Steamer Speedo how to open for repair

[Sin_Tiger]

The original clocks on mine are very hard to read at night, the card black has faded probably after being left uncovered in the sun for years.

I managed to source a good set of low mileage items in the UK but being a pedantic so and so I wanted the ODO to match the actual mileage, so rather than just do what a normal person would I decided to open the speedo up to reset it.

I've done this a few times on older cars so I knew it could be done and how to go about it but bike clocks have a few more challenges in store.

The crimped alloy around the bezel is very narrow and the body is plastic rather than older steel cans.

First job was to get it out of the frame. For this you need a long stem phillips screw driver, watch maker of electronics trimmer type, to remove the trip reset knob, once the screw is slackened it just pulls straight off, the spindle section is a "D" type round with one flat. Careful not to loose the screw, it is tiny.

Once removed it's time to tackle the bezel crimp. It can be prized out ward with some care. It is not very strong in itself so it needs to be supported to stop it bending, for this I used a hose clip of 70-85mm dia. If I do this again I would put some tape on the inside of the hose clip to stop it scratching the bezel paint.

Now the crimp over can be prised up to near vertical (clock face down). I tried a few tools with varying effect and level of damage, before I decided to make a special tool. I used a longish stem flat bladed screwdriver which I heated the tip and bent it in a curve to about 45 deg to get the leverage necessary. Again with experience I found that rounding off the sharp edges of the tip reduced the damage.

Gently does it with a lot of patience

Again if I was doing this again I would wrap some tape around the body as it's soft and easily marked. <!-- s:roll: -->:roll:<!-- s:roll: -->  and eventually the bezel will pull off quite easily.

Once opened, unscrew the two phillps retaining screws on the back of the casing and the guts come out easily.

You now have to work on the back with the face down so take care to protect the card, the needle and it's spindle while you work, they are eay to damage.

Adjusting the ODO digit rings is quite easy now by simply inserting a thin flat blade between the digit rings to disengage the gear teeth and turning the ring by a finger, you will not get it right first time but it's no problem to repeat the process till you get it right. Ensure all the rings are properly engaged  by trying to rotate them, there should be slight play, if one doesn't move a little it's not properly engaged with the adjacent ring.

Sorry I forgot to take a photo but it's should be quite obvious. Assembly as they say is the reverse of dismantling. Once everything is clean, you did clean the glass and card of all your grubby prints didn't you  <!-- s:roll: -->:roll:<!-- s:roll: -->

TIP - put some tape over the trip reset hole and the two back light holes to stop anything falling in once assembled, the give a quick blow to rid the internals of any dust or fillings.

When you put the bezel and glass back on, you will need to keep a little pressure on the back of the casing while it's face down to compress the rubber seal just enough to allow you to bend the crimp back over for a tight fit.

It's tempting to get heavy handed here but find those final reserves of patience. To crimp back over the bezel edge is just as tricky. I used a thin piece of wood to place the face on and then a pair of water pump pliers with soft grips or some tape wound over the serrations and sharp edges to push the edges back over as far as possible. I could get it absolutely back to original so get get it as far as possible I used a mandrel made from a piece of plastic drain pipe socket 75mm dia pipe that with a little trim slipped over the casing body, then gentle tapping around with the face on a soft surface, leg in this case, got it near flat, or at least enough that it would sit in the rubber ring without distortion..

The assembly now goes back in the frame BEFORE you put the trip reset knob back on  <!-- s:roll: -->:roll:<!-- s:roll: -->

I am satisfied with the finished job but with what I learned I could probably do better next time, hopefully you will if you have to.

Not been refitted yet but I will update when I have her running again.

I'll bet at least some of you jokers thought I sit on my backside and let my mechanic do it all  <!-- s:P -->:P<!-- s:P -->

[metalguru]

Years ago when we used to 'work' on speedos, we used to leave a note inside the case stating OH NO NOT AGAIN!!

Nice write up.

[Sin_Tiger]

we used to leave a note inside the case stating OH NO NOT AGAIN!!

 :lol: wish I'd thought of that.

[rf9rider]

Good info, wondered how the reset knob came off, want to get my speedo out so i can get the frame powder coated  :)