Mk3 air box

Hi all,
Well, my Mikuni carb kit arrived from Bill at Rocky Point, and after answering a carefully worded invitation from our Border Force to give them seventy quid I set to this afternoon to fit it. This is my first big job on my mk3, and what an education it is proving to be! After 2 1/2 hours I've got the carbs & manifolds off and the air box loose, but I can't for the life of me see how this plastic horror is coming out. I've taken the starter motor off which has made a bit more room, but it looks unlikely that it is coming out forwards.

Has anyone done this job, and remained sane enough to tell the tale? If so, please share the secret! I really want to take it out in one piece, if it's possible.

Cheers, Jon

My Mark IIA had the same basic plastic airbox as yours. I removed mine about 15 years ago so my memory is a little vague about how I removed mine. As I recall though I ended up removing the oil tank to get more clearance. I am not sure if I had to pull the battery tray out or not, I just removed whatever was in the way until it finally came out. One thing I do know is that you don't have to remove the engine to remove the airbox. Also there is a mounting tab on the top of the airbox, go ahead and remove that so it is out of the way. I wish I could remember if the airbox came out between the frame tubes and the engine or out through the oil tank area. I just don't remember. Rest assured it can be done without destroying the airbox. Good luck!

Hold the press - it's out! With the starter motor out & both metal brackets removed, I was able to pivot it forward then, with a modicum of brute force & squishing, rotate it out towards the timing side. Hurrah!

Thanks for your reply PJ, it gave me hope!

Cheers, Jon.

I have found that the best way to remove the airbox is to remove the battery and looosen the battery carrier. The airbox can then be angled down and pushed towards the front . It takes some wiggling but it can be done !

Alright, you got the airbox out! After thinking about it last night I do remember that I did remove the battery tray so that I could put two nut plates on the forward part of the battery tray so that I could mount the earlier type airbox. Here is a picture of my modification:



When I took the bike out for the first time without the big black plastic airbox my battery fell over on its side while braking on a steep downhill. This briefly shorted the negative terminal to the frame causing my engine to die. It's amazing that I didn't fry any wires. So I removed the battery tray once again to do an additional modification. I added battery strap brackets to the battery tray so that the battery was held down by two battery straps instead of one. Here is a picture of my modification:



Of course there are other ways to deal with the potential battery tip-over.

The Mark III battery is bigger than the battery used in the Mark IIA so it may not have the tip-over problem I had. However it is something you may want to consider. For instance you may want to make a storage box to fill that area where the original airbox lived which would prevent the battery from tipping over and give you extra storage to boot.

Hi,

I got my old airbox out without removing the battery tray by just removing the fixing bracket on the box by drilling the pop rivets out. By squishing the box it and came out

The next thing you need to consider is how to mount the LH side panel as it was fixed to the old airbox. Now it needs a new bracket which I made myself.

There are threads on this and some good pictures of example brackets.

Regards,
Sean

Player#3 said:

........The next thing you need to consider is how to mount the LH side panel as it was fixed to the old airbox. Now it needs a new bracket which I made myself......There are threads on this and some good pictures of example brackets Regards, Sean

Click to expand...

Or there is the one that you can just buy from oldbritts

Boxerfan, I've sent you a PM.

Hello ,
I know its a bit late but for anyone else out there this is how i got my airbox out yesterday.
Remove carbs and manifold ,
Remove starter motor,
Remove oil tank bolts ( you may not need to actually do this but I did anyway for a bit more wiggle room ),
Remove the cylinder head oil feed line support bolt / spring , ( not banjo fitting )
Remove airbox bolts / nuts ,
Rotate the bottom intake side up , and then rotate to the right as if you are trying to push it out the right side as much as it will go , keeping the engine earth lead and head oil feed lines clear ,
Then bring it back out the left side / timing side , and voila , Its out .
Its very tight and requires finessing but I didn't need to be too brutal about it , and no need to cut tabs or remove battery tray .
Now to fit the Mikuni carb
Cheers
Bal