Speedometer- Glass replacement


The speedo on this bike had a cracked glass and a marked bezel. I will need to change the glass, but I'm going to try and tidy up the bezel and reuse. A new 60mm glass is around £8 but a set including new bezel and rubber gaskets is around £37 so I'll try the glass first. If all else fails I can get a kit later.  The process involves levering off the bezel where it is crimped around and behind the speedo lip, trapping the glass. The first step is to apply three layers of tape to protect the instrument body whilst levering.

Three layers of electrical tape to protect the case.



The next step is to fit a large ring clip to protect the side of the bezel and prevent it form being distorted outwards as the bezel is removed.

Large jubilee clip fitted to prevent distortion of the bezel

 The speedo is then inverted onto the clip to ensure its straight and evenly positioned.



The sides of the bezel can then be levered up using a small screwdriver against the instrument case. However this has to be done gently, moving only a little of the crimp at a time and raising it only a little- don't try to fold it up all in one. Try and raise the crimped part evenly and switch to a larger screwdriver as the rim is raised. Continue going around the speedo- raising the crimp a little at a time until finally raising it to vertical. In this position it will be close up against the encircling clip.

Starting to raise the crimp using a fine screwdriver blade


Finally I used a small pair of snipe nosed pliers to raise the crimp right up against the inside of the clip.
Crimp now vertical against encircling clip.


Remove the clip, twist to loosen the bezel and pull it off the instrument.

And ease the bezel off- care because the broken glass may fall out
Bezel removed- glass (some) remains attached to the speedo- note black crystalline material inside the bezel and some white debris inside the speedo.

The bezel was full of a crystallised black material- I've no idea if it was once rubber or if its some kind of sealant that has solidified. However I cleaned it all off and cleaned the bezel in the sonicator. 

I removed any remaining glass by slipping a narrow blade behind it. Care because there is a thin rubber sealing ring between the glass and the instrument itself which I wanted to leave undamaged and in place.

Using a blade to remove the remaining glass-note the black (and white streaked) rubber washer behind it.

Make sure to empty and debris out of the instrument and to clean the new glass on both sides. I polished the cleaned bezel and then used this material (Loctite 5699) grey RTV gasket compound to fill in the recessed part inside the bezel. 

RTV sealant used to seal the bezel

The glass was offered up to the rubber sealing ring which remained on the speedo body, before the instrument was lowered into the coated bezel.
Instrument and glass inverted onto the RTV filled bezel

The instrument was cleaned of any excess sealant (meths soaked tissue) and left inverted overnight for the Loctite to set. The bezel crimp was carefully tapped back down to hold the assembly the next day.


In order to recrimp the bottom of the bezel first refit the jubilee clip. Then using a small screwdriver and levering against the clip start to fold the bottom back down towards the base of the speedo rim. Work around as many times as you need- increasing screwdriver size if it helps. Aim to generate a smooth fold over although some peaks are inevitable. Finally place the speedo on a soft support and start to tap the crimp back down flat using a hammer and a fine punch. This was tricky and in order to use a broader punch I had to remove the clip. I finished off using snipe nosed pliers with tape on one jaw to protect the front of the bezel. Do as much as you can inside the jubilee clip because tapping or levering out of the clip will introduce distortions into the ring. I found out the hard way! If you are using a new bezel these I believe are secured by a few fold over tabs rather than having to flatten out the entire perimeter. However, if refitting the original the task is long and requires much patience probably more than I have. In the end I achieved a close but imperfect re-crimp similar toa pie crust, but I was loathe to go further in case I broke the new glass. I therefore sealed the somewhat crinkled edges of the crimp with more Loctite to prevent water ingress. The final effect is at least better than my starting point but sadly the bezel is distorted slightly. Hopefully this will not be obvious from the riders perspective.











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