Repair gear indicator switch, R 1100 GS

papa_jop · 27-08-12, 17:29

It's payback time...
I thought I should give something back to the Forum, so here's a little technical write up. Please note that wrenching is not my profession, and english is not my native tongue...

I searched up & down to find why my gear indicator was showing rubbish. Most opinions were regarding the 1150, and most reported problems involved water ingress of some kind. Well, my problems started after clutch replacement, and any potential beer spills still haven't dried out. The drive shaft needs replacement, so I might as well do it...

Firstly, forget trying your luck without removing the swing. No 9" fingers will help you on the 1100. Swing out!

The two connectors of interest are located here.

And the actual switches are located here.
The neutral switch is closest to the gear box. The gear position indicator sits piggy back on it. The are both operated by a shaft with a crescent cut-out and held in place by two small bolts (7 or 8 mm, can't remember).
After removing the bolts you can pull the outer switch straight out. A little wiggling helps. If you pull the inner switch this will happen:

Thats right... Drain the gear oil before you remove that one... There is one outer and one inner oil seal preventing the slippery black stuff from finding you rear wheel...

papa_jop · 27-08-12, 17:57

The neutral switch works on mine, so I quickly plopped it right back in...

So, whats wrong with the gear position switch? Exterior looks OK, cables look OK... That means that we have come to the part I love... Break it open & see whats inside!

These are the three major part of the switch. I heated the outer part gently with a hot air gun, and wiggled away with a small screw driver. Eventually it popped apart. Wise from experience, I knew that a shitload of small part were going to explode out in all directions, so I took some precaution on that part.

Looking at the pic, we can see that there are three floating pins (actually you don't see them as two are removed and one is submerged) connected to a center collector. These pins short circuit different tracks in the lid as they are rotated by the shaft. I found the pinout somwhere (Largiader? IBMWR?), but that was irrelevant in this case as the fault was obvious. The innermost pin is stuck in the bottom position.

I tried to shake it out... No Go.
I tried to pry it out... No Go.
I tried to freeze it with liquid propane... No Go.
Stuck! No discussion!

A close examination of that part revealed that it could easily be separated...

Like this:

Showing this:

The spring had been completely destroyed. Only small pieces remained.

papa_jop · 27-08-12, 18:05

Correct spring versus broken spring:

As beeing a man of some resource, I went to my small box of small springs to have a look...

I found a 2mm pull spring that I converted into a push spring by some elaborus magic... Yes, I pulled it out... The one on the pic was a bit too much so I made another go to resemble the original as well as possible.

papa_jop · 27-08-12, 18:28

End result:
I trimmed it to 7 mm to match the two others.

Ream the holes smooth and nice with a suitable object.

As you can see my new spring is slightly longer. Me no care!

Clean the contact part. At this stage, take notice of the little plastic tab that keys the two parts together in the right position. There is a similar slot in the other part

When you are certain where the key tab is you can lube with dielectric grease.

If you're still baffeled about this location key thing, have another look at this:

The mounting holes of the bottom part are asymetrical and cannot be turned 180 degrees without seriously complicating the rebuild...
The wire from the top part should emerge at around 45 degrees. Can you find the key now?

At this stage I coated the sealing area of the bottom part with some waterproofing gunk before reassembling. Might be good, might be overkill. Your call!
Place the rotor in the bottom part and press the top into place.

Carefully slide the switch onto the crescent shaft and rotate it to match the screw holes. Fasten loosely, connect and test!
If everything works, torque it up, route the wires and enjoy!
Don't forget to replace the gear oil if that has been drained. Check for oil leaks after some riding.

Stewart H · 27-08-12, 23:01

Thank you for sharing that, one day I may get mine to say something other than 3

thrupp · 28-08-12, 13:45

Brilliant work! Great piece of recycling. Love it!!!

Thomas

el-nicko · 13-10-12, 16:56

TOP TIP, luvit.

street_moto · 13-10-12, 17:20

Thanks for sharing

, when I got my 1100 the indicator would only show 1,3, and 5! Now four years later it works fine with just number 4 being occasionally shy

Pekkavee · 13-10-12, 19:24

Hi Papa jop
Greeting from Finland.
Tack så mycket. Jätte fint.

Thank you. Great advice for us.
I will include this into my service files.

Pekka

papa_jop · 13-10-12, 23:36

Kiitos Pekka.
Det är bara roligt att kunna hjälpa någon.
hyvä päivää, J

ChrisH Kerry · 14-10-12, 20:38

Really enjoyed reading that and great pictures too

it's the sort of thing I'd do - always worth a try!

papa_jop · 14-10-12, 21:59

Thanks!
It's always been my philosophy to try to "fix it myself".
In a case like this, the worst thing that can happen is that I will have to buy a new switch, which incidentally seems to be the recommendation most people get from the start...

Pekkavee · 17-10-12, 16:43

I ordered some springs from EBay for me in order to be ready when it happens. Now I have 165.000 km in the clock
5*2,2 mm springs
10 pieces, £3.70 GBP delivered to Finland.

Pekka