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Bottom End · Camshaft & Followers

Lobe lift / rocker ratio

Metric
308° cam: 6.756 mm · ×1.39
Inch
284° cam (R45 20 kW): 6.198 mm
Applies · by camshaft · 3.82 / 5.82
BMW-RA382 Lift follows the camshaft, not the displacement — a 450 cc R45 26 kW lifts the same 6.756 mm as an R100, because it runs the same grind. This guide previously labelled the row “750cc+”, which the revision workbook flagged as the wrong divider (item M-04) and which could not be fixed without this source. Valve lift = lobe × 1.39. Timing datum 2.0 mm clearance ±2.5°. Chain: 3/8×7/32", 50 links, single-row from '79.

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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