I think my drive shaft has a leak.

[Pressureangle]

1 hour ago, audiomick said:

I've been thinking about that. Would it be really tragic if that end of the shaft wasn't air-tight? Phil wrote that the bung in the end is just a plate staked into place. I dare say that isn't really air-tight even when it is new.

I'll be taking mine out again to have a close look at it, but I'm inclined to think that if I don't rely on the grease nipple to lubricate, i.e. take it off every year or two and grease it dismantled on the bench, then it shouldn't really matter too much if that bung doesn't seal 100%.

Or am I overlooking something?

No, I think you're right; if you grease it manually and annually, the bung is really just a dust shield anyway.

[Lucky Phil]

6 hours ago, audiomick said:

I've been thinking about that. Would it be really tragic if that end of the shaft wasn't air-tight? Phil wrote that the bung in the end is just a plate staked into place. I dare say that isn't really air-tight even when it is new.

I'll be taking mine out again to have a close look at it, but I'm inclined to think that if I don't rely on the grease nipple to lubricate, i.e. take it off every year or two and grease it dismantled on the bench, then it shouldn't really matter too much if that bung doesn't seal 100%.

Or am I overlooking something?

I dont know whether sealed is optimal or not I've never use the grease nipple and just lubed it by hand as pressureangle suggested. My bike doesn't do lots of miles though. I would assume that any time the end is filled with grease and it's compressed grease just forces it's way past he oring? not sure.

 

Phil 

[audiomick]

17 minutes ago, Lucky Phil said:

 I would assume that any time the end is filled with grease and it's compressed grease just forces it's way past the O-ring?

That is what I was expecting, i.e. I expected to see grease come out of the join between the two parts of the shaft as an indication that there was enough grease in there.

 

From my very reliable source I have been informed that (a) normally, excess grease does indeed come out past the O-ring, and (b) when one is greasing the spline with a grease gun and grease comes out of the join, that is already too much.

According to my source, one or two pumps of the grease gun is enough. When I think about it, he's right. There is not much space in there.

During the course of my experimentation, I pumped some grease into the dismantled end of the other shaft that I have. Two pumps put in enough to, I reckon, more than fill the available space.

It might even be one of those fabled "less is more" situations.