Hi all
I recently read a short article in the MiniSpeed catalogue - it may well be repeated on their web site?
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Page 67. Speedo cables and speedos DO NOT (it says here...) determine the correct callibration of speed: they simply read what they are told from the gearbox. The speed calculation takes place through the speedo drive gears in the greabox. These need to be changed when altering final drive or wheel size in order to maintain an accurate speedo reading. Please see gearbox section for more information.
There is too much on that page for here, but it makes interesting reading.
I suppose you could recalibrate the head - and thats a lot easier to get at... Don't know. Long way to go before I start worrying about that. Come to think about it - no - I need to plan this before the engine goes back together. Too late once its all bolted in. :-)
Hope helpful
Peter