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Godfather
10-03-2009, 10:23 PM
In my ongoing search for the deal of the century, a friend of a friend told me about a BMW he knows of so I looked at the 75' R75/6 today. The first impression was..."I drove 2 hours to look at this thing? Man It looks rough!" Rusted handlebars, broken adjusting knob, rust on some of the spokes, many small rust spots on the white tank, some rust and pitting on the exhaust system, but oddly enough not the exhaust nuts. The aftermarket seat is ripped. The frame has some surface rust spots. Side covers are missing, no fork boots. Front turn signals, but not the shiny chrome stems, are missing. all rubber bits look really weathered. The engine is ozidized badly. Most all nuts and bolts have rust on them...they must not be stainless eh? Tires were holding air, but must be replaced.

I walk and crawl all around it looking it over and over. I touched, tapped on and squeezed the exhausts checking for holes rotted through them, but they are solid. I do not see any evidence of oil leaks, and it is obvious the engine has not been degreased or washed. Hmmm, interesting. The owner states he had the carbs rebuilt and he replaced fuel lines and battery too. I look in the tank, no rust, in fact it is sparkling clean. The engine oil is clean and he said he did not change it. He explained he aquired this bike as part of a car purchase deal. He has no interest in restoring it. so he is selling it.

I ask if it runs...Without saying a word... he opens the fuel petcocks, adjusts the choke, turns the key, hits the starter button and the R75 instantly comes to life! This thing sounds amazing! Idling smoothly within 2 seconds of him returning the choke back to it's original position, and it keeps on purring, quietly, smoothly as if to say, DONT JUDGE A BOOK BY IT"S COVER. BTW there is no sign of any smoke.The throttle does not return/spring back easily, I inagine the cables are to blame, after all this bike has been sitting for a long long time. The ODO reads 2994miles and it works??? The tach squeals so he disconnected the cable. The brakes work. the indicator lights Gen and neuteral are lit. With a slight increase in rpm the gen light goes out. I ask to ride it and get the go ahead. The trans shifts into first gear on the second attempt and I am off...very slowly through 1st. I take my time shifting into 2nd because of the throttle, a minor clunk and all is good, the shift to 3rd is smoother. I never got to 4th or 5th because it was just not safe. All the while the bike is just purring along. I go only about 2 blocks total.
He is asking $1800 and is pretty firm on the price. Is it possible the mileage is original and this thing sat for 30+ years? It needs $1000 in parts not counting seat, shocks, or anything electrical. That is just to get it on the road and nothing done cosmetically.

What are your thoughts?

As allways, THANKS!

AnnapolisAirhead
10-03-2009, 11:17 PM
Sounds like it could be brought up to the point of a good daily rider. $1800 isn't too bad, especially if you are a wrench, but I wouldn't hold your breath that a bike that's been sitting for so long is just going to need tires and gas. It's a nice bike, but the more sought after R75 is the /5 IMO. With the /6, BMW introduced the R90/6. Some will say that the 750 is one of the best balanced engines, seems to carry over to the K75 bikes as well--don't know, I've never had either. Hard to go wrong with $1800 though--for a running Airhead.

The mileage verification is damned near impossible to determine (could have been a disconnected speedo cable, or could be the real deal). In either case, expect lots of rubber bit replacements, electrical going through, etc. It could be really low mileage and look rough from simply sitting outside, unloved for years. That'll just make bringing her back to usefulness a bit harder but the innards would be in pretty good shape after a couple fluid changes. Seals (forks, rear main, etc.) will be bad most likely. I'd pull the oilpan and the oil filter (cut it open) and look for any metal flakes. Probably won't be any.

The exhaust nuts are aluminum and not the same composition as the heads so probably not going to pit significantly. The nuts and bolts on the bike are not stainless.

What is likely robbing the bike of any power is the valve and points adjustments, and the carb synchronization. Fuel delivery would be another thing to resolve immediately--petcock screens, petcock rebuilds possibly and definitely the fuel line (it's too cheap to NOT do that).

Things to look for:

Steering head bearings
Shifting (especially downshifting)
Starter relay
Splines (rear wheel and transmission input)
any metal fragments on the oil drain plug

There are probably other things too, but that's a great way to get to know the bike.

