Selector key

[mike carr]

Waiting for my repair manual and parts list from Al, but thought I would see if anyone here can answer a couple of things, first bought a motor a few years ago, and just took a look at it, on the case is, DKW 125 6 b, has the motoplat and is a 6 speed, I thought that 6 speeds were sachs motors exclusive to pentons only.( I know that DKW and Sachs are one in the same)just never seen a DKW 6 speed but I am still knew to this.
also it wouldn't shift, split the cases and found the selector key laying in the bottom of the case, how in the hell did that happen, and how do you get it back in there? when my manual gets here that will help, thanks so much for helping me, I am running on a low budget so I have to do this motor myself, thanks, Mike Carr.OLY.

[Larry Perkins]

They were both potentially 6 speeds.  The selector key screws onto the selector rod.  Search here after you get the manual and have the selector key on and engine back together for a good article about shift adjustment.  It is easier if you have the tool that acts as the case while you dial it in.  Al sells them too.

Larry P

[mike carr]

So what I have learned is that if you fiddle around rotating the selector rod right to left to much with your fingers while you have it on the bench you can accidently un-screw the selector key and cause it to come off and then you have a problem which is what I did with another motor that I am playing around with.

[Paul Danik]

Hi Mike,

   I haven't done one for a long while, but I always used a thread lock such as Loctite on the selector key threads. Loctite had a spray cleaner that would be used on both sets of threads, the ones on the selector key and the ones on the selector rod. I remember that they also had several grades of Loctite but I always used the red which was the strongest, if I remember correctly.

   I personally would never put a selector key on without using a thread lock product, Sachs might not have done it, and the manuals may not tell you to do it, {but possibly they do}, but to me it is a no brainer.

   I was very, very fortunate to have had a dealer "back in the day" who's main line of work was building engines for sprint cars, late models, drag and race boats and any other sort of competition that needed high horsepower power plants. They actually acquired the Penton dealership so as they could pursue their woods riding hobby with bikes and parts at a discounted cost, but in short order they really got to selling a lot of machines and became known for what they could get out of the Sachs engine using the technology that they learned doing the heads on the engines I mentioned above. The reason I mention all of this is to give credit where credit is due for the concept of using the Loctite on those threads. The name of the dealership was J & D Engineeering in Valencia, Pa.

   Speaking of selector key replacement, yes, a selector key can be changed by doing the surgery through the mainshaft, but if you have a worn selector key common sence will tell you that the mating surface on second gear must be worn as well, and it is surely rounded if the edges of the key are rounded. So if it is an emergency go ahead and change that key with the engine in the frame, but if you really want to do it right replace that selector key and the gears with the worn edges.....and don't forget the Loctite...

Hope this info is helpful.
Paul

[mike carr]

Thank you Paul and Larry, it was helpful, when I put it back together I will use locktight with the selector key, this has been fun, always wanted to crack open one of these to see what made them work!

[Paul Danik]

Mike,

   "back in the day" I really enjoyed working on the Sachs engines, what was nice was that they were still relatively new and most of the ones I did were getting their first rebuild. A few suggestions if I may.

Have a spotlesssly clean work area when you pull it apart so you know that the shim you find on the bench did indeed come out of that engine.


Carefully place the gears, shims and such in proper order in an area of your bench where they won't get disturbed.  [knocked onto the floor ]


There are some thin shims that will adhear to a gear [underside] that you may not even notice at first, inspect the gears on both sides as you dismantle the engine to be sure you have every single shim and gear sitting in proper order for reassembly.


The above also goes for the shims on top of the clutch, under the
clutch including the bearings and races, and kickstarter mechanism. I also recall a shim, or possibly more that have a taper to their inner edge, take notice of their proper placement.

Also, when pulling a shaft out of the cases besure to look for any shims that stick to the case.

While you have the clutch on the bench it may pay to pull it apart and make sure that the plates are not sticking together. The issue is that during reassembly you will need to use the clutch hub to get the plates put together in proper alignment. So before you put the hub back onto the shaft and bolt it in place, do your clutch rebuild. The metal clutch plates will usually benefit from a good cleaning, I have used steel wool to get any crud off of them and get them smooth and shiny before re assembly. I always used the very finest steel wool for this job.


When you have the selector rod out you will need to reinstall it thru the little detent springs with caps, I have a selector rod that I ground to a flat taper that I insert from the opposite end of the main shaft to get those caps with springs pushed back, I then insert the actual selector rod in from the proper side and it will just push the tapered one out as it slips past those little caps. Possibly a screw driver with a flat end would also work, just want to make it easier to get the end of the selector rod past those caps with springs.

Some of this may not make sense till you are into the procedure, and possibly not even then...

Hope some of this helps.  Don't get discuraged it isn't rocket science,and everyone here will surely help if you get into a bind.

Paul

[Rick Bennett]

A number three phillips screwdriver works well to shove down the mainshaft in place of the selector rod. I have one that I ground away about half of the tip just for that job. Ditto what Paul said about all the shims. I found out when reassembling that checking end play on the crank and shafts with a dial indicator made for a better job than just using a depth guage. It will all make sense when you get a manual.
Rick

[Daniel P. McEntee]

quote:Originally posted by Rick Bennett

A number three phillips screwdriver works well to shove down the mainshaft in place of the selector rod. I have one that I ground away about half of the tip just for that job. Ditto what Paul said about all the shims. I found out when reassembling that checking end play on the crank and shafts with a dial indicator made for a better job than just using a depth guage. It will all make sense when you get a manual.
Rick

    At last another good use for those #3 phillips screw drives that we have all collected over the years!  I finally realized that they worked well for Hodaka case screws and some other things on those bikes, but other than using them for tent stakes nothings else stood out in my experience! I like having a lot of screw drivers in my tool boxes at home and at work, and would watch the Sears add for their sales on the 6 to 10 piece sets, so I have a few laying around! I almost wish I had a Sachs engine that I needed to work on just to try that out!
  Type at you later,
   Dan McEntee

[mike carr]

Thanks Paul, I will take the clutch pack apart, I have 5 of these bikes and even sitting over winter the clutch plates stick together, but riding usually takes care of it but this motor has been sitting for over 30 yrs, I have taken the clutches apart and re-assembled them with out using a detached clutch hub, but what a pain in the butt, so now I have a spare hub just for that, thanks again, going to have a big order for Al, wife is going to see my Visa amount!