Author Topic: Speedo bounces  (Read 2388 times)

Offline RoyC

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Speedo bounces
« on: 10.02. 2018 13:22 »
First run on the bike.
Speedo bounces all over the place, not a hint of how fast I am going.
Do I need a new speedo ?

Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline Greybeard

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Re: Speedo bounces
« Reply #1 on: 10.02. 2018 13:29 »
Could it be a whisker of inner cable catching? I'm sure you already know, chronograph devices do not move smoothly.
Greybeard (Neil)
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A Distinguished Gentleman Riding his 1955 Plunger Golden Flash

Offline RoyC

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Re: Speedo bounces
« Reply #2 on: 10.02. 2018 13:40 »
Could it be a whisker of inner cable catching? I'm sure you already know, chronograph devices do not move smoothly.

It will be around 0 to 10 mph then suddenly bounce up to around 40/50 then back to 10/15 and so on, while all the time i'me doing around 25 mph, not a hint of the actual speed.

A new cable would be first thing to try then ?
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Speedo bounces
« Reply #3 on: 10.02. 2018 13:58 »
Could it be a whisker of inner cable catching? I'm sure you already know, chronograph devices do not move smoothly.

It will be around 0 to 10 mph then suddenly bounce up to around 40/50 then back to 10/15 and so on, while all the time i'me doing around 25 mph, not a hint of the actual speed.

A new cable would be first thing to try then ?
I've just ordered a new cable from Feked, got to be cheaper than a new speedo at this stage.
My bike is a 1958 A7SS
Staffordshire UK

Offline Rex

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Re: Speedo bounces
« Reply #4 on: 10.02. 2018 15:08 »
You could have tried cleaning and lightly regreasing the old one first...

Online RichardL

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Re: Speedo bounces
« Reply #5 on: 10.02. 2018 15:18 »
A new cable is a minor investment and not a bad thing, but my guess is clock innards need cleaning and proper lubrication. There are guides to this that can be fairly easily found if you care to go after it yourself. Let me/us know if you need a link.

Richard L.

Offline worntorn

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Re: Speedo bounces
« Reply #6 on: 10.02. 2018 15:53 »
It might come out of it with use.
My SR tach would bounce up to 8 k rpm, drop back to 3 then stick at 6, all while cruising along at a constant speed.
I was about ready to send it off for refurbishment when it started to improve.
Now it almost works properly, getting a little better each ride.

Glen

Offline RoyC

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Re: Speedo bounces
« Reply #7 on: 10.02. 2018 15:54 »
A new cable is a minor investment and not a bad thing, but my guess is clock innards need cleaning and proper lubrication. There are guides to this that can be fairly easily found if you care to go after it yourself. Let me/us know if you need a link.

Richard L.

As long as there is no stripping the innards out of it I will have a go at cleaning it.
Could you point me to the article your referring to please ?

Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Speedo bounces
« Reply #8 on: 10.02. 2018 15:58 »
It might come out of it with use.
My SR tach would bounce up to 8 k rpm, drop back to 3 then stick at 6, all while cruising along at a constant speed.
I was about ready to send it off for refurbishment when it started to improve.
Now it almost works properly, getting a little better each ride.

Glen
Thanks for that Glen.
I will install the new cable and see how it goes between now and the warmer weather.
Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline A10 JWO

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Re: Speedo bounces
« Reply #9 on: 10.02. 2018 16:49 »
I use Gagg and Son to service my speedos, they are on the net or advertise in OBM.

Offline Greybeard

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Re: Speedo bounces
« Reply #10 on: 10.02. 2018 17:07 »
I was very happy with Chronometric Services:
https://www.a7a10.net/forum/index.php?topic=11439.0
Greybeard (Neil)
2023 Gold Star
Supporter of THE DISTINGUISHED GENTLEMAN'S RIDE https://www.gentlemansride.com

Warwickshire UK


A Distinguished Gentleman Riding his 1955 Plunger Golden Flash

Offline terryg

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Re: Speedo bounces
« Reply #11 on: 11.02. 2018 08:02 »
As far as I know  Chronometrics.co.uk (Russell Smalley) IS what's left of Gagg and Sons.
Many recommendations to be found on the forum.
Terry
'57 'SR', '59 SR, '63 RGS

Offline RoyC

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Re: Speedo bounces
« Reply #12 on: 11.02. 2018 10:59 »
As far as I know  Chronometrics.co.uk (Russell Smalley) IS what's left of Gagg and Sons.
Many recommendations to be found on the forum.
They both have a website. 
http://www.gaggs.co.uk/html/speedometers.html
 
http://www.chronometrics.co.uk/html/speedometers.html
My bike is a 1958 A7SS
Staffordshire UK

Offline duTch

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Re: Speedo bounces
« Reply #13 on: 11.02. 2018 12:45 »

 Mine did a bit of a bounce the other day too- almost off the dial, but I don't *remember* doing 140 (Mph)  *eek*

 A little nut had fallen off the end of the doodadometer shaft and jammed itself where it wasn't invited- I think all ok now
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
Australia

Offline RoyC

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Re: Speedo bounces
« Reply #14 on: 11.02. 2018 15:46 »
At a quick glance, I can't see how to get the speedo out and there;s nothing in the service sheets about it.  *conf2*

Roy.
My bike is a 1958 A7SS
Staffordshire UK