Speedo bounces

[terryg]

RoyC - thanks for the link to Gagg and sons. I thought that name had died some years ago.

So Nottingham is now well endowed with chronometric instrument specialists.

Perhaps anyone putting work that way can find out and tell us more of the story.

[JulianS]

This bracket fits the studs on bottom of speedo body and bears on the nacelle to hold it in place. Just undo the nuts and cable and it will come out.

[berger]

terryg as far as I know gags have been around a very long time mainly concentrating on bsa spares, a few years ago I went over to buy an original 6 spring clutch middle because the ones bantam john kept wanting to sell me [crap soft imports]got destroyed very quickly.i was very lucky that day because ba@t@rd john had not long cleared out all their stock. I got the part and just had to straighten one stud, while I was there they told me they were just going to work on rev counters ,speedos cables etc, they repaired my 3to 1 tacho 10years ago[still good]. I think the main reason for down sizeing was an age thing... yep we all age very quickly after 50 in my opinion

[terryg]

Berger - I have bought from Gagg and Sons too. A long time ago.
Russell at Chronometrics told me their main stock had gone to Bantam John. Perhaps 6-8 years ago??
I may be remembering wrong but I think Russell was, at one time, repairing clocks for Gaggs. That would have been when they were still selling BSA parts - so also way back.
Apologies for the thread drift!

[RoyC]

This bracket fits the studs on bottom of speedo body and bears on the nacelle to hold it in place. Just undo the nuts and cable and it will come out.

Good one Julian, as simple as that eh. Looks like me braving the cold this week. 
Roy.

[RogerSB]

Roy, if it's any help here are photos of my Chronometric speedo before I sent it to Philip Woods to refurbish.

http://www.chronometricspeedos.co.uk/index.html

It was also erratic and sometimes the needle would shoot up to 80 mph and stick there even when I was only doing about 10 mph and sometimes even when stopped.  It turned out a previous owner had squirted oil inside it and gummed it up. You can see the mucky oil on the central cogs in the photos. The pillar sticking up on the left (photo Speedo 3) is what the flexi trip shaft attaches to by a very tiny split pin through the hole.

If yours is that oily it may be worth washing it out with petrol, so it'll evaporate afterwards. Be careful though, as I don't know if petrol would effect the printed numbers on the speedo face.

[RichardL]

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,

Sorry for the delay. Here is the document I was thinking of, but I think you might already have it, or maybe not, since it refers to "Jaeger, the original inventers. http://www.wdbsa.nl/Jaeger-Chronometric-Overhaul.pdf


Then, there is this description for fixing a jerky needle: http://www.thevincent.com/vininst.htm

Jerky Speedo Needle:  First,  remove cable now. No more operating the speedo until this very easy fix. This peculiar glitch  is quite simple and only requires that the speedo be cleaned and re-lubricated to function  normally.   Remove unit from its bracket  atop the forks.  Remove the screws that enter from the rear of case.  Carefully, wearing a leather glove for grip, unscrew the chrome bezel.  If dead resistant to turning, dribble a bit of light oil (WD-40 or 3 in1) into its threads, let sit  face down for the oil to ooze down into the threads.  Retry to unscrew the bezel.  The  reset  knob is secured to its shaft with a tiny
screw which must be removed.  Ease the guts out of the case while pressing  knob shaft inward.  Lay face down on a  soft cloth being careful of the needle.  Using a spray can of contact cleaner like  PJ-1, spray off all gears and everything that moves.  This step will remove the dried greasy lubricant applied with original assembly.  Spray around and in all sides.  Your targets include all springs, clock-like bits, vibrating bars, etc.  Be careful  if the round wheel numbers get soft and lose shape.  Work quickly !  With a  controlled easy air blast - gentle now,  dry off,  blowing to evaporate the solvent everywhere.  Obtain an
aerosol can of  light gun oil or instrument oil,  3 in 1 will do too.  Spray  lightly over all of the mechanism and  moving parts.    Turn over and wipe clean the face and needle and  number wheels.   Leave draining on absorbant paper. Gently remove any loose droplets to be seen.   Clean glass and face. Reassemble speedo as was before.    Pull cable inner wire out its open end and clean and oil.  Refit as before.   Regrease the lower drive box  and barely grease the inner gear on hub.   Sid Biberman  05/01/01.


Hope this helps in some way.

Richard L.

