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Discussion Starter #1
I know, pretty technical, but, is there any pressurized oil feed to the primary case?

From looking at it, it doesn't look like there is and that the chain and clutch simply sit in an oil bath and its lubed by the oil that sits in the primary case.

I am new to HD engines, so I just want to make sure what I am seeing is correct.
 

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Discussion Starter #2
Ok, took it apart, looks like its definitely NOT supposed to share oil between the gearbox, primary drive, and the engine.

I have one hell of a leak on my primary drive side, and, next question becomes, how do I get the primary drive bulkhead off so I can weld this thing.
 

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First, you're 100% correct, no pressurized oil in primary or gearbox; they share the same oil, which passes through holes in the trans trap door. Engine oil is dry sump, contained within engine and oil tank, lines (well sort of, not counting the leaks...)

Not sure what you mean by "pirmary bulkhead". The outer primary cover simply unbolts, and it sounds like you have that off already. The "inner primary" is integral with the engine case. You don't get this "off" without complete disassembly of engine and removal of trans innards; it's the left engine case. What's leaking? What needs welding?
 

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Discussion Starter #4
Yep, I was trying to get the trapdoor off..

Any tricks for that?

The crack goes under the trapdoor, all the way to the seam between the two crankcase halves. I have to weld it all to be able to stop the leak.

I just want to get the bike up and running so I can start enjoying it,

I don't want to tear it completely down until I get some bigger pistons, cams, and rods and do all that stuff at that time.

If I can get at it, I can clean it up and probably tig weld the left crankcase and fix this leak from inside. While I am at it, I will probably weld up the drain plugs and I will just use a siphon pump to drain the case from now on. Unfortunately everyone is under the idea that tighter is always better until you crack the case. :(
 

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Oh, is that what happened? Someone overtightened a drain plug? It must have had pipe plugs fitted at one time? The factory plugs are straight, coarse thread and they have sealing washers on them. The trap door is a snug fit on the line-up dowel pins. Remove the drive sprocket (rear chain transmission sprocket) and tap the mainshaft with a soft hammer. Be careful, all the transmission guts are going to come out with the trap door. Do you have a manual for that bike?
 

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Discussion Starter #6
Ya, that started the FIRST crack lol.. Someone just did a pipe tap on it,and put a pipe bung in it..Looks like a 3/8 18tpi. Ugh.. cracked the plug boss...

But, after further inspection, I find evidence of a broken tensioner and a chain that got jammed between the floor of the case and the clutch basket. That is the "other" crack, the one thats actually leaking worse lol..

Yeah, I had a green valley moment and forgot about the chain drive sprocket WTH?!?! I was tired.. Luckily, I never pry anything very much, if it don't go, look at it again, and again, and again.

Sometimes its better to get another pair of eyes or just go get a sandwich and come back to it rather than hammer or pry on anything that is worth more than a years salary lol..

I have a manual, but, after looking at it I probably won't use it much except for torque values and clearances. I read through it, got my "Oh you dummy" and pretty much have the thing memorized now as far as assy. and teardown.

But, ya, a bit of a DUH moment. Sad thing is I work on all sorts of machinery in my day job, everything from avionics to cnc controls to automated equipment. I should know better.
 

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Ah, don't sweat it. I was a Benz technician for almost 20 years. Something different is still something different. I use the book, read through the instructions before starting a job, at least, so I know if there are nay pitfalls to look out for.

I'd be careful about following the book when setting up and shimming the trans prior to reassembly. That's a little bit of a tedious process, mostly done on the bench but some in and out of the case when you get to the last step. Don't forget to check play of the mainshaft in the bearing on the output side of the tranny; there are different size rollers for this bearing to get the play just right.
 
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