The only time it really concerns me is when I'm on an exposed gravel road and the wind is across the road. If its bad enough I'll ride in the ditch, its safer down there. Otherwise I'll ride in any wind. More or less have to do so on the prairies anyway.
So, you will have to add a few more increments to the scale on your poll.
Above 20 mph, 'cause it means the gusts are going to be above 30. It's particularly an issue with faired bikes. If you're at freeway speed, the wind's coming from one direction, then suddenly shifts and slaps the other side of the fairing with a 30+ gust, it can move you into the next lane before you catch it.
There was one day I was riding along in 45 mph winds, gusts up to 60, but I was behind some hills, then the hills started having ravines between them. Scariest thing ever going down the interstate and having to drop over when exposed to wind then straighten back up when not, all at 75 mph. I just turned around and came home... Wasn't worth it!
Have owned - 2001 Suzuki Volusia
Current bike - 2005 Kawasaki Z750S
MMI Graduation date January 9th, 2009. Factory Certifications in Suzuki and Yamaha
I don't know how to measure windspeed when I'm out there. I've been out when flags are flying and snapping in the wind, and I know that the weather people were predicting gusts of 25-40 mph--but the weather people here say lots of things that never pan out.
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