Yes, I now know that my B44 speedo is 10 mph over reading. I had already recalibrated my C15 speedo, which reads 15 MPH over. (Plastic tape at 10 mph steps.
I have found it difficult to check with my satnav, which loses its battery power very soon on the bike. I will have to provide a 12 volt tapping.
Reading the small satnav speed is difficult, on the bike.
My real inquiry was to find out if ALL B44s are failing to reach the advertised top speed.
I know that my super rocket engine in featherbed frame bike would reach 100 mph 'on the clock' but I only did that once, to find out.
I never thought that speedos might read incorrectly, in those days. (1960s)
Traffic was much slower then, so my normal top speed would have been about 70, I was used to overtaking most of the time.
I travel over the country, mostly on Motorways, in my VW bus. This will keep up with the general flow - 80 to 90 MPH.
I often reach 100 mph, following sports cars or super-cars. It amuses me to think that those drivers see a white haired old geezer in a big van, on their tail!
Yes, I am naturally competitive. I was a trials rider for some years, and for most of my life i have competed with model aircraft ( word champion 3 times, national champion 17 times.
Mick
If I wanted to just cruise along at modest speeds, I would have stayed with my little Bantam. Light and easy to manhandle.
I tried a 250cc Yamaha virago, which only weighed 300 lbs. It easily reached over 80 mph, with more to come, had I tried. But I wanted a classic BSA.