I am giving up to find out. I have R50/2 with a R60 engine or R69

[mrtnfischer]

I bought a barn find, R50/2 1965 , when I got it back, I noticed that the carbs are a R60, than I got it started (Engine had low miles on the rebuild) WOW, lots of power as I have a R60/2 to compare it too and this has 20% more umph.. Maybe I have a R69 motor.. who KNOWS out there.

So What do I have Engine Number is 634434, the Speedo says 28K and I believe it on the chassis as it is very tight and clean especially all of the chrome and Aluminum..(perfect)
The previous owner new nothign except he was told 8 years ago the engine is rebuilt (not a R50) and the engine is clean, tight and strong. so What engine do I have.

The chassis number is a R50/2 as it is on the tag and the frame. They match but not the engine....
Maybe I have a Special model belong to a famous Kraut from the 60's like Herman Gorings son. Or Steve McQueen??

I tried to find out using the Forum but the sites they send you to really don't work.
Also this bike is light Tan, (not Dover White, as I had a R50/2 that was Dover... with Brown Pin strips,) very nice but I am sure not a factory Job?? Anyone out there know different??

 

[mrtnfischer]

R50/2 Hybrid R60/2 or R 69/2 or R69s I dont know if the post worked.

Gee did the post work

??

 

[dennisdarrow]

I suppose someone will come forth with how to take the numbers off the motor, compare it with the ones stamped on the headstock, take the head off and check to see what size piston you have..........or......

Congratulations on a totally beautiful machine.........RIDE THAT PUPPY...........God bless......Dennis

 

[barryg]

I'm no vintage expert, but. The valve cover is for a R50/60. The head looks to small for a 69S. The air intake tube looks like R50/60. I'm sure the experts will chime in shortly.

 

[20774]

Martin -

Here's at least one website you can check the numbers out:

http://www.bmbikes.co.uk/chassispages/enginechassisto69.htm

Also, go to this website, and type the number into the boxes on the left...it will take you to the page for that specific model:

http://vintagebmw.org/v7/forum

From the number you gave, the engine is an R50/2. As for the carbs, often times, the carbs are interchangeable depending on throat size and all that's different is the internal in terms of jets.

The R50/2 had 26 HP while the R60/2 had 30 HP. If you're noticing significant drop in performance, then maybe the bikes needs a good tune up. I can never remember which is which, but one difference in cylinders between the R50/2 and R60/2 is that on one, the fins come to a point in front and rear of the cylinder.

In the Vintage area of the forum, check out this thread where I've been compiling models, VINS, and year build info:

http://forums.bmwmoa.org/showthread.php?50039-2-VIN-Numbers-Model-Years-and-Build-Dates

You can get a sense of when the bike was actually built.

Hope that helps.

 

[44006]

The picture does not show the exhaust port or the front of the cyl.

Difference at a glance between R60 and R50 is the shape of the cyl

R60 cyl the finned section is not round - have bumps or protrusions front and rear

R50 cyl the finned section is round

Rocker covers look like R50 or R60

Performance of well tuned R50 with 27/8 rear end and 350x18 tires is not all that different up to 65mph
from less than perfect R60 with 25/8 rear end and 400x18 rear tire

something like 26 hp vs 30 hp

I have both R50 and R60 in good tune and the ride on rural highways up to 60-65mph is not too different
The R50 is smoother and shorter stroke so spins up faster than the longer stroke R60

 

[Friedle]

r 50, r 60, or r69s

The R 69 and R 69S both have round cylinders like the R 50, but the R 69/69S heads are longer and more pointed at either end than the 50 or 60. The 69/69S valve covers are also different and won't fit on either the 50 or 60. Carbs are different as are the air tubes. R 69/69S also has a steering dampner under the steering neck. Those are the easiest external visual clues to determine which is which.

