Neutral switch-gear indicator

[klockea]

Folks,
I'm the owner (3rd) of a '97 RT with 59,000+ miles on it. Purchased with just over 47K. It has been a labor intensive purchase right up to the current day. This spring I decided I had to do this spline lube procedure. After getting everything apart and lubed, I also decided to install a new clutch because I didn't want to revisit the entire procedure in another 10-20k. During reassembly I installed a new neutral light switch because the original one was working only occassionally. Everything went well until the first ride. Gearbox leak around the new switch/o'ring. I spoke with a tech person at Bob's and was told that for my year RT a seal was also part of the new switch install procedure. So I ordered another new o'ring and companion seal. This week I took the entire back end off, again, and I just tried to install the new seal and o'ring. Spent 30 minutes trying to install the switch again and I have given up. Not something I usually do. It will not seat all the way with the seal set in to the face of the switch. The o'ring design is something I can't even believe a real engineer would do.
To be polite about the entire BMW ownership experience, I'm extremely disappointed and frustrated with much of what I see. Some of it is great, some is poor.
I would very much appreciate it if someone who REALLY knows the answer to getting this switch/seal/o'ring situation corrected would converse with me so I can get this thing back on the road. I have a 72 mile round trip commute every day for work and would like to start riding to work again and stop consuming so much
$3++ dollar a gallon gas. Thanks in advance.

[Andy VH]

I think this is the switch you're talking about? I have a 94 R1100RS, which should have the same tranny as your 97.

I did a couple clutch jobs on my bike and had the tranny out twice before for internal bearing failures (don't worry, that was updated in the 96 model).

But, I have had no problems with sealing around the switch, and I did nothing special with mine, nor did I add any additional seal.

I wonder why you couldn't simply use some Permatex Form-a-gasket type product on the switch seal area? Don't even bother with the additional o-ring. Even Yamabond or Hondabond (both excellant sealant products) may be a good alternative.

I'd bet if you just take out the rear wheel and swingarm you'll have all the access you'll need to get at the switch. I know, getting the rear drive hub and swingwarm off is enough of a big project itself.

[klockea]

Andy,
Thanks for the response. That was going to be my next alternative. I'm getting real good at taking the back end off this thing. It is currently all apart for the second time this spring. This time ONLY up to the tranny. Sealants are great products.

[AntonLargiader]

It will not seat all the way with the seal set in to the face of the switch. The o'ring design is something I can't even believe a real engineer would do.
I can't tell what difficulty you're having, but if the switch doesn't seat fully you are probably not engaging the stub end of the shift drum (that's what's sticking out there) into the notch in the switch. Meaning that you won't have correct switch function. If you're considering the use of sealant to overcome that, you are just going to get into a mess.

If you can turn the switch so that it is in neutral (continuity between the wires) and the bike is in neutral, all should line up and it'll fully engage with a tiny bit of wiggling.

As for the O-ring, well, I've never had one leak so I can't say they did a bad job there. And I've reassembled a lot of these trannies.

Now, on re-reading your post, it seems that maybe you have installed a second seal into the switch? It probably came with one installed in it. Could that be the problem? I can definitely see that keeping the switch from going fully home in the bore.

[klockea]

I am going to work on it again today. The first time I reassembled everything the switch worked fine. Neutral light functioned as it was supposed to and the gear indicator(which I presume is the second half of the switch which is original) is ok. It's obvious they both have to be oriented together to line up with the flat on the the shaft. Both bolts seemed to tighten up ok the first time I installed it. The assembly appeared to be bottomed out against the surface they are supposed to seal. But it still leaked. My grip with the o'ring the way it sits is that there should have been more material added to the outside surface of this boss to allow a machined groove to be put on the surface that captured a o'ring that mates with the switch surface and seals with compression between the two. Similar to what Toyota has been doing for over 20 years on some of there vehicles. Not having to blindly push the switch through an o'ring which appears to be slightly larger than the counterbore that it is meant to reside in.
The lip seal which I purchased from Bob's does press fit in to a recess on the front face of the new switch but obviously is not the full diameter of the counter bore in the transmission boss which is normal lip seal practice.
I do not have the old switch to look at the face of it to see if it contained the small lip seal in question.

[AntonLargiader]

...Not having to blindly push the switch through an o'ring which appears to be slightly larger than the counterbore that it is meant to reside in.
The lip seal which I purchased from Bob's does press fit in to a recess on the front face of the new switch but obviously is not the full diameter of the counter bore in the transmission boss which is normal lip seal practice....
You're complicating this somehow. The seal fits completely into the switch body, and seals the shaft to the switch housing. The O-ring slides over the barrel of the switch body and seats into that slight counterbore in the tranny housing, and seals the switch body to the housing. That's all there is.

The seal shouldn't protrude out of the switch, and it doesn't try to seal against any part of the tranny itself.

[klockea]

Anton,
This is my first BMW, and the first time I have ever taken it apart this far. I did not realize there was a seal as part of the switch when I took the original out. Chicago BMW, who I ordered the original parts order from did not mention to me that there was a seal that was also required with the switch.
I did get the switch assembly back in place late yesterday and am going to check it for function before I even put the swingarm back on this morning.
My gripe with the design of this is that there is a much better way to make the o'ring do it's sealing job which would also make it much easier to put everything back together. There is plenty of room to have made the casting boss somewhat larger and machined the face of it to allow the o'ring to be a compression seal instead of having to somewhat blindly have to force the switch body through the o'ring.
Hopefully BMW has made some type of a correction to that situation on newer models. Thanks for taking the time to answer my post.

[AntonLargiader]

...instead of having to somewhat blindly have to force the switch body through the o'ring.
You're welcome, but I gotta come back to this point. Installing it this way is purely your own deal. I can see how this would make it difficult, but I can't see why anyone would want to do it that way.

I probably just have a different perspective on this. I install these things all the time. Pry the old seal out, push the new one in, slip the O-ring on and bolt it onto the tranny. Never had any issue with it.

[alien_hitchhiker]

there is a much better way to make the o'ring do it's sealing job

It is the task of the engineer to better the design.
It is the task of the owner/wrench simply to understand it.

[klockea]

Yes,
It is up to the engineer to better the design. I've been designing/re-designing things for the last 22 years to make a living. Because of that I may pay a little more attention when looking at why somethings do or don't go back together easily regardless if one is very familiar with it or not. As I said, this was the first time I ever pulled one of these apart. Had I known there was a seal pressed in to the face of the switch I would have ordered one the first time.
And I did reinstall it the way it was meant to be installed. I'm simply saying the design could have been simplfied should it need to be repaired by someone not familiar with it. Slightly more expensive to produce, but less likely to be screwed up by someone like myself the first time it was encountered like many of us that have to do our own repairs.
Again thanks for everyones time.