Vintage Beemers comparison

Got a question about comparing the various pre-/5 BMW's.

I'm in the market for a vintage BMW to ride (not a garage queen), and am studying the various models. What would your assessment be of a 50/2 versus a 60/2 versus a R69S? Aside from the obvious, what are the performance differences? I want a bike for a vintage touring experience. No racing or high speed riding. However, being this is the 21st Century, you need to share the road with modern traffic, so sometimes you need to get up to 65 mph, sometimes you need to pass a slow moving farm vehicle, sometimes you need to get up a hill without bogging down and holding up traffic. Would any model be capable of this kind of riding or should I look for an R69S to get the most bang for the buck?

And how about reliability? Assuming the engine is in good shape and the slingers have been cleaned, etc. is any one model more or less reliable if not pushed too hard?

Thanks for the advice.

--Scott
Troy, NY

My opinion is that the R50/2 is probably not going to give you what you want...HP was only 26. It would just take a bit more to get up to speed.

The R60/2 or R69S is probably more the ticket. The R60/2 had 30 HP while the R69S had 42 HP. The R69S is more sporty but has high compression pistons, so it will probably take high test gas. Timing is a bit critical...with the higher compression, if the bike has a tendency to ping, it might blow a hole in the piston. The R60/2 might be a middle of the road bike, able to cruise at a reasonable speeds and has a little more low end grunt...typically people use the R60/2 to pull a sidecar with the correct rear end ratio. Of course, with the proper rear end ratio, the R60/2 can be a good travel vehicle as well.

These bikes came stock with 6v electrics and a magneto ignition, so don't expect to power a lot of accessories. They're not too complex, but you better be ready to fix them from time to time. You can convert to 12v and run better lights front and rear for visibility. Realibility-wise, they're about the same, but the R69S is a bit picky with the higher HP engine.

Brakes are OK for the era, but not at all like today's brakes. When out on one of these things you have to think a bit more defensively and realize you don't have the punch to get out of the way...you have to plan further ahead.

I really like the R69S with the Earles front end...it's such a different ride than my /7. I just completed a 3700 mile trip on my /7...I'm not quite comfortable yet to do that with my /2. Maybe one of these days...

This might be better under the Vintage forum.

I often do touring to rallys up to 1000 mi round trip on all
three of these bikes - rural 2lane preferred 70mph max
60 best

You did not state your weight or size - a big man on an
R50 plugging into a headwind will kill the bike

My 2 R69S bikes now down with holed pistons trying to
push too hard on long hot interstate sections will become
conversion bikes in the near future

My favorite is R60 - once rode one of these all over Mexico
without problems - flatter torque curve and less compression
is easier to ride and less prone to piston problems

I have one R60 with aftermarket 12v alternator which works
well - I have another R60 onto which I cobbled a /5 alternator
which also works well

There are modern brake shoe materials which have more grab

Even the stock brakes are quite effective - the problem most
have is that they learned on disks and simply cannot apply
enough lever force to get necessary effect - given enough
squeeze one can lock the front wheel on dry pavement

You need to tour alone - if you try to run with the modern
bikes you will kill your /2 trying to keep up

An alternative is a pre /5 motorcycle updated with a post 1969 engine and transmission, known as a /2 conversion, A well executed conversion offers the classic styling and ride experience of a vintage BMW and the advantage of technical improvements / reduced maintenance costs of the later type engines. Although most conversions are fitted with larger 750cc - 1000cc engines for sidecar use, a 40hp 600c R60/5, R60/6, or R60/7 engine works just fine for solo use.

R60US: THAT is a beautiful bike. My compliments if it's yours.

Bill Burke said:

R60US: THAT is a beautiful bike. My compliments if it's yours.

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I wish!

It's on the Epco (stainless exhausts) site and I believe it belongs to Tom of Epco.

r60us said:

I wish!

It's on the Epco (stainless exhausts) site and I believe it belongs to Tom of Epco.

Click to expand...

The /2 conversion seems to come close to my idea of perfection. Sort of an airhead version of the automotive Shelby Cobra (upgrading the internals while preserving the classic superstructure).

20774, Kurt, how would you comapre your '78 R100/7 to the R80/7 same year. My R80 is my favorite bike to ride,never ridden an R100,but I'm thinking of getting one.Will I notice much of a difference? I don't do alot of long distance touring.
George

georgej said:

20774, Kurt, how would you comapre your '78 R100/7 to the R80/7 same year. My R80 is my favorite bike to ride,never ridden an R100,but I'm thinking of getting one.Will I notice much of a difference? I don't do alot of long distance touring.

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George -

I wouldn't know as I've only been on my two bikes. I've heard the R80 should be smoother, all things considered. On the performance end, some will depend on the rear end. My /7 has a 3.0 rear end, so it's kind of meant for touring. My guess is your R80 has got a 3.2 or 3.36 rear end. That will make for peppier starts but create more RPM for the same highway cruising speed. If you're just doing local riding, the R80/7 is probably well suited for that. Touring would likely be better on a 1000cc bike, especially if 2-up.

I'm not a small guy (225lbs.) and find both my R60/2 and even my R51/3 (24hp 500cc) adequate for touring. Both will do 75+ on the freeway all day. Acceleration to the top end is pretty slow, and drum brakes are not going to stop you like even /6 disks, let alone modern brakes, but with the modern lining material that Vech sells, they are passable with careful riding.

However, being this is the 21st Century, you need to share the road with modern traffic, so sometimes you need to get up to 65 mph, sometimes you need to pass a slow moving farm vehicle, sometimes you need to get up a hill without bogging down and holding up traffic. Would any model be capable of this kind of riding or should I look for an R69S to get the most bang for the buck?

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Any of these bikes will get up a hill. You'll have to choose the right gear, you may not be able to hold 4th going into a headwind uphill. Passing a farm vehicle is no problem, but you'll be more constrained about passing someone on a highway who is doing 50 and you want to do 60.

The thing about riding these older bikes is that it requires you to be more involved with what the bike needs. Modern bikes have so much power and braking that you can just do as you please. These bikes need you to consider their needs as well. Listen to the engine, is it telling you that it's lugging? You may have to run at a slower speed than you want in 3rd because you can't get into the power band in 4th. It's the nature of these bikes.

And how about reliability? Assuming the engine is in good shape and the slingers have been cleaned, etc. is any one model more or less reliable if not pushed too hard?

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Like all generations of BMWs, these have their quirks and foibles. Generally they are quite reliable, but they have much shorter service intervals (oil changes at 1k miles, service intervals at 3k miles). Because of the magneto ignition, these bikes run even if the rest of the electrics are fried or the battery is dead; there's no connection between the ignition and the charging system. The 60 watt 6V generator means that you can run the headlight, but nothing more. There's a 6v Halogen headlight that does put out more light available.

The two trouble spots that people talk about are the heads on the mid 60s bikes, which are often referred to as "butterheads". The alloy was changed (without BMW's knowledge) and it moves around. The spark plug inserts come out and the rockers gradually sink until you run out of adjustment.

The other thing is that there's no oil filter on these bikes, but the way they oil the crank is with a pair of "slinger rings". These are sheet metal disks with a lip at the outer edge. The lip fills up with centrifuged wear particles and eventually this reduces the oil going to the conrod bearings. This causes the bearings to wear, the motor knocks and at some point it can sieze. Crank repair is expensive because the cranks are pressed up with one piece conrods, and there are very few people who can service them. Better is to pull the motor apart every 40-60k miles and clean/replace the slinger rings, which are cheap.