New rebuild in the Northwest

[Rob Valdez 79 R65]

Bummer.

When you get the bike up & running, be sure to check your valve clearances every 1000 miles or so for the first year, to check for deficiencies in the metallurgy.  You may want to get a valve-job done before you start putting serious miles on it, if the exhaust valves show signs of closing up rapidly.

Does it have electronic ignition?  A single coil, rather than two individual ones?  Give us a shot of the arrangement of the electricals under the tank, from the right-hand side.  Since this appears to be a 2nd gen engine in a 1st gen frame, there must have been some creative re-assembly done.  That was another significant change between the two.

[Barry]

Looks like I'm without.

Take a read of this http://bmwmotorcycletech.info/IDnumbrs.htm Snowbum explains that the engine number was moved away from the dip stick area around 83 - 84 and also that it was not necessarily any longer the same as the frame number.

This would seem to date your engine much later than the frame.

[Rob Valdez 79 R65]

Yes - I hadn't thought of that.  I knew they stopped stamping the number there at some point, but I didn't remember when.  It could be from a mono-shock R65, or perhaps not even a R65 engine!  That could be (sort of) easily verified by measuring the width of the engine, or at least one side.  
The R65 is a shorter stroke than the Type 247s, making the engine narrower overall.

Measuring one side of my 650 engine is 10 1/4" from the crankcase to the outside of the valve cover.

[bbell1]

One more of many questions to follow:

I'd like to repaint the electrical housing (my name). If possible, I'd prefer doing it as a separate piece away from the engine. I wanted to ask what I'm getting myself into if I pull that unit off - lots of connections? timing belt stuff? Anything? Or does it slide on and off and easily, correctly, reinstalled?

[Rob Valdez 79 R65]

It comes off w/o too much fuss, plus the fantastic advantage of being able to examine the timing chain/gears and tensioner for wear!

Just be warned that it will expose openings into the crankcase into which bits can fall.  Then you have to drop the oil pan to retrieve them.

[bbell1]

Here's some shots from the dismantling that might help.

[bbell1]

Thanks Rob, I did find a lightly etched number on the transmission box, top right side as your article suggested. It reads Z 103641. A digit short and no obvious relevance. Will do as you suggested and take the plunge with the housing. Carefully...

[Rob Valdez 79 R65]

Don't be surprised when you go to remove some of those socket-hex fasteners - a couple of them are "female" caps instead of "male" screws.  It really caught me off-guard the first time.

Do you have a set of hex bit sockets?  These are some of my oldest & most-loved tools:
http://www.sears.com/shc/s/p_10153_12605_00934448000P?keyword=hex+head+socket+wrench&filter=storeOrigin|Sears&mv=tr

[bbell1]

I'm not sure how much has to be unhooked. In trying to pull off the silver cap/stator it seems to be hooked to something in the vicinity of the D- symbol. That electrical connection, white with 3 wires, doesn't look like it would disconnect without undoing the solder anyway.

Also... I'm assuming the ignition sensor (can at bottom) can stay on and won't interfere? Diode board?

[Barry]

All the electrical connects just pull off though they may be tight.

The alternator has to come off next . Stator is easy enough but you need a special hardened screw or pin to remove the rotor. Lots about this on the net. I like this one By Joe Cuda for the illustrations which help explain what is happening when you remove the rotor Allen screw which comes out in 2 stages - first it releases from the threads in the crank and then from the threads in the rotor.http://www.airheads.org/content/view/194/98/

Removing the diode board might be a good idea too as there is a crankshaft bearing in the cover and you may need to use some heat to get the cover off. The ignition bean can could come off for the same reason.  Just 2 Allen screws anyway.

[bbell1]

Thanks Barry. From what I read it seems the stator coils and housing get pulled straight off together. All the electrical connections did come off. i was just worried about the one circled below because that's where the cover seems to be reluctant to move vertical.

Should the coil slide up easily or might it need a little persuasion. I'm just reluctant to pull off the cover and damage the coil in anyway. That would be quite a bit more work then just painting the cover exterior which is all I'm shooting for.

[Rob Valdez 79 R65]

I would try tapping the stator case with a small rubber hammer.

To do the job properly, you really need to remove everything from the timing cover.

Again, this would allow you an excellent opportunity to examine the timing parts.  Not a bad thing to do for a bike with an unknown history.

It would make painting the timing cover much easier, and give you more satisfactory results.

I would buy a tool to remove the rotor.  They are not expensive, and will save you A LOT of grief, as opposed to buying a hardened fastener and cutting it up.  If it breaks in there in the removal process, you have a real mess on your hands.
Properly done, it is no big deal.  But the rotor does pop-off rather unexpectedly, so be ready!

[bbell1]

In for a penny....

The cover is still connected underneath, right at the edge where the D- is printed in the cover. Lifts up easily on the opposite side but a definite connection right where the wire comes down from the 3 tabbed, soldered connection as circled in the picture above. Are these usually un-soldered to continue?

[Rob Valdez 79 R65]

No, the coil stays inside the cover when it is removed, so the wires can stay in place.

[bbell1]

Saved me. Finally deciphered the parts, where to pry, where tap and I have it off. My thanks for both your persistence. Have to learn this new language!

I appreciate the insights.