Quick summary for the important stuff that I do not think has been hit on.
COMPRESSION RELEASES
Not sure if anybody has noticed but the 08 1250's no longer have Compression Releases on the cams. They claim it is due to the larger battery since 07.
SLIPPER CLUTCH
Clutch basket is the same but the plates, hub, lifter plate, and pressure plate are different. These will retrofit to older models. Uses 4 clutch springs instead of 5 and requires a different clutch hub holder for removal.
HEAD GASKETS
New shape and material. Will not retro fit to older 1250's.
CLOSED LOOP EFI
O2 sensors are located in head pipes. Front and rear.
REAR SPROCKET
Changed to use the 25mm bearing and axle.
COMPRESSION RELEASES
Not sure if anybody has noticed but the 08 1250's no longer have Compression Releases on the cams. They claim it is due to the larger battery since 07.
SLIPPER CLUTCH
Clutch basket is the same but the plates, hub, lifter plate, and pressure plate are different. These will retrofit to older models. Uses 4 clutch springs instead of 5 and requires a different clutch hub holder for removal.
HEAD GASKETS
New shape and material. Will not retro fit to older 1250's.
CLOSED LOOP EFI
O2 sensors are located in head pipes. Front and rear.
REAR SPROCKET
Changed to use the 25mm bearing and axle.