 10 or more times the information for a given stretch of road. This allows the user to select the type of route that the unit should choose e.g. avoid main roads and give preference to unpaved roads.

Routing is essential for most bike riders but is frequently of no interest to car drivers. If you wish the sat nav to guide you by the fastest route from where you are to an end address then cheaper sat nav systems are as good as any. For the motorbike rider who wants to plan and then follow a particular route, then the sat nav must support routing. Cheap sat navs are good for going from A to B which is typical for car use. Bike sat navs are good for going from A to A i.e. from home back to home but via a preselected route. This enjoyment of the road and the journey itself is now almost exclusively the domain of the bike rider,

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