My brother and I both have single cam 08 reg bikes. Mine has 55K miles and feels a lot more free revving but can be buzzy through the bars. His felt smoother but comparatively sluggish.
I rode them back to back this morning. His taller Kahedo saddle is more bottom friendly than my standard height Kadeho.
Even with my Rox anti vibe handlebars, his bike feels smoother than mine.
His gearbox is better than mine. (easier shifting and less likely to clunk
Mine has a Power Commander but feels a whole lot more free revving. It can't just be the fuelling. Cant it?
His Metzler Tourance tyres with similar tread wear to my Conti TKC-70 feel very slow to turn. They make the bike feel heavy
Mine has a 55K front shock and a 30K rear shock. Both of his shocks have 20K
His bike was pootled about from new doing a few holiday tours and about 10K miles in 4 years. Mine was properly ridden by its original owner and used for commuting doing 35K in 4 years. Brother's bike has free'd up a great deal but I suspect the engine is still tight even though it has 25K on the clock. I would like to see comparative power figures with and without the Power Commander.
Overall my bike feels a lot lighter than his yet they are virtually identical models. It can't be entirely that mine was run in properly and his was allowed to stay tight.