The 1955-1969 BMW R50, R50/2, R50S, R50US, R60, R60/2, R69, R69S, R69US motorcycle repair manual by Clymer, covers the following models of 500cc and 600cc twin-cylinder bikes:

• BMW R50
• BMW R50/2
• BMW R50S
• BMW R50US
• BMW R60
• BMW R60/2
• BMW R60US
• BMW R69
• BMW R69S
• BMW R69US

Book Excerpt: 1955-1969 BMW R50, R50/2, R50S, R50US, R60, R60/2, R69, R69S, R69US Repair Manual CHAPTER SEVEN | IGNITION AND CHARGING SYSTEMS

CHARGING SYSTEM: GENERATOR There are 3 generator models used. The 6-volt, 60-watt unit. (Figure 5) is used on most models in this series. An optional 6-volt, 75-watt unit and a 12-volt, 100-watt unit (Figure 6) are used on some R 50 S, R50-2, R 60-2, and R 69 S models. With the exception of its performance, the 75-watt unit is the same as the 60-watt unit. Some very late models have an optional 3-phrase alternator. This unit is discussed later. Determine which unit your motorcycle has and proceed accordingly. The generator is driven off the end of the crankshaft. It produces its rated output at an engine speed of 1,700 rpm, and its peak output at 2,100 rpm and above. PRELIMINARY GENERATOR TEST

1. Start the engine and bring the speed up to about 2,500 rpm.
2. Switch on the lights and disconnect battery ground lead. The brightness of the headlight should increase slightly.
3. Reconnect the ground lead. The light should decrease in brightness slightly. If the light performs the opposite in either case, the generator output current is insufficient and the generator should be thoroughly checked.

CHAPTER FOUR | ENGINE

To remove the engine, it is necessary to remove the transmission (see Chapter Five) and the drive train (see Chapter Eleven). Refer to these chapters, perform the necessary steps, and continue as follows. CAUTION! Disconnect the battery. If you attempt to remove the front cover without disconnecting the battery, it is likely that the cover will short against electrical connections. REMOVAL

1. Turn off the fuel tap and remove the hoses from the carburetors.
2. Unscrew the carburetor covers and remove them and slides from carburetors (Figure 1).
3. Unscrew the exhaust pipe connector rings with a pin wrench (BMW tool No. 338 / for R50 and R60, No. 338/2 for R 69). See Figure 2.
NOTE: When reinstalling the exhaust pipes, the threads on the exhaust flanges and connector rings must be coated with coarse, dry graphite grease.
4. Remove the 19mm nuts from the ends of the rear engine mounting rod (Figure 3).
5. With a soft-face mallet, tap the rod to the right and remove the left exhaust pipe clamp and footrest. Then, tap the rod to the left and remove the right clamp and footrest.

Subject: 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969 BMW R50, R50/2, R50S, R50US, R60, R60/2, R69, R69S, R69US service, maintenance, repair. ISBN-10: 0892872241 | ISBN-13: 9780892872244 Clymer M308