Now that my local dealer has said no more 690SMCs are coming until February, I am looking at other 690s. Are there any differences between the 2007 690SM engine and the 2008 690SM or Duke? Why does the Duke have more HP? Also, the frame and swingarm seem very similar. Are the bikes the same other than the headlight, exhaust, wheels and obvious stuff? You know, like the 690SMC and 690E are the same. What I am getting at it am I giving up anything on a 690 SM instead if a Duke? And could I put a Duke headlight and fender on an SM?