Speedo Conversion

Back again with another issue on the '97 VFR750. I think I've got the issue pinned but appreciate a second opinion. The bike was originally imported from Belgium so had a KPH speedo on it. The previous owner had put a sticker conversion on the clock face which worked fine, but blocked the backlighting so you couldn't see it when riding at night. He also sold it to us with a NOS MPH speedo.

When we had the bike apart to replace the O-Rings in the leaking carbs I decided to take the time whilst the fairing was off to swap to the new speedo. Comparing the two side by side it seemed like a straight swap would work out (e.g the 220kph aligning with the triangle on both)



Having ridden the bike it was pretty quick to suspect the swap would not actually work out straight forward (either that or everyone else is driving way under the limit everywhere!) So this morning I ZipTied a GPS speedo to the yoke to go out and compare, 50mph indicated turns out to be around 63mph GPS and it seems to be consistently underreading by 20% throughout the range.

A quick look on CMSNL and it turns out the speedo sender (part 19 below) is actually a different part number between the UK bike and the EU spec, but everything else seems to be common between the two.



Would it be a fair guess then that if I source a UK speedo cable swapping them over will likely solve the issue? Or does anyone happen to know if there is anything else electrically between the two that will need sorting as well? Worst case it seems like speedo healers are available for the bike but I suspect getting a cable from a breaker will be substantially cheaper