I go off on long solo remote rides and so tend to over carry stuff.
On me, I carry my wallet, SPOT, and always wear a dog tag with emergency contact info.
Under the windscreen is my phone and the gps mounted beside the Koso gauge.
In the tank bag, debit and credit cards, pen, ear plugs (when not wearing them), leatherman, whistle, and minimag, and a Tupperware box filled with munchies.
In the backpack, 2-4L of water, iPad, sweater, and outer layer of my mesh pants.
In the tail bag, boot rain covers, outer jacket, air pump, fix a flat goo, oil, chain lube, WD-40, visor wipes, first aid kit, mag light, knife, sun screen, towel, space blanket.
Under seat cowl, inner rain liners, tire repair kit, disk lock, modified tool kit, and bike papers and owners manual.
Still have a few things I need to find homes for.
