I have the Specialized S-Works helmet which...
I have the Specialized S-Works helmet which is slightly different then most bike helmets, will this helmet cover fit properly?
The large should be able to cover the Specialized S-Works helmet. Another option would be to wear the Signature GORE-TEX® cycling cap underneath the helmet.
Dave - GORE BIKE WEAR
I also have the new Specialized S-Works Prevail (LOVE IT!), and use Gore's thermo cap underneath (when it's cold/chilly) with no problems at all; plus, it covers better than just a cap on top of the helmet only.