Who has successfully installed a clutch rod seal on Atlas or N15?

ludwig said:

The inside of the mainshaft has indeed a rough finish, that is why the slot has to be 5- 6 mm long and polished.
The idea is that the O-ring stays put, and the rod slides.
The waisted part is 4.5 mm in dia..
O- ring from an (old) Amal set screw (everyone has those lying around..)
Although 2 pieces is the better way , machining the existing rod is really no problem.
Cheap and easy, no extra nuts that can come loose or won't fit..

Click to expand...

Thanks for the specification and note on where the o-ring came from.

ludwig said:

The idea is that the O-ring stays put, and the rod slides.
<....> Although 2 pieces is the better way, machining the existing rod is really no problem.
Cheap and easy, no extra nut that can come loose or may no fit..

Click to expand...

Practical experience shows that Dynodave's solution stays put. If in doubt, application of Loctite 243 or similar should give the owner peace of mind.
Although your solution is elegant, I am not convinced it will always work as intended. O-rings need equal axial pressure in order to seal radially and to keep aligned.
Your solution does not provide alignment or pressure, resulting in a situation where the O-ring may cant or twist, allowing oil to seep past the waisted part. Maybe this is why you included some kind of felt washer outside of the waisted part?
This will need a keeper by way of a special nut, and it seems the solution has added complexity vs. the solution by Dynodave. Maybe the addition of a felt washer is required for a belt drive primary only.

- Knut

mdt-son said:

Practical experience shows that Dynodave's solution stays put. If in doubt, application of Loctite 243 or similar should give the owner peace of mind.
Although your solution is elegant, I am not convinced it will always work as intended. O-rings need equal axial pressure in order to seal radially and to keep aligned.
Your solution does not provide alignment or pressure, resulting in a situation where the O-ring may cant or twist, allowing oil to seep past the waisted part. Maybe this is why you included some kind of felt washer outside of the waisted part?
This will need a keeper by way of a special nut, and it seems the solution has added complexity vs. the solution by Dynodave. Maybe the addition of a felt washer is required for a belt drive primary only.

- Knut

Click to expand...

Maybe ask Ludwig how long it's lasted so far
And how successful it's been so you can become "convinced"

Yeah that sponge washer is a good idea. I thought about doing that but forgot last time I had the outer primary off.

Does the sponge need to be rung out once in a while?

Ludwig has a modified Commando outer cover on his N whatever it is. Very nice setup with the dry belt clutch.

Hey, baz don't wreck Knut's dystopian buzz. Doom scrollers won't have anything to read without him. Just kidding Knut. Always good to get another perspective.

Knut,

This is not something I “invented” yesterday.
The durability of it can not be judged by running time, but by the intensity the clutch is used.
I frequently ride my bikes on unpaved tracks, which is far more demanding for the clutch than just rolling down the road.
No gearbox oil comes past the O-ring.
The short rod with the O-ring is a precision fit in the mainshaft, not the sloppy fit of the std clutch rod.
The felt spacer fills the gap between the mainshaft and the adjuster bolt.. The adjuster is drilled trough, and holds a small amount of graphite grease. The felt washer prevents it from being slung around.
I also place an O-ring between the sleeve gear and the clutch locating washer.
You could also question my use of an alloy clutch centre, the use of titanium flange nuts, 1.5 mm clutch cables, etc..
From what I have read, you are a knowledgable man, and thus should be wary of using words like : “probably, maybe, I suppose,”etc..

ludwig said:

Knut,

This is not something I “invented” yesterday.
<...>
You could also question my use of an alloy clutch centre, the use of titanium flange nuts, 1.5 mm clutch cables, etc..
From what I have read, you are a knowledgable man, and thus should be wary of using words like : “probably, maybe, I suppose,”etc..

Click to expand...

Hey Ludwig, as your seal has stood the test of time and abuse, my initial concern can be put to rest. You did not reveal duration testing when presenting the design in this thread. Maybe it was mentioned in another thread.
This is good news for the community, and I may even adopt the design myself! Thank you for the clarifications.

It seems I have offended you in some way by pointing out what I considered to be weaknesses in your design of the clutch rod seal, which was the topic of discussion here.
I can't understand why. These are engineering matters, not personal characteristics. Has this forum become a site for all to applaud at the signal, as in the PRC, and where critical comments are suppressed?
Is this where we want to go? If so, I think this will be a boring place eventually.

Why should I question your choice of materials for other parts? That comment is way off the mark. If these parts work for you, that's good, and we can all take notice. People may put whatever parts they like on their bike,
it's not my or anyone's business. However, if we are to discuss general applicability, I reserve the right to make comments, as I welcome comments by others.

As for your last comment, I freely admit not being an authority in practical engineering or even wrenching, as I believe you are, and I have never pretended to be one, hence cautious use of words. We all have our expertise in different areas.
I think I understand what you are getting at, and I take your advice to heart.

- Knut

mdt-son said:

you.. when presenting the design in this thread..

Click to expand...

It was rob ss who presented it, not me.

mdt-son said:

It seems I have offended you in some way ..

Click to expand...

You did not. Sorry if I gave that impression.
It is not you, but I who should choose his words more carefully.
( or should I use smileys ? )

@ludwig & @mdt-son - I'm sorry if I have caused friction.
I was simply posting what I thought (and still believe) to be a very eloquent solution to one of the problems with our choice of mount.
Stay well & be happy.
Cheers
Rob

ludwig said:

It was rob ss who presented it, not me.



You did not. Sorry if I gave that impression.
It is not you, but I who should choose his words more carefully.
( or should I use smileys ? )

Click to expand...

Like them or loath them, Emoji’s add intonation where none exists in flat text.