Speedometer rubber grommet – part No: 021798

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Mick D
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Re: Speedometer rubber grommet – part No: 021798

Post by Mick D »

Hi

Could an explanatory note be added to the description for this part on the spares site? Contrary to what the spares list says I can't see any way this seal will fit this combination of speedo / headlamp without butchering.

Regards M ick
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Rob Harknett
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Re: Speedometer rubber grommet – part No: 021798

Post by Rob Harknett »

Janet wrote:
Rob Harknett wrote:Wrong. Prior to 1955 a different headlamp and speedo was used. The speedo did not fit in the headlamp prior to 1955..
No-one said the speedo did fit in the headlamp shell prior to 1955. Sean is comparing the models from 1955- with those from 1960 onwards.
The 55/60 headlamp hole for the speedo is 3 5/16" ( 184 m.m. ) dia.
I assume you mean 84mm? Sean has already said that the diameter of the hole in his headlamp shell is 81mm.
Yes 3 5/16" is about 84 mm Janet, I made a typo there. Sean seems to have a different headlamp to my 1955 bike and my spare shell. I have just looked at my 64 G12CSR which has a different speedo to 55 also a different headlamp. I also see no rubber grommet under the flanged bezel. Perhaps Sean has the later headlamp and he is trying to fit and earlier speedo with the grommet into.
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Rob Harknett
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Re: Speedometer rubber grommet – part No: 021798

Post by Rob Harknett »

Ashampoo_Snap_2017.03.18_12h22m58s_003_.png
Ashampoo_Snap_2017.03.18_12h14m00s_002_.png
Please see the two pictures Sean
1955/59 is the headlamp with the 3 5/16" 84 mm speedo aperture.
You would have the 1960 onwards headlamp, which must have the 81 MM aperture.
My bikes that have the 1960 onwards headlamp do not have the rubber grommet fitted,
Pictures are from Smiths AMC parts for 1955 (same pic in 1959 ) and new lamp in 1960 . This should explain the reason why you cannot fit the grommet. Because you have a smaller dia. speedo aperture
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McMaz
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Re: Speedometer rubber grommet – part No: 021798

Post by McMaz »

Rob – your excellent research backs up the info in the article I quoted in my earlier post (Fri Mar 17, 2017 2:00 pm).

Despite being included in the 1960 spares list and described as used on “All touring and CSR”, it seems conclusive that rubber grommet 021798 is not suitable for machines that have the 1960-on headlamp with the 81mm aperture.

As Mick D wrote earlier, it would be helpful if this info could be added to the description for this part on the spares site.

Sean
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Stuoyb
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Re: Speedometer rubber grommet – part No: 021798

Post by Stuoyb »

It still begs the question "what was used?".
The 1960 parts list shows 021798 as still being used, supplements issued in 1961, 62 & 63 do not show an alternative part.
If you want club parts to change the info then you need to send your information to them - spares@jampot.com
JimFitz
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Re: Speedometer rubber grommet – part No: 021798

Post by JimFitz »

On my 1960 G12 there was no grommet fitted and the speedo was almost an exact fit in the headlamp hole. I had a search through my old plumbing fiitings and found an O ring which I stretched out around the speedo and snugged it up under the bezel. Tightened up the clamp so it just nipped it and the job's a good'un.

Jim
Too old to Rock and Roll but too young to die.

1952 G80 rigid, 1960 G12 DL / Watsonian Monza, 1954 G80S.
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Rob Harknett
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Re: Speedometer rubber grommet – part No: 021798

Post by Rob Harknett »

The problem with spares list are, they would had been produced very early in the model year. They often used old artwork. There always seemed to be errors. Errata's were published, sometimes stuck in a parts list sometimes a loose insert. They got lost over time. A.M.C. also issued Service Sheets. Few of these survive. I believe service sheets, that were just typed and duplicated, only went out to dealers. Often they informed of changes being made. Mid year changes are not recorded in the parts lists that we are left with, to refer to. I am sure some of you may have come across a parts list, in which a dealer in the past, has made many changes to.

021798 is still listed in the " Master " parts list dated July 1960. That is just a month prior to when the 1960 model year ended. That is all what seems to survive for us to go by. From approx. 1960 onwards, parts list were mainly in the form of supplements listing parts that differ.
Perhaps a long lost note may be found one day, that refers to pt. no. 021798 being discontinued.
This may have been a Lucas or Smiths change. So if anyone wants to check. Look at the Lucas or Smiths AMC parts list for 1959, that featured headlamp MCH57 and compare the parts in the Lucas or Smiths AMC pars list for 1960, that featured the MCH61 headlamp. As the grommet will not fit the MCH 61 head lamp with the smaller speedo aperture, you may find it is not listed.
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