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Electrical · Tune data — verify against your model's manual

Ignition timing marks — late flywheel

Value
S = static 6° ± 3° BTDC
Applies · /7 onward — from the 1977 model year
BMW-TD77 Now sourced, and the boundary moves. BMW's /7 technical data gives ignition timing 6° ± 3° before TDC with a control range of 25° ± 2°30′ at the crankshaft — so full advance is 6 + 25 ≈ 31°, and mechanical advance begins at 1550 rpm and is complete at 3000 rpm. That is the /7 specification from the 1977 model year, not from 01/1978 as earlier revisions of this guide had it. OT = TDC. Strobe at F with rpm above 3000; verify S at idle. Sources put full advance at 31–34° depending on flywheel — the factory number for the /7 is 31.

This is the book's general row. In the book, pick your model and year and this figure resolves to your machine, with the one-page torque sheet, the job pages and the printable booklet.

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