R100R 1993

[Bamboo812]

Thanks for your historical assessment. Duane. Apparently, "legendary motorcycles", like most legends, are based on both fact and friction. (sic)

There, I fixed that for you... (hope I didn't myth anything)

[daz]

Of course, Souljer's situation begs several questions that he's probably asking himself, and that most of the initiated have asked themselves, but that I've forgotten the answers to, if I ever heard them:

1. Why do dry clutch airhead transmission input shafts periodically require this tedious/expensive lubrication service when other vehicles with manual transmissions and dry clutches (like my middle-aged Dodge Dakota pick-up with 200K on it, or Souljer's TR-6) do not?

Because it is a very poor design. All BMWs before the /5 series didn't require a spline lube. We never heard of such a thing and never saw a negative result suggesting that it be done.

2. I think that I know that brick-type K-bikes require the same service (I've never owned one, but some of the sales listings mention "recent spline lube" as an apparent sales point), but do all dry-clutch BMW bikes require this? Should Souljer be kicking himself harder for not buying an oilhead or hexhead?

I can't answer what anyone should buy. I also know nothing about these later bikes in that I have never even ridden one of them. I have no interest of any kind.

3. Why are the transmission input splines apparently so small/feeble/needy of rust-preventing lubrication? Why not make 'em big enough that a bit of surface corrosion wouldn't risk a ride-stopping and tranny-rebuilding buzz/whirr?

Good question and the older bikes have far larger teeth.

Given my ancestry, I may have a privilege of questioning these points of German engineering, where others might hesitate, and, if so, I'm happy to be of public service.

Just look at my name, same source. I do not bow down the BMW god as so many do. We Germans are just people and people make mistakes.

Konrad

Well Konrad you asked. Here is the very specific and involved answer to your questions. This is according to SnoBum.

WHY did BMW use MANY small and not overly deep splines at the transmission input shaft?
Under "Background information"

http://bmwmotorcycletech.info/inputsplinesthrowout.htm

He talks about the size and shape of the spline as well as why they wear.

Really I think most people are aware of this information and the whole operation is so common is does not come up in conversation much. However I'm wondering if those people who live in a dry climate don't see the results of unlubed splines as often as others where the bike gets wet daily. I hope I'm not using up too many electrons rehashing this information.

[Souljer]

Not at all.
I appreciate any information.

As long as you are recycling electrons it's all good.
No need to split any more atoms.

[khittner1]

You're right, Daz---I should've thought of the probable SnoBum treatise before posing my questions.

[Ken in Oklahoma]

You're right, Daz---I should've thought of the probable SnoBum treatise before posing my questions.

Nah! We don't do a lot of "bit-saving" here. Besides, if a person refrains from making a posting because the answer might already be on the internet, well, one of two things can happen: We miss the chance to make a wise-ass comment, or worse we miss the chance to show off our superior airhead acumen. (Or is it the other way around?)


Ken

[bbelk]

As long as you are recycling electrons it's all good.
No need to split any more atoms.

That is too good a quote to not get quoted.
Thanks

[ME 109]

(Or is it the other way around?)Ken

Definitely not Ken. You know that.

[Souljer]

Hi all,

I hope everyone has been doing well.
I've been riding around and enjoying the bike.

A few weeks ago I went to a tech day that was almost an hour drive. I was there all day until sunset, then I drove back.
While there I got the spline lubed and the carbs balanced!! Yay!

I recorded some of it and want to post a video on my YouTube channel when I get it done.

THIS post is for a carburetor problem though.
The bike seemed to be fine. Maybe the idle was a bit low (below 1000 RPM), but seemed fine all this time.
Yesterday I roll the bike out, turn down the fuel taps and the right carb starts pouring fuel; completely leaking!
Today when I had a chance to look, I started with taking off the bowl and trying to wash out the needle valve again.
Not only did that not work, I noticed that manually raising the floats WOULD NOT stop the fuel from draining.

SYMPTOMS:
• Seemed to happen over night.
• Raising floats assembly manually does not stop fuel.

So I'm online looking around online for clues and thought I might stop by here to see what you all might think.
I appreciate any thoughts on the matter.

[Bamboo812]

Sounds like a small piece of crap is preventing the float needle from seating. Did you put new fuel hose on this bike? Old hose can break down and chunks get in the jets, or new hose can shed a piece while being installed. You might get away with removing the float needle and using fuel pressure to wash it out. If not, you'll need to blow up through the float needle seat to clear it. Feed hose to carb removed to do this.

[Ken in Oklahoma]

. . . The bike seemed to be fine. Maybe the idle was a bit low (below 1000 RPM), but seemed fine all this time.
Yesterday I roll the bike out, turn down the fuel taps and the right carb starts pouring fuel; completely leaking!
Today when I had a chance to look, I started with taking off the bowl and trying to wash out the needle valve again.
Not only did that not work, I noticed that manually raising the floats WOULD NOT stop the fuel from draining.

SYMPTOMS:
• Seemed to happen over night.
• Raising floats assembly manually does not stop fuel.

So I'm online looking around online for clues and thought I might stop by here to see what you all might think.
I appreciate any thoughts on the matter.

There can be another problem that looks a bit like a float or needle/seat problem. It happened to me. And I'm somewhat embarrassed about it.

My '77 R100S suddenly started pissing fuel out of the L/H carb. I'm relatively seasoned in dealing with Bings so I went after the problem. I eliminated the usual culprits, trash in the fuel line or seat, a needle that doesn't seal, a burr on the seat, heavy floats, mal adjusted float level and possibly something else that I can't remember now. The upshot is that I couldn't fix the problem. So, In desperation, I posted on Boxerworks for ideas.

Later on I was once again lying on the concrete, looking up at the offending carb, moving the float up and down and unable to figure out how the the gas could still be could be coming out in something like a stream. Then I did something with the fuel line (don't know what theory I was working on then--probably none) when suddenly the flow became worse. WTF! I was witnessing something that was impossible.

It turns out that it was possible. What I had was a cracked rubber fuel line where the fuel line mated with the brass nipple. I thought the thought again, just to make sure-I had a cracked fuel line!

What happened is that the leaking gas wicked around the carb and only looked like it was originating from within the float chamber. And fiddling with the gas line made it worse.

Then, to add insult to injury, when I reported my findings back on Boxerworks Major Softie wrote something that made me cry!

Well, OK, I"m not sure he actually did that. In fact he probably didn't. But I knew in my heart he was thinking it. And it wasn't nice!

Ken