K8 speedometer vs. GPS readouts

[Warchild]

I am finding the Gen II Busa speedometer readings to be fairly typical of big-bore Japanese machines... readouts are optimistic across the range, with the margin of error increasing the faster one travels.

Went out today and took a few measurements at different speeds, comparing the stock speedo to a GPS in my tankbag's map-case. Here's some of the readings, they are not too surprising.

All figures are in mph.

Indicated - Actual
25.0 ------- 22.8
35.0 ------- 33.1
43.4 ------- 40.0
54.0 ------- 50.0
59.6 ------- 55.0
65.0 ------- 60.0
75.1 ------- 70.0
81.5 ------- 75.0
109.7 ------ 100.0

Of course, YMMV, yadda, yadda. But I never had less than five (5) NAVSAT signals locked onto me, using a clear open road in the flat steppes of eastern Washington (no canyons or anything that might cause momentary satellite signal drop). I did these runs twice and was able to duplicate the results every time, so it's probably pretty accurate.

It's nice to know I can stay fairly close to 75-77 mph indicated on the interstate, and not have to sweat things. :thumbs up:

Still, I need to be realistic about things; am still going to wire up my Valentine One well before next summer....

[buffalojoe]

I was always under the impression that regular civilian GPS'
were only accurate to within 3 meters... regardless of Sat's ..
Unless you are Military.. I think they are within a couple feet...

Either way that should make for some margin of error also, :umm:

JOe

[Warchild]

I was always under the impression that regular civilian GPS'
were only accurate to within 3 meters... regardless of Sat's ..
Correct as far as actual location (positioning) is concerned, but with regard to speed readouts, they are pretty dag-gone accurate.

I've done a lot of testing against police radar courtesy of some buddies who belong to the Washington State Patrol, and the GPS is uncanny accurate against them.

I'll likely be installing a Sigma in the near future, and those can be calibrated to within a c-hair of actual ground speed. Then we'll know. :thumbs up: