Today, a bit sad and depressed about my airhead

[Lifebeat]

Might sound like a stupid question, but what are the "SPs"?

For the Helicoil, the hole looks nice and straight, no hope of finding remaining threads... Taper thread plug? You are refering to a new plug right? Because the one I have on it now is not tapered.

As for nearby friends, I'm pretty much on my own I think. Not worried so much about the work, it's just that I ask many questions in order to be prepared with parts and tools, so that work is efficient when I get into it.

Thanks for your help everyone!

[Jean]

SP = Spark Plug.
Yeah. Taper thread refers to a pipe-thread plug in a size to fit what is the new hole size. I think this was assuming there were SOME threads left.
NO threads at all might allow an insert to be installed. It is bigger than a helicoil and there might be enough material in the hole for the threads of an insert. It looks like a metal sleeve with threads on the inside AND on the outside. The outside threads are "interference" fit threads, and they are more permanent than a helicoil especially a helicoil that's been installed carelessly which is probably what happened with yours!
Have you got ANY shop manuals at all, aftermarket or otherwise?
If not, you'll have to check the various web sites for instructions and cautions on taking the rear drive and driveshaft (and swing-arm) apart. Duane has some really good info and so does Snowbum. I think there's a link to Duane's site earlier or maybe in another post, and you can find Snowbum's buy just searching on Snowbum+BMW+motorcycles. Additionally, the /5 website has some good info that is applicable to your bike and the IBMWR (Internet BMW Riders) site has an airheads section with lots of informative write-ups.
I've rebuilt my rear drive and installed a rear main seal and some other little stuff...so it's not impossible with help from the forum. Just too bad you cannot go riding just now...oil slinging is a serious problem.

[Norm T R100T R1150RT]

Just a thought - do they make a "freeze plug" small enough for a temporary repair ? I carry a larger one in case the oil level view port blows out on my Oilhead.

[Norm T R100T R1150RT]

Smallest I found with a quick search -
http://www.oreillyauto.com/site/c/detai ... &ppt=C0142

[Duane Ausherman]

Just stick a tapered rubber stopper in and screw it in. You may have to trim it so that it doesn't go in very far, or it will hit the bell coupling.

[melville]

Just stick a tapered rubber stopper in and screw it in. You may have to trim it so that it doesn't go in very far, or it will hit the bell coupling.

That's the difficulty with any drill/tap operation in that area. There's a big round nut which holds the pinion that overlaps the hole our hero wants to work with. Tapping it to any size needs a regular tap, a bottoming tap, and maybe a couple steps in between--perhaps grinding the tip off the regular tap to get the to the larger part of the taper if you don't want to remove that big round nut (I know I don't).

But a rubber plug would work nicely, maybe with a hose clamp going around the whole FD housing for some positive retention.

My own was tapped just a wee bit oversize (1/2" instead of 12mm) by a local shop. The threads are a touch loose and it is weeping the tiniest bit. I may add some sealant to the plug sometime, and wait on the big fix until I get the splines redone 5 or 10 years from now.

[Major Softie]

Just a thought - do they make a "freeze plug" small enough for a temporary repair ? I carry a larger one in case the oil level view port blows out on my Oilhead.

That is SUCH a good idea, especially since the one on my Oilhead has just begun seeping a tiny bit. Do you remember the size? I know, Google is my friend....

[Lifebeat]

Ok, this is all a bunch of very nice info! I'm leaving for the weekend, but when I get back, I'll search this freeze plug (because at the moment I have no clue...)
Thanks a lot guys! And have a good weekend!

[Chuey]

Lifebeat, not mentioned here, so far, is the easy availability of good used parts. The final drive ratio is stamped, very clearly, on the front end of the final drive housing.

As for the heavy feeling in the steering, if you feel that at speed, it may be something. If you feel it at very low speeds, consider the size of the wheels you're used to on scooters and that the larger wheel will naturally have more centrifugal - I'll call it stability. You resisted Jean's suggestion of making contact with other airhead riders but it may help immensely, to either have someone else ride your bike or to ride that of another.

It was mentioned in passing in another post, but I have found the Clymer book on airheads to be most helpful. Used ones go for about $30.00 and new ones are about fifty bucks - the best fifty I spent on my bike.

I'm not smart enough, evidently, to navigate my way around Duane's site but what I have found there was helpful. Snowbum's is easier, as it has a very good index of articles.

These are some very cool machines and I predict that you'll find your way around and you will lose the blues.

Chuey

[Jean]

A freeze plug is a pressed-in thing. I'd go for the rubber plug suggestion so as not to mess with what's left of the housing.
The more you remove metal, the harder it will be to FIX what you've got.

You did not report on how much oil you found in the final drive, or in the driveshaft tube...OR in the transmission. It is everso possible that the driveshaft tube was overfilled and when you removed the plug and found the ruined helicoil it was able to get out. The driveshaft is running real fast. A little oil goes a long way, like blood, when it comes to making a mess. The point here is none of these oil chambers are under pressure, so oil getting out is getting slung through a void...and that is easy to happen if there's too much oil somewhere.

Stuff on Snowbum's site is at the end...Duane's is all over. BUT, the info is invaluable. The IBMWR site is more organized but there's not as much stuff for airheads.