Good question. I had my Honda Helix totally enclosed once back in 2009. The wind blew me around too much. It could be very scary at times.
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The Ninja 250 is different. It doesn't seem to be affected so much in side winds so it looks like the Ninjas
can have the sides covered over. Alan will be slowly adding sides onto his Ninja. He really wants to beat those Diesels.
I think the issue is the little Helix wheels and trail.
Craig