Interchanging parts between two gens is possible. Obviously, engine parts are going to be tricky, as will as other obvious parts. There are two ways to find out if you can swap/upgrade parts. This is to find a parts manual for said years. The other is hands-on-experience. This is more where this thread comes in.
When parts are refined during the production run of a particular engine family, these part numbers may change, but the fit is still the same, usually. An example would be: the air cleaner element access door was made of plastic, then changed to aluminum, and now a pressed steel cover.
My kind of guess of stopping so much confusion is to call the 14 the first gen, then the R being the second gen. This is how one should describe what you are looking for, explaining you have a 14, but want to use an R part... Will it fit?
My kind of direction is to begin at the front wheel and work your way back. It's been a slow process, but I am on my 3rd 14. I'm a few meguveers away from finishing off the rest of the 2013-R. For now, this is how much I know.
Front Wheel Assembly:
Yes ~ Fit any year rim up to any 14/R.
Yes ~ Use any other parts off the entire front end and swap between any 14/R.
??? ~ Let me post another or someone can add if the disc diameters are the same? The carrier may look the same, but the disc may have grown outward? That means they grew the lower brake carrier legs outbound to make up the difference. Sans the entire front end swap, the meguyveer move is to 'shim or shave' to make either work.
Frame:
Yes ~ Fits any year R.
??? ~ No one has tried swapping a 14 into an R or vice verse.
Yes ~ Rear shock fits any 14/R
Rear Wheel Assembly:
Yes ~ Fits any year 14/R.
Yes ~ Rear brake system interchanges with all brake panels, axles, etc.
Body Parts:
Yes ~ Fit any R to an R body/tank/winks/etc.
No ~ No front panels, no side panels, no lower panels, no upper nose; fits between a 14 and R.
Yes ~ Front fender fits any year 14/R.
Yes ~ Rear winker pods interchange between 14/R.
Yes ~ Gas tank fits between 14/R.
Yes ~ Any year seat fits between the 14/R.
Yes/No ~ Rear fender injection mold is slightly different. Either match 14 to 14, R with R, or meguyveer to fit either.
Electrics:
Yes ~ Any wire harness, throttle body, ECU, handlebar switches, interchange between R/s.
No ~ Gen 14's and Gen R's: must stay with their required FI systems. That means the ECU and injector must match.
Yes ~ Use any fuel pump in any R or 14 tank.
No ~ Throttle bodies are two different animals between each other. Meaning, you need to match any R part off an R throttle body.
Engine:
Yes ~ R interchanges with R.
Yes ~ 2006-2007 14's interchange parts internally only.
Yes ~ 2008-2011 14's interchange internally, where the first two years had different teeth angles at the clutch to crank's interlocking gears.
This is as much as I know so far between interchangeability of 3 different generations I've owned so far. So if you are thinking of attempting some crazy things between bikes, some you can, some you can't. Well, if you have money, anything is possible, right?
