Airbox removal or modificaiton

[headwindjaz]

Hi All, I have just recently purchased an 84 K100RS and am going to do a cafe racer conversion on it. Iv been researching for quite some time and am now looking at options for the airbox. I wanted to remove the airbox and put a pod filter directly into the MAS. In working out how to mount the MAS outside of the airbox and wondering for those who may have done this before - how you connected the mass air sensor to the air plenum without the 90 degree rubber elbow that connects the MAS internally in the airbox which I hope to remove. Any ideas, pictures would be greatly appreciated.

I was also wondering if anyone had used an after market MAS to replace the original one ?

[Chaos]

CC Products used to make a plate with a flange on it to mount a pod filter, I've had this on on mine for the last 3 decades.  Wouldn't be hard to fabricate.

[Laitch]

Welcome, headwindjaz!

In addition to Chaos's example, there are other are photo examples on the site of intake conversions using air flow meter reorientation. They'll come up using a site search. Changing to an aftermarket meter or sensor would probably require modifying the fuel injection control unit or replacing it entirely—a technical and perhaps costly endeavor. There does not seem to be much information on modifying the Jetronic that's in your Brick. When the Motronic was introduced in the 16V Bricks, the intake air system was changed and removing the entire plenum became an option for customizers.

What's the odometer reading of your project moto; do you know its history?

[headwindjaz]

Gday Laitch & Chaos,

Thanks for your info. I really only was enquiring about an aftermarket sensor as im in Oz and K parts are not that easy to find. Im not sure if the MAS is in good working order or not. I guess in saying that there will be motorcycle wreckers that have parts.

Ill have a good look on the site to see what conversions I can find. Im not that opposed to leaving the original airbox in place, but when I got the bike the airbox has all these holes drilled into it below the filter for some absurd reason. I cant work out why that was done.

The history of the bike is a bit of a mystery. All I know is "it used to run, but I got another bike and pushed it to the back of the shed a few years back". It was missing a few parts when I got it, being the instrument cluster, CDI, fuel filler cap and a few other cosmetic parts. I cant complain in any way as I got it at the right price knowing what I was purchasing and enjoy the challenge of a resto.

My main reason for the conversions the airbox has had its own attempt at modification so I was really exploring options.

Thanks again for sharing your thoughts.

[Laitch]

Im not that opposed to leaving the original airbox in place, but when I got the bike the airbox has all these holes drilled into it below the filter for some absurd reason. I cant work out why that was done.

Thank for the background, hjw. You needn't wrack your brain. If you can work out how to post a photo of all this by using the Photo Guidance instructions, we'll come up with some kind of explanation, accurate or not.