Growing numbers of mountain visitors are choosing to bike and there are prepared bike paths and trails in several places. Ask the local tourist information centre! There are no special traffic rules for biking in the mountain terrain. But most of the mountain trails are primarily prepared for hiking.
It is therefore reasonable that you yield to hikers if you are biking. Biking in the mountains demands skill, consideration of nature and a good mountain bike. A bicycle helmet is a given even if not biking so fast. There is a large risk of falling in steep terrain and on rocky and uneven ground. Stick to trails and well-worn paths to not damage the fragile ground cover.
The major difference between biking and hiking in the mountains is that one comes at least twice as far on a bike over a day than when hiking; one simply gets to see more of the mountains. On the other hand, it would be a lie to say that the Swedish mountain world is optimal to bike in; there are quite a few rocks in many places. It is important to really know where the good parts are, where that narrow path on the ridge runs or where the old goods road straight over the mountain is.
Some good sites for mountain biking
As an area, the paths and roads around Storulån in Jämtland are really good. As is Ramundberget/Bruksvallarna. There is everything from untrafficked gravel roads in wonderful mountain environments to narrow paths on a hard base without rocks. One section that many have as a favourite is the Rallarvägen route from Abisko, past the border and all the way down to the sea on the Norwegian side and the old goods road from Klimpfjäll up to Stekenjokk in Västerbotten.
Biking in the mountains demands a strong will, experience and good equipment. A mountain bike is a must and at least the front fork should preferably have shock absorbers. Always bring a spare tube and pump. A tyre can go flat and being forced to walk a long way with the bike is not great. And just like when you are hiking, you have to be prepared for changes in weather.
Organised group activities require the permission of the county administrative board, which can also help guide the activities to areas that have a minimal impact on the natural environment and reindeer husbandry.
In national parks and nature reserves, special regulations apply that can restrict the right of public access.