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Tips

Jumpy Speedo

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60TR3A

60TR3A

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My tach is rock steady but the speedo needle is in constant motion, swinging a good 10 MPH or more so I never have a great idea as to what speed I'm doing. Aren't they both cable-driven and if so, what can be done to calm down my speedo?
 
The tach in the BJ8's are electronic. They may be for the BJ7's also?

Make sure the speedo cable is not bent too sharply traveling from the tunnel to the gauge. The connection at the gauge should be tight, but not too tight. Try tightening or loosening it there, to see if that helps. Check the connection at the transmission also.

Good luck.
 
Just checked and my tach has a big, fat cable leading to it so it's definitely mechanical. Also noted that the cable leading to the speedo has lots of play in it so it's probably too long. Maybe I need to zip-tie it to the frame so as to stabilize it and maybe this will keep it from being so jumpy.
 
61TR3A said:
Just checked and my tach has a big, fat cable leading to it so it's definitely mechanical. Also noted that the cable leading to the speedo has lots of play in it so it's probably too long. Maybe I need to zip-tie it to the frame so as to stabilize it and maybe this will keep it from being so jumpy.
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The "inner" cable is usually what causes a jumpy speedo needle. Find a speedo shop and they can make the inner cable.

If you can take the whole speedo cable out you can remove the inner cable and lay it on a flat table and "roll" it. If it jumps because it's oval shaped, you found your problem.
 
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