Post by chris9183 on May 7, 2013 14:03:03 GMT -5
Howdy.
I know most motorcycles (especially chinese scoots) have a 10-25% optimistic speedometer error. Just thought I'd share what I did to correct it with yall.
I borrowed my dad's dash-mounted GPS and did some speed tests on the roads around here. I tested speeds at 10, 20, 30, and 40 mph. The results are that my speedometer starts with a 25% error at low speeds, and actually becomes more accurate as the speed increases, down to 15% error at 40mph and up. The results:
Speedo Reading - Actual GPS Speed
10mph - 7.5mph (25% error)
20mph - 16mph (20% error)
30mph - 25mph (16.5% error)
40mph - 34mph (15% error)
The error leveled off at 15% at 40mph (and above I assume). So that means my speed at 50mph is actually 42.5mph, 60mph is actually 50mph, and 65mph (my top speed) is actually 55mph realistic. This is all assuming a 15% error.
So what I did was, I just took out my speedometer unit, used a bit of paint to remove the current numbers on the faceplate, and wrote in the correct numbers in their place with a white permanent marker. Problem solved for me.
Not really a revelation or anything, but figured I'd share what I did to fix this annoying problem. You can look at it two ways...it's either a problem with an inaccurate speedo cable/unit, or you can choose to just look at it as inaccurate numbers on the face plate, which is much much easier to fix than fiddling with gears and cables and potentially expensive stuff. If you want to get fancy and you're good with graphic design, you can even design your own face plate in a graphics program and print it out, laminate it, and make it fit your speedo plate.
I know most motorcycles (especially chinese scoots) have a 10-25% optimistic speedometer error. Just thought I'd share what I did to correct it with yall.
I borrowed my dad's dash-mounted GPS and did some speed tests on the roads around here. I tested speeds at 10, 20, 30, and 40 mph. The results are that my speedometer starts with a 25% error at low speeds, and actually becomes more accurate as the speed increases, down to 15% error at 40mph and up. The results:
Speedo Reading - Actual GPS Speed
10mph - 7.5mph (25% error)
20mph - 16mph (20% error)
30mph - 25mph (16.5% error)
40mph - 34mph (15% error)
The error leveled off at 15% at 40mph (and above I assume). So that means my speed at 50mph is actually 42.5mph, 60mph is actually 50mph, and 65mph (my top speed) is actually 55mph realistic. This is all assuming a 15% error.
So what I did was, I just took out my speedometer unit, used a bit of paint to remove the current numbers on the faceplate, and wrote in the correct numbers in their place with a white permanent marker. Problem solved for me.
Not really a revelation or anything, but figured I'd share what I did to fix this annoying problem. You can look at it two ways...it's either a problem with an inaccurate speedo cable/unit, or you can choose to just look at it as inaccurate numbers on the face plate, which is much much easier to fix than fiddling with gears and cables and potentially expensive stuff. If you want to get fancy and you're good with graphic design, you can even design your own face plate in a graphics program and print it out, laminate it, and make it fit your speedo plate.
