Triumphrat

Geimer

Hi,
I use a tarp from the hardware store which is about 8' by 10' with a drawstring sewn in around the outside. It was about $12.00 and made in the good ol' USA. I keep the bike under a "lean-to" that I built 20 years ago for the old Bonnie so it is open on the one side but hangs over enough to keep all rain out. The cover just keeps the dust from accumulating and the excrement of the carpenter bees off of the seat.
Even if you have to keep the bike outside sometime the drawstring keeps the cover in place in moderately high winds.

Good luck

P.S. just wait 10 minutes before covering if it's a plastic tarp. 10 minutes has always been enough to cool my headers below melting temp of the plastic.