Speedo cable wrapped around axle

CanukNortonNut said:

I've seen it on my mates commando. Spun and pulled cable at a rally. My drive disintegrated or rounded out so I didn't lose the cable as his did. Mine, It just stopped working during a NYNO rally. Part of the maintenance. Shit happens.
cheers,
Tom

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Clearly they weren't designed to last 50 years, so we should count our blessings.

gortnipper said:

Clearly they weren't designed to last 50 years, so we should count our blessings.

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Aye, Count our blessings.
Ive got a Omega seamaster de ville automatic wrist watch mechanical built in the late 60's and it still keeps the time. A clean and wash every ten years and it keeps working. We lost our ways as engineers in the 70's.
Anyways I'm ranting off topic but that's how i feel.
Swooshdave you got some maintenance to deal with.

gortnipper said:

Clearly they weren't designed to last 50 years, so we should count our blessings.

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Very true.

And applies to the whole bike !

My Samsung TV lasted latest 51 weeks.... no user service parts available
i hate this throw away world

olympus said:

My Samsung TV lasted latest 51 weeks.... no user service parts available
i hate this throw away world

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You bought the wrong one, Malcolm



Thanks to Viz as always

Off Topic i know Brett... this brightened my dull Tuesday.. thank you

The reason why the speedo gearbox wears out/ seizes up is because the little grease nipple that is fitted doesn't allow grease into the gearbox! It is not the usual 'Hydraulic' grease nipple (Or 'zerk' to friends over the pond) So when the pathetic little pump action grease pump is used and the grease comes out at the nipple you think that some has got into the gearbox anyway. Not so, there is a little spring and ball fitted in the grease nipple that nicely blocks the way... Pick the spring and ball out of the nipple to allow grease to enter the gearbox.

Or remove the supplied nipple, fit a 'hydraulic' style grease nipple and use a proper grease pressure gun. Do not over grease the gearbox, you can easily push grease into the brake drum .
Edit. just realised I,ve just spoke a bit of bollocks. The speedo gearbox isn't next to the brake drum.!,

swooshdave said:

Those don’t explain why after ten years it decides to pack up. If it hadn’t been shimmed correctly it wouldn’t have lasted this long.

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But you aren't taking into account that parts wear (and in this instance the speedo drive gearbox can distort so causing enough friction to melt the grease) so just because it was right ten years ago doesn't mean it's going to remain that way.

The threads at least give some insight as to why it happens and what can be done to remedy the situation short of buying a new drive gearbox. This post by texasSlick in one thread being a prime example of how to correct the distortion https://www.accessnorton.com/NortonCommando/shim-on-speedometer-drive.26779/post-401729

Grease does not stay where it is needed inside the Speedo gearbox. It migrates to the periphery where it does no good.
This was explained in another gearbox thread, and told what grease should be used.

Slick

dobba99 said:

Or remove the supplied nipple, fit a 'hydraulic' style grease nipple and use a proper grease pressure gun.

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I have a proper grease gun. Are the nipple's threads the same as what I'd find in a US hardware store (or Amazon)?
Like these:

Amazon product ASIN B0020MRLV2

maylar said:

I have a proper grease gun. Are the nipple's threads the same as what I'd find in a US hardware store (or Amazon)?
Like these:

Amazon product ASIN B0020MRLV2

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Just measured the nipples thread in one of my spares,= 2BA
at the same time i measured the pressure it takes for the pathetic pump action grease gun 'thing' to overcome the spring loaded ball in the standard nipple. it takes at least 160psi to open the nipple. That and the fact that the gun connection relies on the seal between the conical seat and the nipple ensures that NO grease gets into the gearbox and it just squeezes out and make a mess.
You can get a better result by taking the nipple out and pumping grease into the hole itself, will make a mess still but will get grease in there. then just use the nipple as a plug.

So even if you grease it you can't grease it. Gotcha.

maylar said:

I have a proper grease gun. Are the nipple's threads the same as what I'd find in a US hardware store (or Amazon)?
Like these:

Amazon product ASIN B0020MRLV2

Click to expand...

You can use a 10-32 nipple in place of the 2BA and it will thread right in, just be careful as it may be slightly tight.

gortnipper said:

You can use a 10-32 nipple in place of the 2BA and it will thread right in, just be careful as it may be slightly tight.

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Double check the length of the threaded portion regardless of 2BA or 10-32 and make sure it doesn't foul the ring gear in the speedo drive. Original nipples seem to have shorter threaded portions than modern replacements. Nothing that can't be fettled though.

FWIW, be careful when using a standard grease gun fitting. The ones I got from NAPA were slightly longer than the stock ones and got caught in the horizontal gear. I spaced it out with a small washer.

I'm guessing the grease wore out. In the meantime I'll just run without the speedo. It's a race bike, right?

looks like it got chewed! Lots of metal filings there.

Here is my spin on it, I am still running my original speedo drive and original cable and after 46 years still works good, I don't grease by the grease nipple but everytime the wheel is off for a new tyre or wheel bearing maintenance I give the drive a good clean in kero and once clean I give the drive a spin with my fingers when it feels right I put grease on the drive with my fingers and work the grease into the gear box, I don't over do it with the grease just enough to keep things lubed, I makes sure the 2 blocks that mount to the wheel is in good condition before refitting, I also lube the end of the cable that goes into the drive, I also put a dash of grease where it mounts to the speedo, not to much just enough to lube, to much grease is not good, I think my speedo cable has only been lubed twice in all these years its the ends that have problems mostly and is normally where they break.
Its just part of any maintenance anything that has moving parts in it needs to be cleaned and relubed not just pumping grease into it, old grease can go hard if to much is in there, working as a T/A to maintenance Fitters for over 20 years I have seen bearing that have over heated from over greasing and not having the bearing cleaned out of old grease and new grease added, old grease does go hard from heat over years of use even if new grease has been pumped in.
Most do there maintenance like oil changes regularly but sometimes over look the small things that also need to be cleaned and relubed, same as sealed wheel bearing or any sealed bearing for that matter will last a life time if you pull the seals and give them a good clean and repacked with fresh grease, its all about general maintenance, look after your parts and they will last and if you ride in a wet place then its even more important to do regular maintenance sooner than later.

Ashley

Pry the lid off and show us the worm and ring gears so we can see the true damage.

Put it in a container and bath it with kerosene or brake clean . Put a magnet in there and that should tell you some type of story.