Some time ago I mentioned that a method of correcting the built in inaccuracy of the M3W speedometer has been found. The details of how to do this are in an article in the Morgan Three Wheeler Club "Bulletin" magazine and a link to that is here:
https://www.mtwc.co.uk/wp-content/uploads/2020/01/Bulletin-December-2019-speedo-calibration.pdf. This is free to view, even if you are not a MTWC member, although there is a lot more information about M3W's available to members if you look at the list above the article. The speedo correction is easy to do, once you know how and is essential if you plan on using lower profile motorcycle tyres, as the speedometer error will be in excess of the 10% over read error permitted for UK MOT's. It's worth doing even if you retain the standard size tyres, an error of about 6% is just not useful. As you will see, the most difficult part is locating the calibration plug.
