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Classic Bavarian Bagger

Dual Plugged Heads

Back when I did my econo rebuild back in '90/'91, I slightly lowered the compression with thicker base baskets. Seems that that was the recommended procedure then, the changing of the gas to less octane may have been one of the resons that I did it. Any way, I couldn't feel any less performance in the bike. When I put the engine together this time I installed the original oem gasket to get back to the 9.0:1 compression ratio. I dual plugged the head to get a better burn in the cumbustion chamber. I've never had or rode a bike with this setup. But several of the guys whose heads I did where I added the 2nd plug said their bikes really ran good. I guess I'll find out for myself when the engine is installed and I ride the bike. I want a good running bike, but I also want a bike with the right look. I allways thought the dual plugged airheads had that cool look.
 
Timesert lower plug hole

I went with the small plug in doing the 2nd plug. Even so, there is still just a small amount of material in that area and there arn't alot of threads holding the plug in place. I installed a timesert to support the plug. I know at times I'm hamfisted and I didn't want to pull the plug out just tightening it up to much. This eliminates that problem. In the pic with no plug you see the dark round area around the threaded hole. That is the timesert.
 
Drive Coupling Wear

Most of the airhead guys know what this is, but those of you not familiar with the old airheads this is the drive coupling from the rear wheel. This mates to the drive coupling in the final drive. After many miles of service this is the result. Applying antiseize paste or something similar is what keeps this to a minimum. But, after miles of service this will be the result.
 
New coupling

This pic shows the new coupling with the new splines in the hub. Thought I should show the before and after. The grunt work continues. To have a really nice bike there are a lot of details that have to be addressed. The bike has to be gottin into good running condition before the bling stuff happens.
 
Icestorm boredom

Were iced in here, got bored and uploaded some pics off the other site. Just some pics of a head I did years ago. These are off a parts bike R90. Just straight work on a head nothing out of the ordinary. I did probably 100's maybe 1000's of heads. BMW motorcycle, auto, Mercedes, Audi, Porsche, Rover, others. Hemi, Single overhead cam, Twin cam, inline 4 cylinder, 6 cylinder, V8s, probably others I don't remember. Enjoyed doing head work. As cars go, I think I enjoyed Porsche 911's the most. Both stock and racing. A lot of Porsche heads I did won alot of races. Their a lot like BMW heads on the old airheads, I guess that's why I like them.
 
Barry- Nice, very nice.

What looks like a nice aftermarket oil cooler/sump extender, and if I'm not mistaken, the ribs mark that as a post 1977 nosecone?

I'm interested in how the 'tractor' style seat turns out. the stock seat makes my ass hurt after a hundred miles. Might be the 40 year old foam, might be the shape. anyhow, let me know how it turns out.
 
Thx, Rougue; I pulled it off. The # on the back was 1 259 468.9 . The parts book shows 259 469 Who knows for sure. I did see a '73 stamp. This bike was built in late '73. The Breil oil was on the bike when I bought it back in '88. I see it mostly as a conversation piece. One thing I do like is it makes the engine look larger. A minus to having one is the stock center stand usually has to have the cross member sectioned out and moved, rewelded, then painted . The cross member hits the add on oil cooler when it moves from deployed to retracted. I find BMW's to be an exact build. Add on parts generally interfere with something.
 
CBB Slow Goin

Kinda fell behind on working on the build. Bad weather, work, family issues are some of the reasons. Just got back from a freight run over to Mena, Ar.. The Ouchita Mountains are absolutely fanastic. The R90 I'm working on has carried me on many trips over these mountains over 20 years ago back in the day. I was working on the rear wheel and decided I needed a better rim. Thought about finding a used one, got to thinking it would probably be worse than the one I had. Called local and then all over the country. Seems like $400 was the going price. Ouch! Called Grassroots up in Cape Girardeau. They beat everybody on price. I've gotta a buddy who helps them out on special projects, he generally runs by my house about once a week, so he'll drop it off to me. No shipping charges and that will help. Hope to get it in a week or so. Now back to strippen the frame.
 
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