AJS & Matchless Owners Club

Try using talcum powder liberally applied to the rubber to help it to fit
and the rest of you can forget the comments
Tony

Mc-Maz wrote:The headlamp and speedo are original to one another.
Here's a picture of how the grommet is situated without being tightened - all of it sitting on top of the headlamp shell. Is this correct?

speedo bezel and grommet.jpg

I think you're suffering a bit from mathematics. The hole is a particular diameter. The casing of the speedo is a particular diameter, hopefully a teeny bit smaller than the hole. By having the speedo at an angle you've effectively made it into an ellipse with the longer dimension bigger than the hole, which means squeezing it in together with the rubber ring isn't going to work until you straighten it up.

Tried “a little more patience” and no joy - the bottom lip of the grommet will not fit into the hole in the headlamp shell.
The speedo body is more or less an interference fit into the opening in the headlamp shell. As you say Janet, any deviation from horizontal and the speedo body will not slide into the opening and that's without the grommet fitted.

The mathematics of it all are as follows:
Diameter of opening in the headlamp shell to accept the speedo body = 81mm
Diameter of speedo body = 80mm
Diameter of bottom lip of grommet when fitted to speedo body = 84mm

Seems the only solution in this case is to remove the bottom lip.

could you fit the grommet to the shell first and then use the speedo to squeeze the rubber as you push it in?

Janet wrote:could you fit the grommet to the shell first and then use the speedo to squeeze the rubber as you push it in?

Janet, tried that and no joy, opening way too small.

I mentioned it needed straightening, Janet also noticed this. Then Tony comes along with the talc. You will find the speedo may grip and not drop in. So a bit of patience, talc to help stop gripping effect, give it a little wobble and it should drop in. Brute force wont help, and as Janet says it will be bigger at an angle. I've never used talc, just a gentle wobble so it finds its way in. You may find getting the light switch in needs the same procedure. That needs to go right in tight so you can get the clip on. Brute force could brake the switch rim.
Still no joy???? Looks like you may have to scape the shell hole.

Mc-Maz wrote:

Janet wrote:could you fit the grommet to the shell first and then use the speedo to squeeze the rubber as you push it in?

Janet, tried that and no joy, opening way too small.

I think you need a bigger hammer.

I certainly would not try scraping what looks like a highly finished paintwork. The rubber basically needs to be between the speedo bezel and the headlight to allow the clamp to pull it down. With the dimensions you quote you are never going to get it to fit. Instead I would cut off the bottom part of the grommet and put a few turns of gaffer tape round the body and tighten it up. Job done and no-one will know, well ok we will

Hi

I had exactly the same problem on my 61 G3 and did as suggested, cut the lower section of the grommet off, works a treat but the wider section then fouled in the recess of the headlamp. Ended up using the off cut carefully flattened out to give an invisible seal.

Regards Mick

Mick D wrote:Hi

I had exactly the same problem on my 61 G3 and did as suggested, cut the lower section of the grommet off, works a treat but the wider section then fouled in the recess of the headlamp. Ended up using the off cut carefully flattened out to give an invisible seal.

Regards Mick

Mick, thank you – I was beginning to doubt my sanity.
Before seeing your post, I'd already bitten the bullet and cut off the lower section of the grommet. I intend to ensure that the remaining wider section makes a good seal by applying a thin bead of clear silicone to the mating surfaces and use release agent on surfaces where I don't want the silicone to stick.