[RoyC]

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,

Sorry for the delay. Here is the document I was thinking of, but I think you might already have it, or maybe not, since it refers to "Jaeger, the original inventers. http://www.wdbsa.nl/Jaeger-Chronometric-Overhaul.pdf


Then, there is this description for fixing a jerky needle: http://www.thevincent.com/vininst.htm

Jerky Speedo Needle:  First,  remove cable now. No more operating the speedo until this very easy fix. This peculiar glitch  is quite simple and only requires that the speedo be cleaned and re-lubricated to function  normally.   Remove unit from its bracket  atop the forks.  Remove the screws that enter from the rear of case.  Carefully, wearing a leather glove for grip, unscrew the chrome bezel.  If dead resistant to turning, dribble a bit of light oil (WD-40 or 3 in1) into its threads, let sit  face down for the oil to ooze down into the threads.  Retry to unscrew the bezel.  The  reset  knob is secured to its shaft with a tiny
screw which must be removed.  Ease the guts out of the case while pressing  knob shaft inward.  Lay face down on a  soft cloth being careful of the needle.  Using a spray can of contact cleaner like  PJ-1, spray off all gears and everything that moves.  This step will remove the dried greasy lubricant applied with original assembly.  Spray around and in all sides.  Your targets include all springs, clock-like bits, vibrating bars, etc.  Be careful  if the round wheel numbers get soft and lose shape.  Work quickly !  With a  controlled easy air blast - gentle now,  dry off,  blowing to evaporate the solvent everywhere.  Obtain an
aerosol can of  light gun oil or instrument oil,  3 in 1 will do too.  Spray  lightly over all of the mechanism and  moving parts.    Turn over and wipe clean the face and needle and  number wheels.   Leave draining on absorbant paper. Gently remove any loose droplets to be seen.   Clean glass and face. Reassemble speedo as was before.    Pull cable inner wire out its open end and clean and oil.  Refit as before.   Regrease the lower drive box  and barely grease the inner gear on hub.   Sid Biberman  05/01/01.


Hope this helps in some way.

Richard L.

That is brilliant Roger, doesn't sound as difficult as I was imagining.
The  second article is very easy to understand and has given me a little encouragement to have a go.

Roy.

Edit - Sorry. Not Roger, should be, That is brilliant Richard. 

[JulianS]

Roy

There is not much space to direct any spray cleaner into the mechanism without removing it from the zinc alloy frame. The structure shields it and it is hard to keep it off the drums of the oddometer and trip.

Same goes for spraying any lubricant inside - it is a bit haphazard and it is difficult to direct it and over lubrication is the cause of some chronometric problems.

My view is that it is best to follow the guidance in the first article.

Getting the mechanism out needs care - removing the needle can be difficult and it is easy to bend it (been there done it).

[Bsareg]

Don't know if Smiths changed the method of printing the dial, but I've had a couple of speedos where the digits are ruined very easily. Try not to touch the dial when the fluids are around.

[RogerSB]

Roy, forgot to mention, I've read that oil can gradually over time work up the inner cable from the gearbox speedo drive shaft and bush if even slightly worn and if it reaches the top of the inner cable it can then enter the speedo. Check how oily your inner cable is at the top. As Richard's piece says clean it and lightly oil. I lightly oil mine with machine oil (ie 3 in 1).

[duTch]

 Three things here;
 1> not a biggy for all except RichardL, but Roy, unless I'm cross-eyed, it's Richard who you erroneously attributed to Roger
2> when I had my speedo  redone last year, I was told there's 60+ lubrication points requiring something like a dozen different lubes needed

3> How about some grease down low in the cable, which should inhibit oil from driving up- as far as I recall and it's been a while but I think books say grease to ~6" short of the top- which is difficult when the inner goes in the grease comes off from top down

[Rex]

Don't know if Smiths changed the method of printing the dial, but I've had a couple of speedos where the digits are ruined very easily. Try not to touch the dial when the fluids are around.

Absolutely. The dial and digit drums's markings come off very easily unlike fingerprints, which don't!

[RoyC]

Well, got it out ok and the chrome ring came off very easily with two strap wrenches.
I could hardly make out some of the numbers, they had so much patina on them.
After removing the needle (came off easily) and the dial, I got some petrol in a dish and with a cotton wool bud soaked in petrol gingerly wiped one of the worst soiled numbers, it came up a treat, so I did all of the numbers, no sign of the numbers being damaged. 
I then put the whole workings into the dish of petrol and gave it a good shaking.
Took it out and checked it, all OK, so put it back into some clean petrol to soak for a while then gave it another swish around in the petrol.
I then let it drain onto a piece of newspaper before giving it a blow with a hair dryer.
I cleaned the dial with some kitchen towel with a drop of petrol on it, dried it and gave it some polish.
I cleaned the needle with some petrol on a cotton bud, de-greased it and sprayed it white.
Then got some 3 in 1 oil and oiled the workings, left it on it's side for excess oil to drain out.
I will put it back together tomorrow.

I have got a new cable coming from Feked,

Thanks chaps for all the advise, appreciate it. 

Roy.

[RoyC]

Taken the liberty of using Roger's photo.
Should the part that houses the trip gear be wobbly ?