I would suggest that buyers are attracted to the V7 variants and some of the Triumph range of motorcycles purely by the nostalgic appeal of their design. All V7's look small, have a low seat height and an apparently simple engine, all of which basically adds up to a user friendly motorcycle version of a scooter. The new Fiat 500, VW Beetle and BMW Mini models sell well by relating to past models even though they have no direct lineage. This nostalgic approach has stood Harley Davidson in good stead for more years than could reasonably have been expected. Find a simple design that works, build a cult around it then just sit back watch the cash roll in. They've only hit trouble when they tried to be clever or change something.
You'll notice that both Moto Guzzi and Triumph have produced relatively large capacity engines with power outputs which would be considered somewhat disappointing from any other manufacturer. This cannot have been entirely down to lack of engine development. Moto Guzzi would have known that these models would have more appeal to riders who place a sense of style over performance. As a result we have motorcycles that are adequate in most areas but extremely rewarding and fun to ride within their limits. What more could you want? Small improvements are the order of the day as has been seen with the new models, but these have probably been driven more by costs and legislation rather than a search for performance increases.
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