Looking at a 1980 R80

[Larry Fine]

The R80's are a bit slow though smoother than the R100. The R100's have good mid range punch and work surprisingly well on mountain roads with a wide powerband. I liked the airheads I used to own. So simple to work on too.

One of my best friends has an '88 R100RT. He really likes it.

If I had a BMW, the FIRST thing I would do is flip the kick-stand spring to the latching position.

 

[dduelin]

Thanks for the info...unfortunately the original owner is 92 and not long for this world... not sure what info and receipts are available or can be easily located...

Well, with the miles on it the soft original valve seats have likely been replaced by now. Can you start it or at least get a cold compression check? There might be a set of panniers somewhere in the garage to fit on the pannier mounts.

The R80's are a bit slow though smoother than the R100. The R100's have good mid range punch and work surprisingly well on mountain roads with a wide powerband. I liked the airheads I used to own. So simple to work on too.
I wish that the more modern bikes were so easy to work on. I love my Africa Twin but it is a nightmare to get to air filters, sparkplugs and to check valve clearances. Probably as difficult or maybe more than the ST's. Luckily you don't have to do much to maintain them though. The only modern bikes that seem to be easy to service are the Motoguzzi's.

I really liked my R100. It had a nice soft power delivery and a pleasant gait going down the road. It redlined at 7200 rpm but going above about 6000 wasn't necessary for (semi) rapid progress. I dyno'd it once and it produced about 54 rwhp if I recall correctly. In 1981 BMW claimed 70 at 7000 rpm at the crank. An interesting footnote was in the back of the owners manual. IIRC it gave the engine's rated hp output at "maximum continuous horsepower rating at 7200 rpm" similar to aircraft owners manuals. BMW was confident it could run long periods of time at redline. Though the engine design couldn't be more different I am fond of saying the NC700/750X is the modern airhead. It has 46-54 rwhp depending on model and with its 270 degree crank it delivers a nice soft power delivery being torquey in the low and mid range and redlines at 6500 rpm. Going down the road it has a pleasant galloping gait, soft pulsing vibrations, and clear mirrors. The valves are screw and tappet and easily accessed with the laid-down cylinders. Maintenance needs are easily done.

 

[kerbside]

If well maintained they are good bikes. This one I see has a nice Avon aftermarket fairing fitted.
The 100 series I think is nicer to ride with the extra power, but if you want a pleasant cruiser that also handles go for it.
Interestingly I cannot now ride my 100 for long in the summer with the fairing lowers on - just too hot even with boots on.
Apart from splines I'd make sure the exhaust nuts can be removed ( with the bmw wrench) and the front caliper moves freely.
They have as std a stupid self retracting side stand that can be replaced by an aftermarket unit if you can find one.
My '84 100rt has 140k miles and is still untouched. Wonderful engines.

 

[Larry Fine]

They have as std a stupid self retracting side stand that can be replaced by an aftermarket unit if you can find one.

As I mentioned above, the spring upper anchor point can be rotated without any new parts.

How to change the flip-up feature to stay down
1. Put the bike on the center stand.
2. Loosen the left side front motor mount nut, 19 mm.
3. Flip the stand into the down position, while watching the plate, at the motor mount bolt, holding the spring.
4. It should have rotated slightly.
5. Tighten the motor mount nut.
6. It should now be a stay down type.

 

[kerbside]

As I mentioned above, the spring upper anchor point can be rotated without any new parts.

As always you live and learn - wish I'd known that in the early 80's !

 

[The Forester]

Just to chuck a large spanner in the spokes. I'm riding a 1994 K1100LT which currently has just under 80K on the clock. She's a 1 owner bike that had been stored for just under 10 years when I bought her. A quick clean out of the fuel tank, some fresh fuel and an oil n filter change along with a new battery and after following advise from Chris Harris on You Tube by putting a bit of oil down each cylinder and away she went, smoked a bit for about 10 minutes but that soon cleared and no problems since. She runs as sweet as any newer jap bike. In fact I has an ST1100 just before we moved over here to Tunisia so had to make a hard choice, and given "she who must be obeyed" liked the comfort of the K over the "play" value of the ST and the fact we were going to have to do about 1500 miles just to catch the ferry from Genoa to Tunis the ST was sold. We've just returned from 12 days in Italy where we did nearly 2K with absolutely no problems at all.
John