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/2 conversion

1961BMWR69S

1960R100S
Hello every one. Will I am o most done with a 2 year long conversion bike build. Took one year to get all the parts together. I don't know if any one is thinking about building one or doing one right know. My starting point was a 1965 frame, had a 77 R100s motor(last year for mech tach ), /5 headlight bucket and speedo, r65 lens-reflector H4 bulb, /5 wiring harness. I put the coil,starter relay, volt reg all under the tank with fab up brackets. The gas tank has a fuel valve on both sides know. /5 starter switch. Keeping the stock horn and headlight switch from a /2. The big thing I had a problem with was the drive shaft. I won't to use a /7 with a mech /2 bell but did not fit. Got the adapter plate and using a /2 drive shaft. I can wait to ride this bike. As soon as I'm done ill put pic up.
 
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Quite a collection of different bikes. Unless I missed it, it doesn't sound much like a /2 conversion?? An R65 frame and a '77 motor feeding a /2 driveshaft/final drive...the bulk of are Airhead parts.
 
1965 /2 frame

Hey Don you should post another picture as I don't think a lot people remember the first one. You can also use a LWB /5 or /6 drive shaft in the /2 swing arm housing and you won't need an adapter. The only modification is you have to turn the bell coupling section down a little in a lathe so it fits in the /2 swing arm housing. It bolts and slips right up to and on like it came from the factory.
 
I had a /7 long drive shaft and a mod /2 bell and it did not fit was to short. As soon as I get it all done I will post pic. The frame is a 1965 R50/2
 
I am interested in the driveshaft treament without spacer discussion

I once bought used a conversion bike which had what looked like later model /5 or /6 driveshaft with the U-joint assbly from a /5 - it seemed to work fine and I rode it for many miles till I noticed that
the spline cup at rear end of shaft was mostly gone due to not enough engagement onto the rear drive sprocket or spline part

I have always used a spacer on a /2 driveshaft since

Since I have a lot of /2, /5, and /6 parts can someone be more specific about just what combination makes a driveshaft for a conversion come out the right length without a spacer for my next project due this summer
 
46211;747757Got the adapter plate and using a /2 drive shaft. I can wait to ride this bike. As soon as I'm done ill put pic up.[/QUOTE said:
There are a lot of different designs of adapter plates out there. Some do not work so well. I have seen just a simple aluminum 4 hole spacer, which allows the drive shaft bolts to rub the drive shaft boot and tears holes in the boot after a short time.

The one that I designed years go, (and I still have them) used 8 bolts. 2 of the 8 are the old style socket head cap screws that early the early R50 - R60 used. These two socket head cap screws are cut down slightly, and the U joint flange of the /2 drive shaft covers them, so they can't back out. The other six bolts are of the later 12 point type. This is the plate I used in my conversion, as in this photo.
 

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Great looking bike. Vavle covers are awesome. I just bough that plate from you and it worked out great. Every thing looks just how it should. What I had at first was a /7 drive shaft with a /2 bell that was mech up, the taper on the /7 drive shaft was matched to the a /2 bell then heat treated again. The prob I had was it was to short to bolt up to the trans. What was to short was the bell was not on the rear end gear, the bell was on the edge of the gear. I'm running a 77 R100S motor( 40mm carb and a 336 cam) , 78 kick trans. Swing arm and the rear end are from a 1960 R60/2
 
You turn the outside of the bell

My understanding is you take a /5LWB or /6 drive shaft and bell coupling and turn the outside of the coupling(F.D. end)down so it fits inside the /2 swing arm housing. Don when you turned down the taper to fit the /2 coupling you actually shortened the drive shaft and the /2 coupling made it even shorter. I just gave a friend a complete /6 drive shaft for his conversion and that is what we found and what he did to make it work without the adapter stuff. You gotta post a picture soon!!!
 
Maybe that is way it does not fit. Lol... As soon as I get it all back together I will post pic. Hoping this weekend I will have it done. I'm still waiting on the header pipes from epco.
 
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Here is a picture of the bike all done. 1960 R100s
 
Interesting...kind of filled up the frame, huh? Had a chance to run it yet?

A couple of questions... It appears from the picture that both tires are touching the ground. Typically, they don't but it might be the angle of the picture. If they are, then it could be that the centerstand has gone farther over center than it should. Usually, the stops get banged around a bit. It might be made worse by the heavier engine now...so when you put the bike on the centerstand, don't just let it fall to the stops...try to hold it a little and let it settle.

The second thing is the angle of the driveshaft. Does it come more into align with the engine once it is off the centerstand? From the picture, it's at quite an angle. The angle on my stock R69S is not quite that severe when on the centerstand.
 
The bike runs great, its the picture. The rear tire is off the ground, the drive shaft has no angle. When its off the center stand the angle of the drive shat is inline . The bike is perfect,
 
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I know this is an old thread but is there any updated info on the swing arm mod to a later rear drive?
 
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