| Diagram | Fig. 23 — PETROL TANK, TWINSEAT AND CONTROLS · ref 50 |
| Subsystem | fuel |
| Listed in parts books | 1969–1970 |
BSA Exhaust valve lifter control
Exhaust valve lifter control, a handlebar/console-area control listed in the petrol tank and controls section of the catalog.
This is the exhaust valve lifter control listed under part number 42-8611. It shows up in the catalog under the PETROL TANK, TWINSEAT AND CONTROLS section, which tells you it's a handlebar or console-mounted control rather than something down in the engine itself. The valve lifter mechanism it operates lets you crack open the exhaust valve to relieve compression, usually for easier kickstarting or to stop the engine.
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Our records only show this part turning up in two catalog listings, spanning 1969 to 1970, and we don't have additional partner documentation on it beyond a bare listing elsewhere. That's a thin file to work from, so we're not going to guess at thread sizes, cable lengths, or which specific machine it bolts to.
If you're trying to match this up to what's on your bike, give us a call with what you've got in hand. We'll confirm fitment before you order rather than have you guessing off a catalog number alone.
We've never carried this one. Tell us what you're after and we'll go looking — you'll get a price and photos before you commit to anything.
Sorry if we got something wrong here. If you think this information isn't correct, .

