air impulse sys removal ??

[grumpyone]

Can anyone tell me the air impluse system on our R80 1986 I have read it should be done away with?? How does one go about that and what all do you remove.??
What is the improvement doing this?
Thanks
Jim

[20774]

A thread on this earlier this year.

http://www.bmwmoa.org/forum/showthread.php?t=22989&highlight=%22pulse+air%22

[R80andR100RT]

I had the same idea for my 1985 R80. I bought the plug kit from Bobs and then decided to leave the air injection alone as I'm concerned about stripping one of the fittings in the head during removal. I think that would cause an enormous hassle.

[donbmw]

You can strip the threads but you can install and thread insert or heilcoil if this happens.

Don

[beemerguru]

I had the same idea for my 1985 R80. I bought the plug kit from Bobs and then decided to leave the air injection alone as I'm concerned about stripping one of the fittings in the head during removal. I think that would cause an enormous hassle.

Not a problem. Once they easily break loose, they come out with your fngers. Be sure to use locktight on the drain plug replacements.

This is a lot cheaper than waiting for your valves to recede from all the heat. When you take the valve covers off, is the front of the head a golden brown while the back is still aluminum colored? Too much heat.

[sumran]

I had the same idea for my 1985 R80. I bought the plug kit from Bobs and then decided to leave the air injection alone as I'm concerned about stripping one of the fittings in the head during removal. I think that would cause an enormous hassle.

I had the same concern, but went ahead with the job. It was a bit difficult getting the compression nut loose, so I was ready to put the system back on if was too difficult to remove the fittings. I was actually able to remove the fittings with my fingers. I have talked with others that were surprised at how easily the fitting came out.

One note of caution: You may have carbon build up around the fitting. The plug is a little longer than the compression fitting. Clean the area as well as you can with a round wire brush ( I used a battery terminal brush). Then install and remove the plug once or twice, clean again with the brush and then do your final plug install. On mine, the plug did not seat fully the first time I put it in.

[grumpyone]

Thanks much we will proceed to remove. One question tho I thought the pipe ran from the rear of the air box on each side to the exhaust pipe instead of the head. I have not looked only glanced at it when I noticed the bike had it on it.
Again Thanks for the world of info
Jim and Esther

[kourt999]

Just did this job on my 85 R80 (along with a lot of other things, like a spline lube, new starter, new coil, refit petcocks, new plug wires, etc.). Here's a photo from the middle of the job:

<img src="http://kourt.dehaas.com/bmw-spline.jpg">

I removed the tubes from the exhaust side of the head, removed the tube-to-head fittings (they were finger tight, as others have experienced), cleaned around those ports and inserted the new plugs. Tightened them and then tightened them again after the heads were hot from a ride.

I removed the various tubes and such to the airbox, and removed the old airbox. I replaced the old airbox with a Euro style airbox because I am picky about these things.

I tried using screws to plug the ports from the carbs but that turned out to be a pain in the butt to access for carb tuning, and the screws would vibrate loose, even with washers. Instead I cut the existing vacuum tubes down to 1" of length and plugged the open end with a wood screw that fit tightly into the exposed end of the tube. Now when I tune the carbs with the TwinMax, I just grab the 1" length of tube, yank it off and set it aside, exposing the sync port for connection to the TwinMax.

The bike got a lot of work that weekend and I pretty much had to retune everything from scratch. The bike is a little more fuel efficient, easier to start and has better midrange, but with all the work I did it would be stretch to say removing the pulse air system had anything to do with those changes. One thing that sticks in the back of my mind is that US spec BMWs of that era with the pulse air system had similar carb jetting <b>except</b> for the needle jet/mixing tube values, as derived from here:

http://www.bingpower.com/english/service/einstellblaetter.html

I'm not fretting about it too much, though. The airbox is definitely roomier now and between the new starter and the removal of the pulse air system the old girl probably lost 10 pounds of weight.

Careful study of the photo will reveal the Schumacher battery charger installed on-board, at the forward part of the rear fender behind the battery. I just plug an extension cord into the bike when I want to charge her up. Also, the valve covers are on upside down in this photo. Gotta get those things painted black again.

kourt