A few ideas from the UK.....but first a question: When you say Europe, how broadly do you want to get known? For example, is the UK your main target, or the UK + Germany (big V-Strom market), or the whole European shooting-match?
1) Contact all the V-Strom (and general bike-related) sites you can find in whichever countries you're interested in and ask them to link to your site. Most will do this for free if you also link back to them in return. I've added you to the list of links on the V-Strom Owners Club UK
site for starters.
2) To advertise very directly in your target countries, without spending a fortune, Google Adwords
would be a good option.
3) In the UK, the number 1 motorcycling newspaper (weekly) is Motorcycle News
. There are opportunities on their website for free "Readers News", but your best bet would be their conventional paid advertising.
4) Contact the moderators of other V-Strom forums (I won't link to them here) to ask if you can post a message about your service.
Hope that's of some help. Good luck with the new business.