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Hello, I'm new to this forum so please correct me if I'm posting this in the wrong place. I just got a new digital speedometer and have wired it up to my 2014 1100 where everything reads correctly except for the speedometer and odometer. The speedometer I purchased is fully digital and came with a new speed sensor. Could it be that I need to install the new speed sensor for this to work instead of using the one that is original to the bike? If so, how do I do that when the new sensor has three wires and the old on only has two?
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Welcome to the forum, wanobiben.
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Hey wanobiben, welcome to the CB1100 Forum.
Share pictures and manufacturer details (e.g. site URL) of the new digital speedometer?
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[attachment=15252]
(04-09-2022, 09:44 PM)GoldOxide_imp Wrote: Hey wanobiben, welcome to the CB1100 Forum.
Share pictures and manufacturer details (e.g. site URL) of the new digital speedometer?
Thank you! I bought it off of Ebay. I later found out it is a Koso RX4N. I have attached the wiring diagram according to the Koso, and a wiring diagram from Honda. I matched them together on a spreadsheet. Everything works (tach, fuel, hi-beam- L&R Turn, Neutral, Oil Pressure) except for the speedo and odometer.
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Disregard the rear wheel speed sensor the slotted pickup ring - might as well chuck them. The Honda setup counted each one of those slots. The KOSO counts only one pulse per wheel revolution, as it passes by the supplied magnet.
If the wires are too short to run to the rear wheel, you can run it to the front, but you will have to affix a magnet to the disc somehow, and the sensor to the fork or caliper. You should have instructions to program it to the wheel size.
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(04-10-2022, 03:24 PM)pekingduck_imp Wrote: Disregard the rear wheel speed sensor the slotted pickup ring - might as well chuck them. The Honda setup counted each one of those slots. The KOSO counts only one pulse per wheel revolution, as it passes by the supplied magnet.
If the wires are too short to run to the rear wheel, you can run it to the front, but you will have to affix a magnet to the disc somehow, and the sensor to the fork or caliper. You should have instructions to program it to the wheel size.
Update: I ignored the original speed sensor on the bike and made some modifications to install the magnetic one that the KOSO came with on the front wheel. It is now reading a speed but it seems off. The parameters on the KOSO speedometer ask for the circumference of the wheel in millimeters. My front rim is 18" (approx. 457mm). If my math is correct then the circumference would be 56.5" (1435mm). I input 1435 into the KOSO and the speed seemed to read about half as fast as I was going, so I tried to double it and it still seems off by about 5mph. I could be wrong though as I'm just going by feeling. Should I include the tire in the circumference measurement and not just the rim?
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(04-10-2022, 11:40 PM)wanobiben_imp Wrote: (04-10-2022, 03:24 PM)pekingduck_imp Wrote: Disregard the rear wheel speed sensor the slotted pickup ring - might as well chuck them. The Honda setup counted each one of those slots. The KOSO counts only one pulse per wheel revolution, as it passes by the supplied magnet.
If the wires are too short to run to the rear wheel, you can run it to the front, but you will have to affix a magnet to the disc somehow, and the sensor to the fork or caliper. You should have instructions to program it to the wheel size.
Update: I ignored the original speed sensor on the bike and made some modifications to install the magnetic one that the KOSO came with on the front wheel. It is now reading a speed but it seems off. The parameters on the KOSO speedometer ask for the circumference of the wheel in millimeters. My front rim is 18" (approx. 457mm). If my math is correct then the circumference would be 56.5" (1435mm). I input 1435 into the KOSO and the speed seemed to read about half as fast as I was going, so I tried to double it and it still seems off by about 5mph. I could be wrong though as I'm just going by feeling. Should I include the tire in the circumference measurement and not just the rim?
Update: I ignored the original speed sensor on the bike and made some modifications to install the magnetic one that the KOSO came with on the front wheel. It is now reading a speed but it seems off. The parameters on the KOSO speedometer ask for the circumference of the wheel in millimeters. My front rim is 18" (approx. 457mm). If my math is correct then the circumference would be 56.5" (1435mm). I input 1435 into the KOSO and the speed seemed to read about half as fast as I was going, so I tried to double it and it still seems off by about 5mph. I could be wrong though as I'm just going by feeling. Should I include the tire in the circumference measurement and not just the rim? Definitely include the tire diameter in your calculations.
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[/quote]
Definitely include the tire diameter in your calculations.
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That is unfortunate. When I calculate the circumference with the tire it is about 1988mm. The default setting on the speedometer was 1900, and at that setting it felt like it was reading half the speed I was going. The unfortunate part is that the max setting is 2,999 so I am unable to double it to be more accurate. Guess I might need another speedo
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(04-10-2022, 11:40 PM)wanobiben_imp Wrote: (04-10-2022, 03:24 PM)pekingduck_imp Wrote: Disregard the rear wheel speed sensor the slotted pickup ring - might as well chuck them. The Honda setup counted each one of those slots. The KOSO counts only one pulse per wheel revolution, as it passes by the supplied magnet.
If the wires are too short to run to the rear wheel, you can run it to the front, but you will have to affix a magnet to the disc somehow, and the sensor to the fork or caliper. You should have instructions to program it to the wheel size.
Update: I ignored the original speed sensor on the bike and made some modifications to install the magnetic one that the KOSO came with on the front wheel. It is now reading a speed but it seems off. The parameters on the KOSO speedometer ask for the circumference of the wheel in millimeters. My front rim is 18" (approx. 457mm). If my math is correct then the circumference would be 56.5" (1435mm). I input 1435 into the KOSO and the speed seemed to read about half as fast as I was going, so I tried to double it and it still seems off by about 5mph. I could be wrong though as I'm just going by feeling. Should I include the tire in the circumference measurement and not just the rim?
Update: I ignored the original speed sensor on the bike and made some modifications to install the magnetic one that the KOSO came with on the front wheel. It is now reading a speed but it seems off. The parameters on the KOSO speedometer ask for the circumference of the wheel in millimeters. My front rim is 18" (approx. 457mm). If my math is correct then the circumference would be 56.5" (1435mm). I input 1435 into the KOSO and the speed seemed to read about half as fast as I was going, so I tried to double it and it still seems off by about 5mph. I could be wrong though as I'm just going by feeling. Should I include the tire in the circumference measurement and not just the rim?
Circumference at the tire riding surface is: 2873 mm.
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If only there was a formula for calculating the circumference of a circle
