B500 is speed limited and a very wide road, personally I would not recommend it. You may pick the smaller narrow and curvier roads nearby. If the wheater is good, I would always prefer one more day in the alps compared to B500 - the panoramic view is unbeatable. Strictly follow the speedlimit in Switzerland, the police there is not joking and you may become quick a poor man or even worse getting arrested and your bike confiscated for speeding.
Near Toblach you find Pragser Wildsee - I recommend a quick panoramic stop there. Also take maybe an extra day for the Sella round.
I didn’t go any further west of Grindelwald - I don’t know my way around there.
If you now load my alternative (https://kurv.gr/WxRyz) as an overlay, you can easily recognize the differences.
I hope you don’t want to start right away - some passes are not yet open!
Have fun! And no pictures please - they only make us jealous.
BR Wolfgang
Looks beautiful indeed!
I think it was in this forum that someone suggested I take the new one because of the better road conditions but when it’s dry, I will take the old one just for the sake of it.