As far as i know clothing law is down to a helmet. (But some of us are a lil shy so we kit up a bit moreso.) however seriously, when you look at the riders my guess is that the average age would be 60 plus a fair bit. so yep we tend toward the full jacket, plus Kevalar dacks, boots, gloves etc. mainly to protect us from snake bite if we have an off... but drifting back more seriously again, Jackets are surprisingly cool, when the winter layer is removed. Besides, the sun and windburn on bare arms / shoulders would be horrific over several hours in our summer climate. add to this the joy of road train traffic (imagine a semi with 3 trailers either coming at you or overaking you at 110km, which can generate a massive wind vortex) and road surfaces that, should one be unfortunate enough to have a spill, are akin to stopping your belt sander by turning it upside down n sitting on it in your shorts... n yep, we tend to dress to survive. hope that helps.