Friedle

 

[typ181r90]

A few things:

* Carbs on the R50 and R60 were both 24mm carbs, and while they had different Bing ids, I think that only reflected the difference in jetting. Maybe the PO found R60 carbs and put them on since they're both 24mm, need to check the jetting
* The muffler is definitely incorrect, almost looks like a /5+ muffler was put on
* Valve covers are definitely R50 or R60, the R50S had its own special valve cover that resembled the R69 one
* Air cleaner is choke type (R50/R60)
* You can't really see the exhaust nut, but it kinda looks like it could be the finned type from an R69S, but then again like I mentioned before, the exhaust is wrong so it could just be mismatched parts again
* Besides what was mentioned before, you could also tell the difference between R50 and R60 cylinders by the R50 having 8 cooling fins and the R60 having 9 (see here: http://bmwdean.com/slash2.htm)
* Your engine number is an R50/2 number (1960 — 1969 R50/2 & R50US 630001 — 649 037)

Soooo, definitely appears to be an R50/2 and not an R69 or R69S. Maybe you just have a pretty freshly rebuilt engine and can feel the difference?

 

[mrtnfischer]

R50/2 vs R60/2 thanks, these are great clues

I had a white R50 but it had small carbs and that ran good but was a little slower than the r60

I have a r/60/2, 1962, next to the tan R50/2?? that performs like a R60.

so, I will go out and compare closer, especially the number of fins and the "Pointy shape of the heads"

Thanks every one.

I will get back wit some Pictures.

 

[mrtnfischer]

The R50/2 with Steroids with the R60 jugs



This can give us a closer look at the bike. It is not the Dover white, but a light tan with Brown Pinstripes. Starts first kick and very strong motor, the speedo says 22K and the frame is great and very tight compared to the R60/2 that I have next to it in the Garage with a side car. (88K) Both the R60 and the R50 (R60 clone) have had engines redone.

So, Someone changed it to the R60, Since the R50 was a shorter stroke, they must have put in taller pistons or what?? how day do dat.

So now that I have 2 bikes alike (one has a side car) what should I do, I am thinking of selling one...
any ideas ..

 

[typ181r90]

Heads were the same for the R60 and R50, BUT if they really wanted to convert your R50 to an R60 then it would require different cylinders (which apparently it has), different pistons, different connecting rods (which means different crank pins too), and even different push rods. I'm not saying that you're wrong that your R50/2 engine was converted to an R60/2, but was it converted with all the correct parts? If I were going to be replacing the crankshaft and the rest of the bottom end, I'd likely just replace the whole engine case with everything inside of it. Why would you put everything in another R50 case that doesn't have numbers matching the frame? Just seems very odd.

If you ever get the heads off, take a look at the pistons. You could easily tell the difference between high compression R69S pistons and the lower compression R60 ones. R69S pistons are still the same diameter as R60 ones, even if the stroke is different so technically they could fit in R60 cylinders.

With all the apparent mods done (incl. the exhaust I mentioned before), who knows what's in there? As far as selling one, if you absolutely had to sell one, I'd sell this one. Numbers don't match, possible hodge podge of parts, custom paint. That being said, I would keep everything. This bike to thrash around on and put the miles up on, the other ones to use for special rides while they accumulate value. My R60 project was originally purchased just for the frame to build a conversion bike, but it came with an engine case with correct numbers and a title, I figured I'd build it back to stock and put the miles on my other bikes since the /2 and earlier bikes' prices are getting kind of ridiculous.

 

[mrtnfischer]

R50 to R60?? again

Every thing you said about the conversion side of the R50 to a R60 is of course correct. As far as I can figure, which is not far here is the synopsis as I see it
1. There is the 9 count on the fins, same as my R60 next to it
2. Has the same carbs ( my previous r50/2 had smaller carbs and that was last year in 2014)
3. Seems to have more power than my R60 has.

So I am thinking that they put on the bigger cylinders and just used taller pistons and did not touch the bottom end... But since the numbers are a R50 number set, than they got a engine from another R50./2 (maybe a crack up) all redone and just put it in. Know one know on a barn find as the previous owner was dead.

