Living with an old BMW Boxer? (R100RT etc)

[ph9]

You used to see a load of these around, but I think I only saw one on the road this year.

I'm semi-interested in an early 1980's bike - maybe an R100 or R80.

Are all parts still available?

Are they still up to being used as an everyday ride?

Is corrosion a major issue?

At what sort of mileage do they give up, or is it possible to take them to the moon and back with just regular servicing?

Once used to it, are they a decent ride - eg stable on A-roads, and decent handling on B-roads, and adequate performance?

[srob]

My dad had an R80RT as our only transport when I was a kid. We went all over the place on it and it was comfy and he maintains it was the best fairing he’s ever known!

Only thing I can remember him doing was something to do with the shaft drive (maybe a seal?) and normal routine maintenance.

I’d happily have one, I actually called about an R100RS when I was selling the Bimota to see if the bloke wanted a swap. He informed me I was about 50th in the queue for it so probably not

[black-k1]

I have a 1984 R100CS and love it. Easily quick enough to keep ahead of traffic, all day comfortable, loads of character, simple to work on and all parts available.

[Merch131]

Had a 79 R100S.. bought it at 80,000 miles, sold it at 190,000 miles.. ran fine with just regular servicing. Spare parts are easy to find, from the likes of Motorworks and Moto Bins. Handling was ok, but at higher speeds it would weave a bit, I never pushed it too hard. Worse part of the bike was the brakes.. weak and wooden. The later models got better brakes, Brembo I think.

I'd have another, though I'd have to upgrade the brakes, suspension. Sadly prices have gone up a lot, as they are wanted to be converted into cafe racers or scramblers.

[ph9]

It sounds like it might be right up my street.

I tend to keep vehicles, and like to put higher mileages on them, so would be okay with spending a bit of money to upgrade suspension wtc when required.

[TT1138]

Dad has owned an 1979 R65 and an 1993 (one of the last) R100RTs. Great bikes. Not fast, and handling isn’t up to much by modern standards but very nicely built, easy to work on and easy to ride compared to some classic bikes.

The RT was much more modern, and had the twin disk Brembo-branded front brakes and mono lever. The R65 obviously a lot older and lower powered. Front brakes were interesting.

Old boxer BMWs are probably one of the best classics to own. Parts still relatively easy to come by, Motorworks are excellent, and there is an absolute wealth of knowledge online. Only downside is the vast numbers that have been chopped into crappy scramblers, bobbers and customs. Finding a good original condition bike is a lot harder than it was 10 years ago.

If you find an immaculate R80 or R100GS in your search with low miles, fully serviced and in original condition for £2k, don’t buy it. Just send the details my way and I’ll remove the temptation

[Rubin215]

Since BMW have been making boxer engined bikes since the early 1920's, I don't think you can really class an 80's model as "old..."


That having been said, on the 70's and 80's ones the brakes are rubbish, the suspension is either far too hard or far too soft depending how worn out it is and the gearbox is positively agricultural.

Engines are round-the-world reliable as long as you keep changing the oil, fairings are nicely protective, seating position is comfy enough to do a full tank at a time.

Personally, I would look for a 90's onwards model.

[black-k1]

Assuming you are looking at a R100, then here's a brief overview of the changes and things to note.

1976 to 1981 - Good performance and reasonable handling for their day. Winners of many endurance races. RS is worlds first wind tunnel developed fairing on a production road bike.
engines 60bhp or 70 bhp - depends on model and option box ticked when new. "Heavy" flywheel. (Relative to later engines.) Round air filter. Mechanical points.
Brakes twin disk (crap) or single disk (really crap) depends on model - ATE floating calipers - at right angle to forks - and drum rear on most models. Disk on some but disk is no better than drum.

1981 to 1984 Acceptable performance and handling for their day.
Engines 70bhp. Lighter flywheel, flat air filter, Electronic ignition.
Brakes twin disk (Just about OK) - Brembo calipers - attached to fork leg - mix of drum or disk rear.

Weaker points on both: Coils/HT leads. Alternator rotor windings. Rear main seal - leads to clutch failure (dry clutch). Gearbox is solid but very agricultural - don't forget to change the (separate gearbox) oil. Note though that by "weaker" I mean tend to fail after about 35k to 40k miles. Rocker spacers tend to need replacing at around 60k miles.

Good and easy to install upgrades: Stainless steel exhaust, braided brake lines, progressive fork springs (with preload spacers sized to suit) and slightly heavier fork oil, replacement rear shocks from ... just about anywhere!

