How to clean and brighten reflective wall tires I have a set of Continental Touring tires with the white reflective stripe on the sidewalls, and they get pretty dirty with road and brake grime.  Normally I would clean with car soap and water but sometimes it doesn't get all the dirt off/make them look new.  It is also winter right now so it is harder to soap and water wash in the garage.  I did use a washcloth and clear water from bucket. It helped a lot but still a long ways off.  Is there a way that I can make the stripe clean and bright white again?  

NOTE:  The reflective strip on these tires are a tape that is added to the tire.  I have another bike with different brand tires where they might be painted on.
Hit the tires with a bush and some concentrated soap.
In the dark shine a light on them and you would be surprised how much they shine even if they look dirty.
Once you scuff em up bad then just time for new tires.