I have a 04 800ss. Was a salvage/ theft recovery bike that needed new ignition, gauges, chip. Instead of spending the $3700 in parts from local dealer I found a set on ebay for $500. Great deal only problem is they were from a 04 s2r 800. Bike runs good I'm just concerned with any problems this setup might cause. Anyone know if they are compatible or know of any other modifications I might need to make to have these work? Also if I decide to upgrade the exhaust what should I get s2r or 800ss chip, or will a power commander do the job. I know it depends on the exhaust I go with but still confused. Almost forgot the tach works fine but speedo is off by about 25 mph. Any ideas?