If you have a clear shield on your motorbike you may wish to use the cleaners and polishes that work for that. A while ago I researched the plastic polishers to clean the Plarail clear tunnels and for the domes on the Knapford station and bought this set from Novus. I really like it and often use it on these Plarail trains and rolling stock when I get used ones that are scratched and could use a good polishing. And its good for plastic motor bike windshields. I have the 8 ounce bottle set but they also have the set in a smaller 2 ounce kit for less. There are tons of offerings on Ebay as well on Amazon. There are also many videos on YouTube.
http://www.ebay.com/sch/i.html?_from=R40...5573.m1684
https://www.amazon.com/s/ref=nb_sb_noss_...ords=Novus
https://www.youtube.com/watch?v=certTu6ETWw
http://www.ebay.com/sch/i.html?_from=R40...5573.m1684
https://www.amazon.com/s/ref=nb_sb_noss_...ords=Novus
https://www.youtube.com/watch?v=certTu6ETWw