Author Topic: Speedo & Tacho mounting plate  (Read 335 times)

Offline Rudgeman

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Speedo & Tacho mounting plate
« on: 06.08. 2019 14:51 »
Hi again.

I said in my last post the front end of this project was a saga - well the sga continues.

One objective was to replace the single speedo arrangement with a tacho & speedo. The tacho was pretty expensive but the other parts were quite reasonable.

I've just got to the bit where I mount the speedo and tacho plate (complete with speedo & tacho) to the top yolk - and it doesn't fit ! The plate is flat and expects to be sandwiched between the stanchion top bolts and the yolk ends as well as by 2 small bolts in the middle that bolt to small bosses on the yolk. Since the plate is flat I expected the top of the bosses to line up with the tops of the yolk ends where the stanchion bolts fit - but they don't ! They're about 3.5mm higher than the yolk ends - see attached photo.

So either I have the wrong yolk - and the bosses should be 3.5mm lower, or else I should be fitting 3.5mm spacers underneath the mounting plates uner the stanchion bolts. The problems with the latter are :
a. There's no mention of spacers in the parts lists and diagrams.
b. I'll need longer stanchion top bolts. I estimate, with spacers in place, I'll only have about 3-4mm of engagament between the bolts and the stanchions - and that doesn't feel right.

Since having both tacho & speedo was an option for a 1962 Super Rocket, and there's only 1 parts number of top yolk for that year - there must be a solution - but I don't know what it is. The impatient me wants to cut 3.5mm off the bosses - but the more sensible me thinks I ought to get some advice from people who've been here before.

Any advice would be most welcome.

Kind regards - R

Online berger

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Re: Speedo & Tacho mounting plate
« Reply #1 on: 06.08. 2019 15:20 »
them there sticky up bits came in really handy when I did mine *smile*

Online JulianS

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Re: Speedo & Tacho mounting plate
« Reply #2 on: 06.08. 2019 15:56 »
2 top yokes share the same casting number 42 5035.

42 5035 is the part for top yoke with nacelle. Not usually drilled for tacho mount.

42 5036 (casting 42 5035) is machined differently so that the drilled pips which stick up are level with the surface for the fork nuts.

Photo below.

Offline Rudgeman

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Re: Speedo & Tacho mounting plate
« Reply #3 on: 06.08. 2019 16:03 »
Thanks Julian,
                           I wish I'd realised that before I painted the top yolk ! Never mind.
Thanks again,

Offline trevinoz

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Re: Speedo & Tacho mounting plate
« Reply #4 on: 06.08. 2019 22:57 »
Then again it could be an A65 top yoke which has the higher bosses.

Offline duTch

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Re: Speedo & Tacho mounting plate
« Reply #5 on: 06.08. 2019 23:06 »

 I say it's a wrong yolk-  *bright idea*  you need a different yoke
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy

Offline Gerry

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Re: Speedo & Tacho mounting plate
« Reply #6 on: 14.09. 2019 02:18 »
Hi Rudgeman, Just a thought, can you drill out the bracket to fit over the two "pips" that were originally for the speedo mount?
I believe this would be the easiest solution to the problem and the plate would be secured by the stantion bolts. Just a thought.
Cheers. Gerry