1955-1966 BMW R26 / R27 Repair Manual (P/N 23009090280)

• Covers 1955–1966 BMW R26 and R27 motorcycles, detailing engine, chassis, transmission, and electrical systems
• Official BMW publication P/N 9099 136 (July 1962 printing, PN 23009090280)
• Contains 153 detailed technical figures, diagrams, and exploded-view illustrations for precise component identification
• Documents the transition and specific servicing requirements between the single-cylinder R26 and the higher-performance R27 build

Component and System Coverage

This factory manual provides an expert overview of assembly, adjustment, and maintenance specifications for the BMW R26 and R27 series. The document maps out the internal workings of the 4-stroke single-cylinder engine, including valve timing, piston clearances, and crankshaft installation. Beyond engine internals, this documentation gives technicians immediate access to vital tear-down parameters for the 4-speed transmission, foot-operated gear change mechanism, and rear-axle drive assembly. It focuses heavily on structural integrity. You will find specific alignment data for the frame, swing-arm suspension setup, and sidecar configurations. Having this information available as an instant download means no waiting for shipping—you can pull up the exact schematic you need right at your workbench.

Specification and Reference Data

Technical depth is established through comprehensive reference tables documenting tightening specifications, fluid capacities, and electrical values. The manual lists precise torque settings, such as cylinder head bolts at 25 ft-lbs and flywheel retaining screws at 123 ft-lbs. Intake valve clearance is specified at 0.15 mm (0.006") while exhaust valve clearance is set at 0.20 mm (0.008") in cold-engine conditions. It also includes dedicated sections for Bosch electrical components, specifying spark plug gaps and ignition timing metrics for precise tuning.

Please note that all service data provided here is for informational reference. Always ensure you possess the necessary mechanical qualifications, use appropriate personal protective equipment, and cross-reference the complete OEM documentation before undertaking any structural or engine work to ensure safe vehicle operation.