Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Speedometer Calibration

Follow up to my previous post - I carefully scraped the insulation off one side of the wire shown above and soldered a wire to it. I then put a connector on the other end and hooked it up to a press switch. I double checked the voltage across the switch with the ignition on and it showed the expected 5V. I then followed the programming sequence in the Morgan Three Wheeler Club note and everything worked as expected. One note I would add is that a 'long press' means hold it down until the display changes as expected.

My M3W was shipped from the factory with the pulse setting at 3295 (not 3795 that apparently is normal), which explains why the speedo was over-reading by about 20%! Next long trip I'll double check the Avon setting of 4060 against Waze.

Others who can't find the programming plug may want to see if they can spot the black/gray wire to avoid having to remove the bulkhead, although you do have to risk cutting the wire when you strip the insulation so you might prefer Lance's approach if that scares you.

Glad it all worked in the end JohnMat. I assume your car is a more recent one? I think there may have been a few changes to the wire loom about the time of the Euro 4 spec cars introduction, early 2018. Possibly the black/grey and black wires plug was deleted as it seems to be very elusive on later cars. Your fix and splicing into the black/grey cable at the speedo achieves the same result. You may need a little adjustment after a check run but it will be a lot closer than when set at 3295, although your 0-60 time won't be so impressive now!

Hi Planenut, just a quick update.

After you changed my setting in Grindelwald last year with the Blockleys on it was bang on I now have Michelin Commanders on and it only reads 2 fast at 30 mph. So I'm going to leave it as is.

Good to hear it all worked as it should Dab. You have done the tricky bit, finding the plug. It's easier than programming a central heating system to change the numbers and get the Michelins reading correctly . Try 004400 as a starting point......before you wear the Michelins out!

FYI, my Pirelli Night Dragons in 110/90R19 size wanted 004200 to show perfectly on my 2013 cars' speedo.

Yes, mine is a Feb 2020 build. And I'm having too much fun to care about 0-60. Smiles per gallon is off the charts!

Finally updated my speedometer - it's been annoying me since I picked-up the car. Mine is a 2017, built March 2017. I was not able to find a grey/black connector anywhere on my car.

By the way - the purple/grey and black connector has 12v on it and is for the 12V outlet and intercom when fitted. If you short those two terminals together you'll blow a 15A fuse :-)

However, I did find the black/grey wire in one side of the 20-pin black connector above the fuse box. The other side of the connector was empty. I stripped a wire, pushed it in the open connector location, and hooked it to an old doorbell button, and then connected the other wire from the switch to the black ground wire at the intercom connector (but any ground will do). Simple, didn't have to strip any wires or solder anything, and worked perfectly.

I did find that the speedo came up in "Input" mode, and I had to cycle through to get to "Pulse" mode.

The suggested 004045 setting from the article for the Blockley's - on my car - was too low and resulted in speedo readings still 3% to 4% high. I added 3.5% to the 004045 to get to 004185 and the speedo is spot-on accurate now.

Pics of the connector with the black grey on one side and open terminal on the other:

Thanks for that info Truckin-on, that should help owners of newer cars to find the correct wire. I think the Blockleys have a lot of tread when new that alters the speedometer reading quite a lot. I set 004045 when they were new but they are about half worn now and I have 004100 to get the correct reading against my GPS, it could actually be closer to 004185 but I have gone with slightly over reading.

I checked my speedometer with the gps today. It is right at 5 mph fast. It is funny, every motorcycle I have ever owned is 5 mph faster than actual speed. And it is across the brands, Honda, BMW, Kawasaki, Harley, Indian have all been 5 over. Is that a standard with motorcycles?

I use the gps unit for the speed.