lube for the speedo drive

I installed an aftermarket speedo drive unit on my Commando this year and it came lubricated with a light oil soaked into the felt ring. The unit looks and works great but I found that after a 100 mile ride it had spewed oil all over my rear hub. Are these gearboxes supposed to be lubed with oil or grease?

drc

Someone posted (can't remember where) that if you get the spray pattern on the hub that it's the grease melting from an improperly installed speedo. The friction (which shouldn't be there) heats up the grease and gives you the star pattern on the hub.

Now, if it's oil and not melted grease on your hub it could just be the excess oil from the felt seal.

Just some thoughts.

Most of my Smiths speedo drives and repro copies have a grease fitting so I always assumed grease should be used. I have seen the "star pattern" of grease on my Commando wheel cover from time to time as well but was not sure it was the speedo overheating or me putting too much grease in it. I am pretty sure I have the back wheel assembled correctly with the proper "top hat" spacer and all. Can anyone else comment on this? If my speedo gearbox is overheating, I need to find out why.

If the Spedo drive is rubbing on the hub, it will most likely heat up and the grease or whatever will get too loose and spew out. You can remove the drive and look at the hub to see if it is rubbing, there will be marks on the hub.

The post you are looking for is post18782.html Postby Ron L » Mon Mar 24, 2008 11:44 pm

Dave
69/70S

maylar said:

Are these gearboxes supposed to be lubed with oil or grease?

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The original Smiths drive boxes would normally have a sticker giving the lubricant type. This one says "SSO AVIATION G.P. GREASE OR SIMILAR". Guessing that the average motorcyclist wasn't likely to actually posess a tin of "SSO AVIATION GP GREASE" then no doubt, the drive box got a couple of pumps of whatever "SIMILAR" grease just happened to be in the grease gun at the time?

I normally pack drive boxes with Lithium (Castrol LM) grease.

I recently had to change my speedo drive, it started to show the "spider pattern" on the hub and after a while the wheel did no longer spin as freely as it should.
I was told (by a very experienced Norton club member here) that it was common that the speedo drive was incorrectly installed and that caused many failures.
As already mentioned here it is important with a fresh spacer in the speedo drive but what has not been mentioned (as far as I know) is that during assembly of the rear wheel you should apply a little lifting force under the speedo drive before you start to torque the rear axle. If you install the parts without applying any torque you can feel that the speedo drive can be lifted (actually both up-down and forward-backward) a littel bit, you have a radial clearance there, and you should try to lift the speedo drive to end up with it in the middle, leaving equal amount of radial clearance around, before you apply any torque to the rear axle. By doing this properly you will extend the life of the speedo drive.

Regards,
Per

I need a new speedo drive and was wondering where you bought yours. Waldridge lists two in their catalogue, the less expensive one coming from India. RGM lists one at the best price but I know nothing of the quality. Any information would be appreciated. T.T.

I got mine from Old Britts, they didn't list where it came from.

I got mine from RGM, seems to be ok but I guess time will tell.

Regards,
Per

As long as we are taking about speedo's and lube, any comments on lube for the speed and tach cables?

Hi , everybody , I cannot afford as said in manuals ten different sort of grease , so I had bought copper grease , which is a premium but I used it everywhere and in the speedo AND in the cable, it seems to resist pretty well to any high temp , plus as it was supplied in a tube , you can use it sparingly , instead of throwing buckets of cheap stuff which finish everywhere, and mainly where you don't want it: your hand, the ground , the tyre, .......let you appreciate the neat guy I was before!!!!!!!!

Well the gearbox I have has the same sort of grease zerk that the original Smiths unit has, and it doesn't fit my grease gun. I think I'm gonna soak it in solvent and remove the oil and replace the zerk fitting with something that fits. I have EP chassis grease in my gun that I use for automotive tie rods and such, that'll probably work.

ttbiker said:

I need a new speedo drive and was wondering where you bought yours. Waldridge lists two in their catalogue, the less expensive one coming from India. RGM lists one at the best price but I know nothing of the quality. Any information would be appreciated. T.T.

Click to expand...

I think all of the repro speedo drives are made in India or Taiwan now aren't they? They all seem to be about the same price so I assumed they were all coming from the same place. I've bought several from different sources and the quality seems much lower than the original Smiths. I have since bought several Smiths drives on eBay which was a bit of a crap-shoot. However, the ones I got were significantly and all have been in very good condition.

calbigbird said:

As long as we are taking about speedo's and lube, any comments on lube for the speed and tach cables?

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I use white lithium grease. Stop the grease about a foot from the top or it will work its way into your instruments and foul them up

I use Mobil 1 synthetic grease, it has a fairly high melting point so it dose'nt melt and make a mess, I also use it on the drive cables. My MKIII has 72,000 miles on it with the orignal speedo drive and insturments, the orignal drive cables have been replaced once.

Ken G.