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By AndyMc
#6936
Since buying an imported EFI a few months ago I have suffered an annoying and sometimes frightening flat spot on opening the throttle. This often made going round roundabouts very interesting when the engine would nearly stall throwing me off balance. This was made worse by fitting an Indian straight through exhaust.
Looking on our hosts website I saw an advert for an air filter cover insert which is often not fitted by the factory. I had wondered about the effectiveness of the air filter as air would be drawn into the engine through the airbox cover (no seal) and bypass the filter. Anyway, £17.60 and 5 minutes to fit later I now have a bike with a far smoother throttle response, no flat spot, but a little less top end power. The carburetter conversion can now be put on the back burner for now.
If anyone with an EFI opens their airboxbox cover and can see their air filter, they need one of these. Part No 591681
By Wayne
#64600
Adrian - sorry but you are referring to the air filter retaining plate, which is not the case with this plastic cover which does not hold the air filter in place but diverts air through the filter.
By Tim NZ
#64613
Or a couple of wraps of Colour coded electricians tape around the cover to seal it...


A known 'issue' since day One. The factory should have identified and corrected the flaw in the prototype testing phase back in 2007.
By AndyMc
#64616
This is a very neat solution. All I need to do now is to find an easy way to remove the stupid tea caddy storage cover on the other side so I can use it to store my lock and I will be a happy bunny.
By ric
#64639
Nice bit of problem solving :) Unfortunately this cover doesn't always seal perfectly against the inside half of the toolbox. Not only does this condition permit any emulsified oil to leak out but unfiltered outside air to get in (unless the two halves of the toolbox are sealed with tape)

One way to solve this is to modify the shape of the circular plate so it sits closer to the inner case. This holds the air filter tighter in place and also pulls the black plastic cover tighter in as well to form a decent seal. I placed mine on a reel of gaffer tape and gave it a few taps with a rubber mallet to move the centre section out by a few millimetres.
By ric
#64646
Oops a correction option on this site would be an asset. After originally tidying my message prior to posting, I've only just realised the sentence about moving the filtercover fixing stud inwards is missing. Ho hum.

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