I have an Oxford Rainex deluxe bike cover, size large, which I used for about a month on my Sprint GT before I traded it in for a T100. Very good condition and still in the hold-all in which it was purchased. £20. I'm about 7 miles from Hinckley factory.
Hi. To the best of my knowledge it's totally waterproof. It should fit a Tiger 800 but might be a bit baggy and could flap about about when it gets windy! It fitted my Sprint GT complete with topbox and panniers so it's pretty big! You're welcome to try it out - I'm in Bosworth Marina at Market Bosworth so not a million miles from Coventry. For my sins, I'm a Quins supporter!!
So am I, That's where I am today!! how far are you from the wasps ground? Would it be possible to meet up somewhere? Tomorrow, it would have to be after the game
I got the Oxford CV118 Aquatex Outdoor Cover with Topbox, Size: XL, as a Christmas present. It fits my Tiger Explorer with Top Box and Screen just fine. It says it is waterproof, but I've only put it on in the garage to keep the dust off. Packs down to about the dimension of an iPad but about 12mm thick. Seems like quite sturdy material as well.