Is anyone aware of a previous thread on the subject of disassembling, reconditioning and reassembling speedometers and tachometers?

The biggest challenge I'm facing thus far is the proper removal of the trip meter knob.  I have speedometers (and tachs) and have disassembled one of the speedometers for familiarization but it had a broken off knob.

The next candidate is in better shape with the operating trip meter knob intact and I'd sure like to keep it that way!

Replacement face decals seem to be available and the "glass" is actually plexi-glass so replacing those (if needed) shouldn't be an issue.  But I think I'll be ok there.  The color of the indicator needles is also good.

For now I need to figure out if the knob gets removed prior to removing the speedo from the body or pull it through (with the rubber shaft hole protector) and remove it when the unit is out.... and if it'll be obvious how to remove when apart.

If there's a tutorial, I can't find it.  I've used numerous search words and have come up empty.

Any guidance.... either to a thread(s) or direct guidance will be appreciated.


 

This might be helpful, good luck.
yamaha-enduros.com/index.php/forums/the-...knob-removal?start=0

I believe there is a teeny-tiny screw holding the knob on... 

Lens should be glass, not plexiglass as far as I know.

Most just send to DEET because he has tools and experience to make them look new at a reasonable price. 

There have been threads on here...  most don't go into too much detail but the basics are covered. 

The knob is definitely held on by a very small Philips head screw and it must be removed to get the guts out of the can.  Also, the lens is glass, for sure.  It sounds like you've figured out how to get the unit apart, but here is what I do.  I have a super small pair of SnapOn channel lock pliers that have nice 'teeth' on each face of the pliers. I use these to carefully open up the crimped ring. Those teeth are important, as it is a bit difficult to get ahold of the stainless ring to start the un-crimping process.  After you have done your repairs and restoration, clean up and dust everything and then re-crimp the ring.  I clamp a 1/2" piece of scrap plywood on the edge of my workbench, then using ordinary pliers, spanning the plywood and the crimp ring.  The plywood keeps you from destroying the crimp ring, even though it won't really show if you are using the rubber trim ring that the gauges are finished off with.

ALL VERY HELPFUL !!!   Thanks guys!

Pete, Mark & Kokomo.... You guys provided just what I needed to not be flying blind.
The screw (2mm for those that care) is out on meter #2.

  

The first meter I took apart definitely had plexi glass lens but I can see that  this wasn't it's first time being opened up.

On the remaining ones it's actually hard to tell just by gently tapping on the lens, but with the knob off I'll know soon enough.

Deet has done gauges for me in the past (along with oil pumps, wiring harnesses and an occasional odd ball something or other) but I'm testing my skills to see how well I do on my own.  If I'm not happy with my results then it's off to Deet they go.

An additional challenge will be whitening up the background on the 10ths wheels and freshening the numbers.

I have numerous units here for some trial and error and there's also consideration that needs to be given to effort/time vs. gain.

Thanks again. In time, I'll post the outcome if I stay the course.

I’ve seen a few posts where people use paint can openers to gently pry the ring lip. Patience and care required. I think it was Devin that posted pictures of a “crimping tool” to replace the ring. I don’t remember if it was a Yamaha tool but it was nice enough it could have been. 

I have glass available.
I also have decals for the gauge faces and odometer wheels.
I am reluctant to sell the decals because most folks don't have the skills to apply them.

Appreciate that Deet
I'll be in touch soon.
I'd rather support you and purchase within the "community" before turning elsewhere

Mark - I've been aware of the modified paint can opener method for some time.  Rather than use that I deferred to one of those small cheap pocket clipped screwdrivers that usually are handed out for promotion purposes.
Added my 90 deg bend and the results were good.
SMALL increments is the key!  Advance the width of the prying blade only as you work around the complete circumference.  If you advance in larger amounts the outcome will not be as nice, so you get back whatever effort you put in.
Once there's space completely around the body I use a SMALL square nosed pliers and squeeze til folded edge is straightened.... advancing around the circumference the width of the nose at a time.
The lens is definitely glass as discussed earlier, so the first speedo I disassembled which had evidence of having been worked on previously had it's lens replaced.
The results of my effort in the following  pics.....

 

...last two pics

Great job! 

Thanks for the pics.