Can anyone tell me if I can date an engine from the number. I am looking at buying one and want to double check the date of it first.

Otherwise what are the physical differences between 2003 and 2004. I know the internals are quite different and the latter revs higher with a little more bhp.
Searched by google but can't find nowt.

Thanks in anticipation as they say.

2003 would have 5PW stamped on the engine block, 2004 would be 5VY

The 2003 will be marked as 5PW, not sure on the later ones. You need to be careful though as some parts on later engines are marked with earlier model codes, for example some of the bits on the 5PW are marked 4XV as they are parts carried over from previous models.

They are very different engines though, the 2003 engine is very upright with the cylinders quite vertical in comparison to most bike engines, whereas the 2004 engine has the cylinders much more canted over.

Here's an older engine, not sure if its 2003 but they are very similar from 98 to 2003, and the basic block is the same I think



Im sure a google etc would throw up a similar one for the later engines

[Edited on 9/1/07 by ChrisGamlin]

Hi 2002/3 injected r1 engine no,s start
N506 to N508 later 2004 to 2006 start N509 to N512 also early ones are black covers and head and silver crankcases later are all black except sump pan unless its a 06

cheers malc

Thanks v much, I knew you would have the answer. Particularly malc for giving the atcual numbers..........

The one is Chris' pic is a 98-99. It has no AIS yer see!