Speedo Accuracy in Videos - is 204 mph really 204 mph?

[FullTilt]

http://ca.youtube.com/watch?v=IcKcCy7aodA

For a long time, I've wanted to show a video where the speedo and a GPS are framed together that shows the GPS unit sweeping past 200mph.

The old superkaos video showing his freeway blast where the speedo sweeps to 220+, but SK himself said it was wildly off in terms of accuracy but has been seen untold millions of times and hyped because of what it shows.

This is an Anderson Turbo equipped bike (very cool owner/rider BTW) with a stock wheelbase that just flys.

It might not be record-territory, but it is still pretty cool.

[caddydaddy]

That was pretty cool! Everyone says that bike speedometers are off by up to 10%. I'll have to see how much mine is off, at highway speeds of course!

[Steel]

I know for a fact MY speedo is off by a good 10%. I just automatically correct in my head and still ride 9mph over

[aussieidiot]

all speedos are out by up to 10% and even further at the limit. I had footage of my blade at 286kmh on a racetrack but it was no where near that.

I changed gear ratios and then i fitted a speedo healer, and my speed dropped to 265 but felt faster because of the new gearing.