stock speedo reads in reverse only

After i bought a new cable, it is still only reading in reverse. I see that the wheel adapter is 61 dollars. I am hoping that is the part that needs to be replaced, otherwise it is something with display. This sux but ive read that the Vapor uses a magnet. Can i hook up a magnet to my stock speedo display? how does it work?



I have tried to turn the cable every which way and still nothing. I did notice that the Speedo gear box has a silver pin hole inside of it that the cable slips into. Is that pin hole suppose to have any play in it? Mine does. I can move it back and forth almost half a CM or more.


Before you go off and buy anything, there are some simple things you might do to verify what device is at fault.

I would start by finding a reversible drill (or similar) and attempt to drive the cable itself (wheel end) with it both ways to verify if the issue is the display. The cable can be checked for any breaks by removing it from the display unit and watching (or trying to retard its rotation there) - this is not likely though. If the display works correctly both ways, the issue lies with the speedo gearbox, otherwise it is the display.

At $61.00, I would replace with a Vapor no matter if it is was the gearbox or display.

My 2c worth...


Can i hook up a magnet to my stock speedo display? how does it work?

You can install a Sigma Bicycle Computer on your bike. It uses a magnetic pick-up like the Vapor, and can be had for under $30.

There is nothing wrong with your OEM speedo. It has many functions, one of which is to count down miles. Read your owners manual, it will tell you all about it.

After i bought a new cable, it is still only reading in reverse.



Could you clarify if you mean the speedometer only works rolling the bike backwards or if you mean the speedometer works fine but the odometer appears to go backwards?

my speedo is only reading when the back is rolled backwards. it will read up to however fast i spin the wheel (going backwards) when i move the wheel forward, i have a 0 speed reading. It will not read the MPH in forward motion.

I want to say its the speedo gear at the wheel. I crashed in the dirt once and buggered up the cable. cable is ruled out. i dont see how i could have made the stock display malfunction from the slow fall that i had but who knows

Check that the gear set is turning when rolling forward. My guess is that it is not.

Assuming you moved the bike forward after the crash, and assuming the wrecked cable was jammed, it sounds like something stripped in the gear set but manages to catch enough to turn the cable going backwards. But that is just my guess.

I just went and rolled my bike back and forth, and the speedo reads + going either way, so I suspect it just counts pulses without any need to know which way the cable is spinning. Not like a bike is going to back up any great distance. This suggests that if you get any reading at all (which you do) then the speedo is ok. You could undo the cable from the speedo and watch the end to see if it turns while spinning the wheel either way.

As far as hooking a magnet up to your stock one, I don't see as there is any way to adjust the calibration for the number of pulses that equates to a certain speed, so it is likely more hassle than it is worth. The internal pickup could be from a magnetic encoder ring, or it could be optical. If it is magnetic, supposing you could even get the housing open, you could solder wires on and bypass the original one, but it just sounds like :bonk:

well i took the cable off at the speedo display and spun the tire and it will only spin the cable in reverse so it must be the gear

thanks everyone

if it turns in one direction I would think the gear is intact. Perhaps the metal arm bent, or (guessing) is there a metal insert inside the end of the gear that drives the cable? Might be fixable.

Only way to know for sure is to take it apart.

i took my speedo housing apart same problem mechanical gear worn. I think the old cable stuck while the gear still turn causing premature wear.

Took the seal up slide out the gear cleaned it. Ran a hacksaw blade just the blade trough the teeth.Sanded the bottom of the gear a couple mm"s then the bottom of the ears on the gear carefully. Now the gear grab some good teeth. Hope it last awhile or for good! Of course this was trial and error for me. You might do a better job measuring with a caliper to get a more accurate measurement. A belt sander might be better or any thing with a flat surface. My dremmel and a sanding drum did the trick for me! Speedo works( I love that tool) Post me with any question.

In the name of Hannible "I love it went a plan comes together" ATEAM

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