| Listed in parts books | Not catalogued by year yet |
ENGINE SPROCKET,21T MAC
A 21-tooth engine sprocket, part number M89/7, for the primary drive.
This is an engine sprocket, 21 tooth, listed under part number M89/7 in the older catalog notation. It's the drive-side sprocket that mounts to the gearbox or engine output shaft and carries the primary chain.
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Our records on this one are thin — the entry we have is a single terse line without a run of catalog appearances behind it, so we can't speak to specific model years or which primary chain pitch it's cut for. The manufacturer coding on file for this part looks off to us, since sprockets aren't something Lucas or Amal make, so treat that tag as unreliable.
If you're trying to match this to a bike you're working on, give us a call with what you've got and we'll confirm before you order.
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