I have just spent nearly two hours fitting a K&N Air Filter to my AN400!
WHAT THE F**K !!!
I am an ex-race mechanic with over 25 years experience, and I found it difficult!
The rear Air box retainers are a terrible design they could have been done so much simpler.
After a lot of trimming and filing I have managed to get them to slot in nicely with just a little thump.
Hopefully after the next clean & wash it will drop back in a little quicker.
On to the Oil change next that can't be as difficult?
Here's hoping
Cheers
Baz.

It took me ages when I did it too, the original seems to go in and out much more easilly.
I assume this is a post 2009 model as my 2002 was no problem.

Glad to hear in a way, I thought it was me!

Due to the crap air box designs and how restrictive they are I always fit. Ram air foam filters these are great for improved air flow and work well under body panels . I have just fitted an oval one on the srv direct to the throttle body . The difference is very noticeable and does not make as much noise as a k&n cone filter does in my experience . I have used them for racing over the years with great results .

Put the scoot on the side stand and the rear shock in the lowest setting this lets the engine drop a little and gives more room putting weight on the rear
of it also helps, it will fit better second time round, fitting a skirt in front of the rear wheel doubles the time it takes the filter to get dirty.