20774
10-04-2009, 05:29 AM
Look at the footpegs and rear brake lever. If it only has 3K miles, the foot pegs should look essentially brand new and the brake lever should have all of the raised points on it. Those are items that might some indication as to actual mileage....assuming they are the original parts.

Bill Burke
10-04-2009, 05:58 AM
There is basically nothing in your description of the bike that suggests to me that it's a 3K mile barn find. Sounds more like a 103K mile bike to me. To "restore" a machine as you've described is more likely going to cost at least $3K and lots of hours. A bike in the condition you've described will need a "top to bottom" rehab effort which, unless you have nothing better to do and plenty of spare change, will take at least a full year and probably closer to two. It sounds more like a $1k collection of parts than an $1800 potential rider to me. These bikes can be brought back, and should be, but it's unwise to underestimate the effort and cost involved to get all components back to a fundamentally sound, reliable point. That's my opinion, as harsh as it may sound.

For a superb dose of reality, read this thread from start to finish:

http://www.bmwmoa.org/forum/showthread.php?t=30074

Godfather
10-04-2009, 07:35 AM
All of this input is VERY VALUABLE INFORMATION and I thank you. The one thing that gave me a good feeling is that the bike fired right up and ran so smoothly, but after all, it is an "airhead" and they are suppose to do that.

Thanks again.

Godfather
10-04-2009, 09:54 AM
"for a superb dose of reality, read this thread from start to finish"
http://www.bmwmoa.org/forum/showthread.php?t=30074[/quote]

doh!!! thanks Bill

crazydrummerdude
10-04-2009, 10:49 AM
"for a superb dose of reality, read this thread from start to finish"
http://www.bmwmoa.org/forum/showthread.php?t=30074

For what it's worth, my R90 is now a daily driver. The problems I am encountering now could really happen to anyone.

I rode it to the MOA rally this year, about 1700 miles round trip, "at speed."

http://img.photobucket.com/albums/v469/aretnap69/bmw_r90/20090719001.jpg

I have $3500 in it. There is little else that needs replacing. Does anyone else have that little in their airhead with new rings, honed cylinders, cleaned pistons, new valves, new valve springs, fresh valve seats bead blasted heads, rebuilt transmission with new gaskets output shaft and new bearings, new steering head bearings and races, rebuilt carbs, rebuilt master cylinder with new piston and seals, rebuilt caliper with new piston and seals, new fork seals, new fork boots, new fork oil change, new engine oil change, new everything else oil change, reworked the headlight wiring harness, reworked the turn signal wiring harness, new bulbs, new points, adjusted the valves, balanced the carbs, new air filter, new oil filter, new tires, different brake rotor, new rear main seal, new oil pump o-ring, new clutch diaphragm spring, new throttle cables, new brake pads, and a new transmission boot? I kind of doubt it.

I think the fact that your potential bike runs and shifts makes it relatively valuable (although not the "deal of the century").. but I'd of course try to haggle on the price because of the appearance. If you end up biting the bullet, start a thread like mine!

Godfather
10-04-2009, 11:37 AM
Although I an somewhat mechanically inclined, my home shop (read garage) is limited to basic tools and my knowledge of airheads is non existant. I know you gain knowledge and experience by doing, but this may be a bit much for me...that is...more financially, than ability. I an going to make what I believe to be a reasonable offer and see what happens.

Thanks again.

paulfinney2
10-04-2009, 10:11 PM
I bought a 76 R75/6 that had sat outside under a tarp for 4 years. Everything soft had to be repladed, but the bike was mechanically in good shape, not cosmetically. I spent probably less than $800, and have a great running and riding bike now. It's not a show bike, but it loves to start and run. I consider it a keeper.

fabiox
10-05-2009, 12:01 AM
all airheads must to be restored ! no one should be left behind:beer:clap

rpeckham136133
10-05-2009, 11:11 AM
If you need encouragement.... I bought this:
http://bpeckm.smugmug.com/photos/421596219_xiD8i-M.jpg


Which, after "some work" (see thread link below, if you dare...!) turned into this:
http://bpeckm.smugmug.com/photos/663676825_FWK9G-M.jpg


:heart
I'm a happy camper.....