1986 - 199? Solid and reliable but totally outclassed in it's day and, IMHO, has lost much of the character from the earlier bikes. Launched to stop the moaning from the beards in cardigans!
60bhp engine (different to previous engine),brembo brakes, mono-shock rear.

Like all shaft drive bikes pre-1990, they all suffer from shaft jack. If you've never experienced it, you'll feel the rear "jack up" as you let the clutch out to pull away. Just something different to get used to. The only "down side" is that the opposite happens if you shut the throttle abruptly, the rear squats. That's the last thing you want to happen when you find your coming into a corner too hot as it causes the front to push wide! Ride one properly - slow in, fast out, and, with their low down torque, they can make surprisingly brisk but relaxed progress for old ladies.

[Krikkit]

Fantastic info there K1

[ph9]

Thanks very much!

What's better about the 1990 and later bikes - is it mainly the monoshock rear suspension?

As you say, it looks like a number have been converted to scarmblers and cafe racers, and prices seem quite high. I suspect that finding a low mileage mint one for £2000 might take some time!

[black-k1]

ph9 said:

Thanks very much!

What's better about the 1990 and later bikes - is it mainly the monoshock rear suspension?

As you say, it looks like a number have been converted to scarmblers and cafe racers, and prices seem quite high. I suspect that finding a low mileage mint one for £2000 might take some time!

The model run from 1986 to about 1996 were pretty much all the same basic bike but with different plastic on. (RS, RT, GS, Mystic etc.) Any "improvement " in that time period was minor and limited to small tweaks. The best thing to come out of those bikes were the first GSs. That was when a GS was a physically small (for engine size) bike that could cover huge daily mileages and was manageable on dirt tracks, dessert roads etc. without the requirement for the rider to be a Dakar Rally contender to ride it or be built like Mr Universe to pick it up. If I was going around the world now, a '90s air cooled GS would still be top of my list of bikes to choose for the journey.

Note that the R1100 and later bikes were a completely different concept with everything new. The only similarity with the original bikes was the engine layout. The R100 range of air cooled twins can genuinely trace it's development back to pre-war bikes and BMW turning a Douglas engine through 90 degrees.

So many of the "proper" air cooled twins have now been butchered to make hipster scramblers and cafe racers it's a real tragedy. It does mean that I'd suggest you have virtually no chance of getting a reasonably unmolested bike for anything like £2000. The only good news is that if/when you get a decent unmolested bike, whatever the price, it's unlikely to lose any money.

[Pat H]

black-k1 said:

Lots of good stuff.

I have owned the following:

1977 R100RS
1981 R100
1986 R80
1993 R100R

Look out for slipping clutch. My 1981 suffered from crank main seal failure at 50,000 miles, which contaminated the clutch. As you can see, it's a big job, albeit not a mechanically complicated one. Also expect leaking pushrod seals.





Otherwise, my 1981 R100 has been very reliable. I have just done a top end rebuild and there was no visible wear to the cam, the tappets or the bores.

It's easy to work on and spares are freely available, though not always cheap. It has as much character as an old British twin, but still makes a capable touring bike. The original Krauser luggage is excellent.

Also worth a look are the later R65s, in particular the quirky R65LS factory cafe racer. An R80ST is a very nice thing, if you can find one.

These are the one's I've known:

1977 R100RS with big fairing, spokey wheels, crap brakes, heavy flywheel, aluminium airbox and clockwork ignition. A big, heavy, horse of a bike which I couldn't get on with.



1981 R100 with R90S cockpit fairing, cast wheels, proper brakes, light flywheel, plastic airbox, heated grips and leccy ignition.



1986 R80 Mono. Single disc not up to the job. Most have two. Lost the classic twin shock good looks, but miles better ride and far more comfortable. 800cc motor revs harder and is smoother than the 1000. Best for daily us. Cheaper than the twin shock bikes, which are sought after by the cafe racer and street scrambler brigade.



1993 R100R. Big forks, big brakes, wonky styling. An unhappy compromise. Modern bike with ancient engine and box, no classic charm.



Too many air cooled BMWs have been turned into street scramblers or cafe racers, often very badly. A standard bike with a few sensible upgrades is the way to go, in my view.

I still have the 1981 R100. It looks original, but has progressive springs, braided hoses, 95mm high comp pistons, gas flowed heads, standard looking straight through silencers and a breather that doesn't vent back into the carbs.

Best for daily use would be an R80 Mono. If you want a classic twin shock, then anything post 1981.