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
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
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
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
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
It can be done. I heard about them doing it in the old days so I tried it successfully.
Lew Mayer
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".
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]
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".
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?
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
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 .;)
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.;)
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
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
Dane
Both keys can be done but the larger ones are a lot easier as you have some more room in the mainshaft. 10-4 on the chamfer towards the selector shoulder. I had one instance where I even lost the retention cup and spring from its keeper and was able to fish it back in place and finish the job!
Kip,
Uncle Ted made a rod that was shoved into the countershaft side of the shaft to keep the detents into place until you shoved the selector rod back into the shaft.
Dane
Chamfer Revisited:
I reexamined my key collection. They all have a small chamfer (~0.030) on both sides except one. The key without the chamfer on both sides appears to be a well used OEM. I mistook the chamfer for the thread lead-in. My old eyes and lack of attention to detail ... If you are lucky enough to have OEM/NOS, chamfer goes next to the boss on selector rod. It is always a good idea to trial fit new parts. Guys, thanks for getting me back on the right track.
Ernie P.
Chattanooga, TN
Ernie,
Thanks for you valuable step by step process on this process to change shift keys. It is wonderful to have some like you add so much to this site. So many times trying to describe on this site or over the phone a process like this is difficult at best. Thank you.
Ron Carbaugh
Dane I modified a phillips screwdriver to shove through the mainshaft and push the selector rod out. Works great but you have to keep constant pressure on both to make a smooth transition. Kinda like riding a bike, don't think about it too much as you will mess up!;)
Ron, My post are self-serving. I'm just trying to learn all I can about these wonderful, weird and wacky Sachs motors. The POG is a great source to "sound-out" ideas. As usual, there is someone out there who has done it before. I do try to post in a manner that will make it easy to Search for those just joining the group. What started as a sometimes unpleasant necessity, has turned into an obsession. I actually enjoy solving the problems as much, sometimes more, than riding. And the big payoff is having the bike run cleanly the whole weekend, shift crisply, ... snag an occasional hole shot ... take the checkers. Penton has always stood for excellence. The POG models this very well. My many thanks to those who have brought it this far.
Kip, I know what you mean about constant pressure/smooth transition. I just used a large Philips and had some trouble getting the rod past the detents on the way back together. A ground rod matching the end profile of the selector rod might be the ticket. I wonder what Uncle Ted's tool looked like? I have at least one more key to swap. Wish us luck...
Ernie P.
Chattanooga, TN
I just completed another key swap and presto-chango it was a snap. I ground down a large Phillips per Kip's suggestion and it worked just fine in retaining the detents in place and allowing a smooth re-install of the selector rod. Hopefully, this will be my last one. Now, I if I can just get it to shift like a ... Sachs;)! I know, I know ... use the clutch ... every shift:(
Ernie P.
Chattanooga, TN