How rare is the S4 Senna? Seems to me that its not very rare, that the majority I have seen on the posts have a S4 Senna and all the S4's you see on Ebay are a Senna. Seems to me its the other colors that are rare on the S4. I keep hearing the rare S4 Senna I see that people put it in thier posts on Ebay. Maybe its just a ploy to try and sell thier bike on Ebay.