Houdini & Sachs Selector Key

[Ernie Phillips]

I need to swap out a couple of selector keys and want to avoid a complete engine teardown.  With the selector rod removed, the key will come out through the hole in the main shaft, clutch side – at least in theory.  Has anybody done this?  Here's my plan:

1.Remove clutch and external shifting hardware.
2. Loosen threaded key from rod
3.  As rod is removed insert round dowel (phillips head screwdriver) into other end of main shaft to prevent detents from coming out.
4.  Remove rod
5.  Remove old key
  - must line up slots in gears to allow key to be rotated 90 degrees longitudinally
  - use magnet and small probes to finagle key out?
6.  Install key in reverse of step 5
7.  Install rod
   - red loctite on threads
8.  Reassemble

If this doesn't work, I still have to teardown the engine.  I don't have anything to loose, do I .  Tips and suggestions welcome. I'd really like to hear from those who have performed this magic trick.  Thanks --  


Ernie P.
Chattanooga, TN

[brian kirby]

Sounds like that old kids game "Operation" where you have to use tweezers to get little parts out and if you touch the sides it buzzes. Good luck, and I hope this saves you some time.

Brian

[Ron]

Ernie,
Be sure to heat the selector key before you try to remove it.
Red Loctite is super strong without heating first.
I've never done it in the case, but I believe it requires a special tool.
RonW

[Ron]

Ernie,
I forgot to mention, you can't pull the rod out without the detent cups and springs falling out. You'll never get the back rod back together.
I think Al has the key removal tool.
RonW

[Ernie Phillips]

Brian,  Surgery is scheduled for 5PM, this Thursday. You are welcome to participate.

Ron,  What special tools?  You mean an 8 pound sledge and 15" Crescent is not sufficient?  Al B. fixed me up with the selector rod tool this morning.  thanks  



Ernie P.
Chattanooga, TN

[Lew Mayer]

It can be done. I heard about them doing it in the old days so I tried it successfully.

Lew Mayer

[Merlin]

Ernie, your method outline is 100% on the money, a philips is the ticket for sure.

Quote: Thomas Jefferson, We are all born ignorant, some work to remain that way.
 Quote:Merlin, "it is impossible to teach those that wish not to be taught".

[gooddirt]

Just split the cases! time factor is about the same and you don't have to worry about all details and shims falling out of their spots. And  if you drop something you're going have to slipt them anyway. A race bike? don't cut corners !!!![8D]

[Merlin]

Good grief, no shims or any other parts are going to "fall out", the sky might fall in before then however and no the "time factor" is not the same.

Quote: Thomas Jefferson, We are all born ignorant, some work to remain that way.
 Quote:Merlin, "it is impossible to teach those that wish not to be taught".

[Gavin Housh]

Although you may be able to perform this without spliting the cases, if you don't have a REAL Sachs key you will be spliting them soon with the selector shaft and the main shaft and several gears needing to be replaced. There are keys out there that are not able to hold up to the stresses put upon them. I have just rebuilt an engine that suffered this fate. The keys that fail have an almost black color to them. The NOS keys are a grey color with a kind of a greenish hue to them. Good luck?

[brian kirby]

Unfortunately, the reason Ernie is doing this is he already had two of those selector keys fail causing broken gears and he is replacing two more before they go.

Brian

[gooddirt]

I was wrong !!![B)]  Just removed a selector key from a old motor out of a frame. I suppose the time factor is not the same ; and if your motor is still in the bike then you will save more time . It was pretty easy most of the spent time was looking for a magnet and the fishing out the key. Should be careful of the detents does not take much to damage them and that the key is all the way down on threads .-- How long do we need to see that history lesson quote its needs a update or a new one .

[Kip Kern]

I have done it a few times.  Jeff Penton was kind enough to tell me how many years ago.  It is easy just take your time and don't get in a hurry.  I have a phillips screwdriver ground on the end to slip into the mainshaft to retain the pins and springs so they won't pop out.

[TGTech]

Ernie,
I haven't done this process in probably 35 years, but I do remember that it could be done with the small, early version of the selector keys. Honestly, I don't remember if it can be done with the larger keys.

There is one thing that must be done very properly, otherwise, you can actually stress the key that could break it.

The original Sachs keys, had differently manufactured sides. Once side of the key had a chamfer around the threaded hole and the other side didn't. The chamfered side of the key, was designed to go up against the selector rod and the unchamfered side, was to be away from the rod.

If these after market keys are built the same way, then make sure that the chamfered side goes against the rod.

The chamfer was put in the key, so that the key would clear the radius between the threaded part of the rod and the body of the rod. The other side of the key, was not against anything, so it didn't need a chamfer.

If the unchamfered side if the key was put up against the shoulder of the rod, then the key will be under stress instead of being tight against the shoulder.

Dane

[Ernie Phillips]

Thanks to everyone who contributed to a successful operation.  Christopher assisted me as 4 hands were needed at times.  Surgery only lasted about one hour.  It was too easy.  Probably just beginners luck.    

Dane,  Good point about the chamfer , but none of my keys had chamfer (I guess they are all repops.  I did trial fit key to rod and did not have any interference.

Photos of the operation:

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=diamonddons2008010.jpg

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=diamonddons2008015.jpg

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=diamonddons2008018.jpg

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=diamonddons2008028.jpg

Ernie P.
Chattanooga, TN