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oldmowgli

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  1. oldmowgli

    Engine Prefix Identification

    oldmowgli posted a topic in Classics
    Hi, I have an engine (no frame at all) that I want to confirm as a Yamaha RD400 unit. The number is 8M4-002144, and this is in the correct position above the kick start, and does not appear to have been tampered with, but I can find no reference to this engine prefix anywhere - Google searches etc come up with nothing. It looks exactly like those in photo's of RD 400's and it has a pair of 28mm mikuni carbs fitted as it should. The Aircooled RD Tech forum lists dozens of RD model numbers but none start 8M4... Can anyone help me trace this to confirm that it is in fact from an RD400, and to determine age if possible ? I should add that I live in Australia ... if this has any bearing on the prefix.

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