Lubrication and cleaning speedometer

Hank Dymale · Post by **Hank Dymale** » Wed Feb 03, 2016 8:41 pm

I am a new member to the 305 forum. Last fall I hauled my 1967 Cl77 back from Albuquerque to Wisconsin. I am presently rebuilding the bike from parts. My brother tore it apart 45 years ago and it has been in parts ever since. I am making good progress thanks to the posts on this forum. My question is how to lub and clean my speedometer. I know it is in good shape but I would like to check it out. I know there are some posts on this forum on how to do this, but I must be stupid because I can't find them. Would appreciate some help on locating this post (I think by G-MAN). Thanks.

G-Man · Post by **G-Man** » Thu Feb 04, 2016 9:06 am

Hardest part is getting the bezel off the speedometer./ Just pry it up carefully with sucessively large screwdrivers.

After that just clean everything and re-lube. Don't put any cleaner or lube between teh two parts of the magnetic drive drum as it needs an air gap.

The needle will come off with a couple of blunt flat screwdrivers with some cardboard underneath to protect the dial.

G

OldScrambler · Post by **OldScrambler** » Thu Feb 04, 2016 2:32 pm

Putting it back together (crimping) is the hard part............be sure to keep the face of the speedo upward to prevent any excess lube from staining it.

If your unit is fairly clean............I have had good success with Teflon Spray applied at the drive-sleeve while holding the unit somewhat face-up.

Tip...........When you get the bike together be sure your cable is lubed inside of the sheath at the bend near the axle-drive. If you notice your speedo-needle jerking....STOP....disconnect the cable to prevent breaking the speedo............its usually the rusted cable that is un-raveling.

PS........you and your bike are very welcome to WISCONSIN

conbs · Post by **conbs** » Mon Feb 08, 2016 8:20 pm

I agree with G that the hard part is getting the bezel off without tearing the brass. Nice and slow is the way to go.

There are 3 lube points. Under the needle and the bushing in the back where the cable attaches are the two easy ones. The third, however is the most important. It is down inside the magnetic drum where the needle shaft turns within the lower shaft that the cable spins. That pivot point must turn very freely. G is right that you can't leave any lube in the cup. But, I have gotten away with putting a good bit of lube in the cup and letting it sit overnight and then turn the cup on its side to let ALL the excess lube drain out. If any is left to create drag between the two cups or even the shafts you will have trouble. The alternative is taking the speedo drive completely apart and then you risk ruining the little "watch" spring. It is calibrated so you need to be really careful not to tweak it when you have it apart.

I found one repair shop (I think in GB) that listed speedometer faults and probable causes. He uses synthetic oil for lube, saying: "Use 1 Mobeus D3 (synthetic clock oil - stupidly expensive), 2 synthetic bicycle chain oil 3 machine oil to lube speedo. Use Castrol L.M. or ESSO TSD 119 grease to lube cable. I bought some synthetic oil on eBay. I think it was "Liberty Oil" It has worked well for me.

I have had pretty good luck putting the bezel back on by putting the parts of the speedo in a vice with a piece of plywood over the bezel. Gently squeeze until the glass, bezel, etc. are seated firmly against the case. DON'T BREAK THE GLASS!! I then use a large flat-faced punch to get the bezel bent back flat against the case. Release and turn the speedo as necessary to work around the bezel. Once again, nice and slow is the way to go.

I hope that helps. Report back how things turn out.

G-Man · Post by **G-Man** » Tue Feb 09, 2016 3:04 am

Conbs

Great advice.

G

Hank Dymale · Post by **Hank Dymale** » Mon Feb 22, 2016 11:31 am

I finally took the plunge and tore into the speedometer last night. Everything went according to plan and according to the help of forum members. My CL77 speedo is in good enough shape and all it needs is a good cleaning and lubrication. I would like a few suggestions on how to properly lub the lower drum bearing without causing the problems that some members have mentioned. I can see where over lubrication can cause quite a mess with this delicate mechanism.

I plan on cleaning all worm gears of old crusted on grease and then (using a light oil like Rem Oil) to lightly lub the 2 shaft bearings. I then plan on placing a touch of white lithium grease on the cleaned worm gears. I am, however, still a little confused on the best way to lub that lower bushing. Your help would be appreciated. Like one member mentioned, by rebuilding my own speedo, I am a few bucks closer to purchasing a e-ignition system

Thanks again for all your help. My rebuild would not have gone as smooth without your help and of course the help of Mr. Bill Silver.

If I can ever figure this system out I would like to include some pics.

Snakeoil · Post by **Snakeoil** » Wed Feb 24, 2016 10:54 am

The key to having a well running speedo is getting the gaskets and seals done properly or the first time you get caught in the rain is going to dump water into the works.

When I did mine, the stack up of gaskets is complicated and took some doing. I ended up building up the sealing system using hand cut gaskets and black silicone. I did it in stages so it came out neat. Last step was sealing it to the bezel and then crimping the bezel.

regards,
Rob

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