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1986 BMW K75C - Barn find!

D

davekuhn

Guest
Hi everyone!

I just found my first motorcycle. It was in a barn in storage since it was last on the road in 2004. What would you guys suggest I do to it before I try and start it?
I'm going to; Drain the gas (From the tank and..?)
New Plugs (What Kind)
New Battery (What Kind)
Grease the splines for the final drive

Anything else I should do?

Heres a picture of it!
 

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Thanks Bob!

I picked it up for $500. It's got 47k on it, do you guys think thats a good deal?
 
post # 4 in BigBob's linked thread contains critical info. do not attempt a start without replacing the damper. annoying /expensive if you fail to address it first.
 
Sounds like a good deal, did it "run when parked"?

If you get sick of messing with it, send me a pm and I will come take it off your hands, and save you all that trouble.
( looks good, nice deal)
Brian
 
Good price??

Not sure why don't you clean it up and post some more pictures???:dance


Want to get an idea of how the paint is hard to tell covered with dust and other Barn inhabitent's droppings!!:lurk

THANKS!!!!!
 
I agree, clean-er up and more pics. Though, the roundel looks totally un-yellowed, so I am guessing the red has not faded much.....:lurk
 
I think at $500 you were taken to the cleaners. Just because I'm in a good mood I'll help you recover from this financial catastrophe and take it off your hands for $600. :whistle
 
Do not be surprised to find a stuck fuel pump and clogged injectors. It doesn't always happen with prolonged storage but usually does.

I would remove the fuel pump and get it to soaking in a mix of good gas with a strong dose of carburetor cleaner. Give it several days and then try to run it. Reversing the polarity of the connections would reverse the direction of rotation. Sometimes they will break free with a back and forth motion.

Caution: that is flamable fuel in it. Make connections to the pump and then connect to the battery several feet away so if there are sparks they won't ignite anything.

Remove the injectors, Get new O ring seals. Take to a good shop for cleaning and testing.
 
Ok, so I finaly had a little bit of time to look at it (and I mean little - under 2 hours) and by the looks of it, the gas was drained before it was put away. It was running before the guy put it away (Served some time in Afghanistan)

I started to wash it, Still lots I want to do, but it's to find the time. I am going to order a new battery for it, and I will drain the tiny bit of gas from the tank, throw new stuff in and see what happens when I turn the key (Not turning it over) just to see the if the EFI System will engage.

Then if I'm golden still, put the bike in 2nd gear and roll it around to see if the pistons will move freely.

If I'm still golden, then I'll lube the splines, check everything else and get it ready for the road :burnout

Am I on the right track? I'm talking to a friend of mine who owns a couple, raced a couple more of them in the Vintage Sidecar races, and currently has 2 customers' bikes apart in his shop..

Heres the only other pic I have.. Ill get more when I get a chance to really clean it..
 

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I would STRONGLY suggest that the FIRST thing that you do is remove the fuel pump and filter.

Bench test the pump (dry) to make sure it runs. Check the inlet screen. Replace if needed.

REPLACE the fuel filter. Lightly blow through the old one to see if there is ANY resistance, but you should still replace with a new one.

Inspect the black rubber vibration damper that holds the pump. Replace if it appears to be deteriorating.

Inspect fuel lines inside the tank for cracks or softening Replace as needed.

THOROUGHLY inspect the inside of the tank for any crud. Clean as necessary.

If any black or brown gooey stuff (dissolving fuel pump vibration damper) was found in the well where the pump goes AND the filter had resistance when you blew through it, you might want to have the injectors and fuel rail cleaned. If the filter had almost no resistance, you probably could get by without cleaning the injectors.

Visually inspect the inside seams (bottom left and right) of the tank for corrosion. Should be shinny aluminum. If not, could have pinhole leaks. Pour 1/2 gallon of new gas into tank. Feel for any dampness on outside along the lower seams. Let it sit and come back the next day and check again.


Install pump and new filter back in tank.
Put in another 1/2 gallon of fuel.

NEW battery.

Turn on Key and kill switch. Put in neutral. Tap starter and release. Should hear fuel pump run for about 2 seconds. Tap starter again. Pump should run again for a couple seconds.

Set fast idle lever (choke) to 1st click. Start the bike.

DO NOT LET IT RUN LONGER THAN 2 MINUTES!!



Now, if it started, you need to check the cooling system. Otherwise you could overheat the motor and do major damage.

You need to check the coolant level AT THE RADIATOR CAP under the right front of the fuel tank. Should be full to the base of the cap. You need to slide the fuel tank back to access it.

Make SURE the small hose from the filler to the overflow bottle does not have any cracks in it. Otherwise air will be sucked into the radiator. Fill overflow bottle 1/2 full.

Reach in and see if the fan spins freely. It could be seized or stiff which will burn it up.


If all is good with the cooling system, fire it up. The fan should kick on after about 10 min. of idling. If not, could be a problem.


Let us know how it goes.


You should consider putting where you live in your profile. Then people who live near you can volunteer to help.




:dance:dance:dance
 
Thanks so much 98lee, I really appreciate it!

When I get a chance to check some of the stuff on the list I'll report back here with my findings

And i'll update my profile too :evil
 
Something 98lee said kind of concerns my about my bike. Had it for almost a year and never have heard the fan come on. Is that possible? The gauge seems to work and the fan turns free. IF I let it idle for ten minutes, it will get up to the red marks but I can't stand to see it that high and always cut it off. Riding it will never get it over a quarter or a third from the bottom.

OK back on the thread; I envy you. man. I have always thought a bike project would be cool. That is a nice one and I hope you have smooth sailing.
 
Something 98lee said kind of concerns my about my bike. Had it for almost a year and never have heard the fan come on. Is that possible? The gauge seems to work and the fan turns free. IF I let it idle for ten minutes, it will get up to the red marks but I can't stand to see it that high and always cut it off. Riding it will never get it over a quarter or a third from the bottom.

OK back on the thread; I envy you. man. I have always thought a bike project would be cool. That is a nice one and I hope you have smooth sailing.

that's not good. fan should kick on by the time it reaches red. and pretty much anytime you're riding in slow & go type traffic. even city stuff below 40 would usually get things going. That's on 2 K75s & a K11RS, never had a K100, but I strongly suspect it would be the same.
 
that's not good. fan should kick on by the time it reaches red. and pretty much anytime you're riding in slow & go type traffic. even city stuff below 40 would usually get things going. That's on 2 K75s & a K11RS, never had a K100, but I strongly suspect it would be the same.

On a K75 the fan almost never comes on (that's why they fail more often).


K100s and k11s are a different story.



:dance:dance:dance
 
That's a very good looking bike. It's peculiar how the fly screen is painted the same color as the bike. Perhaps the entire bike was repainted at some point?

After you get the engine sorted out, I would put new tires on.
 
On a K75 the fan almost never comes on (that's why they fail more often).

True. That is why I was quite surprised when my fan failed. The bike was 15 years old at the time, and probably only had 2 hours of run time on the fan. But they spin in the wind and that still wears out the brushes.
 
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