Tacho cable oil leak

[Fat Dell]

Hi guys

1961 BSA A10 Super rocket.
Another oil leak I’m trying to eliminate is where the Speedo cable goes into the housing / drive.
The oil is actually leaking out from around the cable.
Can anyone please advise whether there’s supposed to be an o ring type seal internally here?
The drive looks to have a micropscopic  o ring on it also. Unsure if this just may be the problem, letting oil through and needing replacing?…Almost looks like if that particular I ring needed replacing, the drive it’s on may need replacing fully as it’s so small?
As I say, I’m not sure so taking a guess or three. Cheers all.

[JulianS]

That is an A65 type rev counter drive adapter now supplied for the A10 as well. Fits the A10 Ok just find a suitable O ring to fit in the recess. This works better than the rather flimsy O ring on the drive shaft. Current production shafts dont seem have an O ring or scroll.

The original A10 type did not have the recess.

Photo show original A10 type taken from a 1962 Rocket engine, the early shaft has O ring but no scroll. BSA added the scroll to try to keep the oil in.

[Fat Dell]

Thanks for that!
Great bit of info, and I’ll proceed with fitting an o ring now. Cheers

[Rex]

I've never managed to cure the drip from the speedo cable on my plunger A7 either, a set-up entirely different from the one shown in the pics.

[Swarfcut]

 Don't connect the speedo to that tacho drive..... Speedo Drive is from the bottom of the gearbox, and as we all know there is no way of preventing oil seeping down the inner cable. The drive spindle has a scroll, later alloy spindle sleeves have an O ring, but the whole design is flawed. A good outer cable with an undamaged outer casing prevents the drips, and that's about the best we can hope for.

 Swarfy.

[Fat Dell]

Thanks Swarfy.

Just to clarify…are you suggesting the best course of action would be to replace the cable itself and the casing that has the insert?
Thanks again

[Rex]

I'd examine it first if I were you. My cable is new, undamaged and with sealant around the crimp connection and it still leaks...

[KiwiGF]

I cured the leak from the cable on my ‘56 using “self curing rubber tape” would around the end of the cable.

[Fat Dell]

I’ll put an o ring in and will see how that stems the flow before replacing cable.
It’s a cheap easy (potential) solution, which is quick to action, so will try that first and go from there.
I’m not looking at cutting any corners of course, but this certainly seems work a crack.
I will look into replacing the drive casing as suggested by Swarfy also most likely, pending the results. Cheers

[chaterlea25]

Hi All,
Some confusion in this thread  between the speedo and rev counter drive
When I first got my SR on the road, I found oil on the front mudguard
The rev counter drive leaked and the oil was "wound" up into the rev counter by an incorrectly spiralled inner cable
My eventual cure was to make a new drive housing for the engine end containing two miniature sealed bearings
No more leaks

John

[Fat Dell]

Hi.
Yes, thanks you are correct.
I’ve stated the wrong thing to start with I think.
It’s the rev counter guys.
Sorry for any confusion and thanks again for everyone’s input

[Tomcat]

I cured the leak from the cable on my ‘56 using “self curing rubber tape” would around the end of the cable.

I used heat shrink tubing to seal the cable outer.