Speedometer/Odometer reads from motor shaft, NOT front wheel!!


mlbco

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Maybe this has been mentioned before, but I just discovered that my MXR distance and speed readings are coming from the motor shaft and not the front wheel. This means the readings are WRONG if you change sprocket size, tire size, or let the rear wheel spin. I'm installing a Trail Tech Endurance 2 ride computer with front wheel sensor to overcome this issue.

Steve
 

Philip

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This is the cheapest way to measure the speed, no additional hardware is needed. There is no ABS on these bikes, so installing a wheel speed sensor and a wire harness to it would have cost extra money and would not have been appreciated by guys who do not watch their speedometers, or do not change from the stock gearing.

Not sure about the MXR, but my MX reads the speed about 10% above what my cell phone's GPS reads. Gearing it up by 1 front sprocker tooth would actually make the speedometer more accurate.
 

mlbco

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The industry standard (KTM, Beta, Husky, Honda, Yamaha ....) is a front wheel sensor for obvious reasons. Cheap doesn't cut it for me on a $10K+ motorcycle, it's the attention to detail and a device that is at least nominally accurate that makes the difference. The Trail Tech is a $90 upgrade that will outperform the nearly useless Alta computer that does not even include a trip odometer, average speed, or max speed output. All of these functions could have easily been done with fairly simple software additions, but I'll be forking out 90 additional dollars to get it done right.

Steve
 

Philip

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The MXR having a speedometer and an odometer is an extra that you do not get on other motocross bikes. The motocross industry standard is to have no speedometer. Honestly, I think there could have been no LCD display on the MX/MXR at all, if there was another more robust way to display the battery state and which map mode you are in, and most riders would have been okay with it. A real speedometer is more appropriate on the EX/EXR model, that I would support.
 

mlbco

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My friends and I converted a CR 125 to electric power in 2008 and even that bike had a functioning ride computer! :) The bike cost $6000 total to make and although it had less than 1/2 the power of an MXR it worked reasonably well as an electric off-road bike.
Ride computer.jpgRide computer.jpg
 

Philip

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WOW! That's impressive. Did you think about starting an electric dirt bike company? If you had built and sold a few of those, we now could have been talking on a Steve Moto Owners Forum! ;)
 

mlbco

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WOW! That's impressive. Did you think about starting an electric dirt bike company? If you had built and sold a few of those, we now could have been talking on a Steve Moto Owners Forum! ;)

I met with the founders of Alta around 2008 when they saw this video on YouTube. I encouraged them not to make the mistake Zero had made at that time, which was to build a glorified electric mountain bike rather than a full-on electric dirt bike. There was no disagreement between us on that point! Some of my friends who worked on this were also involved in Mission Motors, a now defunct electric street bike start-up. In 2008 I was barely surviving manufacturing drones, so there was no way I was going to switch businesses to something that might actually make money ! :)

Thanks,

Steve
 

strider

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I met with the founders of Alta around 2008 when they saw this video on YouTube. I encouraged them not to make the mistake Zero had made at that time, which was to build a glorified electric mountain bike rather than a full-on electric dirt bike. There was no disagreement between us on that point! Some of my friends who worked on this were also involved in Mission Motors, a now defunct electric street bike start-up. In 2008 I was barely surviving manufacturing drones, so there was no way I was going to switch businesses to something that might actually make money ! :)
Ah Mission Motors. I REALLY wanted one of those. I was able to ride one of the prototypes up on Skyline back in 2013. They still have my $1,000 deposit :muutt: I keep hoping someone will pick up the bones and make that bike. I will definitely buy one.
 

mlbco

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I installed a Trail Tech Endurance 2 ride computer and tested it on the street. With a claibrated front wheel size it reads roughly 10% faster than the Alta computer with the current gearing and rear wheel I'm running. I cut into the foam housing for the Alta computer and installed the Endurance mount with glue (Goop.) The computer is removable with 2 bolts if needed. Now I have a trip odometer and a max spped+avg speed indication for each ride.

Steve

Endurance Computer.jpg
 
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