The last person who told me to sell my last R50 that was restored and the correct color, said, "It was not worth any thing 'cause the numbers did not match on the engine." Was unable to appreciate the value of wanting a good looking, good running classic bike. Profit on the sale was over $6,000

So Here is my other "Incorrect bike, a R11 that has the R12 cylinder heads. So I got 5 points off. They also could not figure out if I had the proper horn?
But what I think, is none of the number stuff really matters. Because all those who care about "Numbers" will probably be the last generation to do so. (PS the Numbers on the R11 don't match, but of course, they didn't.

Here is a picture of the previous r50/2 that had the smaller carbs, what a looker but alas, the wrong number on the engine. ( I think there is a evil BMW troll, that goes around switching numbers) HIS DAYS are numbered. Someday, no one will care when Isis is riding the antiques.

 

[typ181r90]

I think you missed what I meant. I wouldn't sell it, I'd ride the hell out of it. I said if I "had" to sell something, I'd sell that one.

I'm with you, I'd rather be riding, incorrect or not, but as I said, the prices of these old BMWs is getting kinda nuts, that's why I'd keep all the stockers low mileage. Nearly every one of my bikes is custom in one way or another.

 

[mrtnfischer]

Can you put R60 Jugs on a R50 with Taller Pistons?? is there a kit, Curious

I think you missed what I meant. I wouldn't sell it, I'd ride the hell out of it. I said if I "had" to sell something, I'd sell that one.

I'm with you, I'd rather be riding, incorrect or not, but as I said, the prices of these old BMWs is getting kinda nuts, that's why I'd keep all the stockers low mileage. Nearly every one of my bikes is custom in one way or another.

I have often wondered why the fuss on the numbers. My Neighbor here in Pa is into Big Block Muscle cars, very few match numbers and I had a few cars with odd numbers. Sometimes, especially on bikes, I think that if they had a engine that was pulled off the line, fixed or repaired, it went into a bike or car that was waiting for this or any other engine. Who knows how many Bosnian, Serbs and Romanians worked in the factories in the 60's, displaced persons were common, people who replaced the 5 Million Germans who died in the conflict they started ( or was it the League of Nations that started it?). . !960 was only 15 years after WW2. I was in Germany in the 60's, the Devastation was quite extensive. I am sure there were all sorts of problems putting together a factory and a motorcycle at the same time.

All the same, I am happy to have had 40 or 50s bike in my life time all an experience on their own, some good, some bizarre and some just normal.

 

[ripperfarms]

Paint??????

I had a white R50 but it had small carbs and that ran good but was a little slower than the r60

I have a r/60/2, 1962, next to the tan R50/2?? that performs like a R60.

so, I will go out and compare closer, especially the number of fins and the "Pointy shape of the heads"

Thanks every one.

I will get back wit some Pictures.

That's a lot of good talk about engine size but here's an idea on the paint.

I had heard somewhere that you could order one of these bikes any color that was being painted on the cars. As the cars and bike of this era were assembled in somewhat the same factory. So the paint could be stock. On trick I have found to determine it has the possibility of being original is look under the tank, usually under the left hand side, the person that penned striped the bike put their initials under there. It may be on either side.

Granted it could be done by a repainter also if they new the original people signed the tanks. But it is a clue.

My 1966 R50/2 is Gray(I think BMW may call it green) and it has initials under the tank. So I think it is original. And the fact that the previous owner had it from 1977 and did not repaint it. It does need some touch up but I am not going to change the paint.

I'm not such a Dover White fan but I kind of like the brown of this bike.

If you ever want to sell let us all know........I think we're interested. ..........great bike.........dave in Illinois.

 

[ripperfarms]

12345678

And by-the-way......who cares about numbers.....the idea is the ride.......those are the same people that want a "like new" box with every old toy. Kids will tell you that playing with the toy is what counts not keeping it in the box.

Have a good ride...........dave in Illinois