Triumph Rat Motorcycle Forums banner
  • Hey everyone! Enter your ride HERE to be a part of October's Bike of the Month Challenge!
1 - 5 of 5 Posts

·
Registered
Joined
·
138 Posts
Discussion Starter · #1 ·
I did the old measured mile to get a good assessment of speedometer accuracy.Using my new bar mounted clock (with red sweep second hand)I got on the NY Thruway and did a mile a minute.It took 65 or 66 seconds.So I was slow by 8.5% to 10%.I did this a few times ;same result.
I then ran at an indicated 65/66mph and it took exactly one minute,so now I know .
I guess I will have to hit 110 to really break 100mph....The max 92 I have gone so far was really "only"about 85....oh well!!
 

·
Premium Member
2009 Bonnie A-1. 1968 T120R
Joined
·
1,049 Posts
Yeah, I find myself constantly doing math to know exactly how fast I'm going. It seems that the faster I go, the more off the speedo becomes. Does that make sense?
-Sparky
 

·
Premium Member
Joined
·
1,600 Posts
Arg! Just bought and installed a bicycle computer to test my speedo to see how far out it was. Whatever jury-rigging I had to do to get the spoke magnet and pickup to line up didn't work so now I have this $%^ bicycle computer on there with no more information.

Needed a bicycle computer any way for one of my push-bikes. Just thought it would provide me with some help for the Triumph first.

Should have just gotten the GPS in the first place. Have been afraid to get a GPS because then you end up needing the GPS mount and then you're outside in the open looking into a tiny screen again. Oh well.

I don't blame Triumph for their almost useless speedo because all the manufacturers make them innacurate on purpose. For liability reasons, apparently, so they won't be sued by a rider who didn't know he was speeding.

But I say, if they make a purposefully inaccurate speedo, why should I assume my speed must be lower than the indicated speed? No one puts it in the manual--"Owner beware your speedo is useless for knowing what speed you're going." Or, "be advised your actual speed is lower than indicated." Actually, maybe they do put that in there--I haven't read closely enough ;-)
 

·
Registered
Joined
·
138 Posts
Discussion Starter · #5 ·
speedo deviation

The speedo is further off the faster you go.I had a police radar unit measure my speed at 40mph;I was slow by "3 or 4 mph"according to the officer .
So,it is a percentage deviation rather than a set #.Got to do 110 to get to 100!
 
1 - 5 of 5 Posts
Top