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Another one of those rebuild stories R50/5

The battery negative case tie down is at the speedo cable boot, so that puts the negative post on the driver's right.

As for the revolutions and setting valves, I don't think about what pistons are doing and which of the four stages of a 4-cycle engine they're in. The object is you want to set the valves for the side that is at TDC on the compression stroke. I usually start on the left side, bike in 4th or 5th gear, valve cover off, standing behind the bike. I grab the rear wheel spokes and begin to turn it in its normal direction, watching the valves. When I see the intake vavle open (ah, intake stroke!), then close, any more turning puts that side on the compression stroke. I stop turning the wheel at the back, sit down on the left side of the bike, and use my hand to bump the rear wheel until the TDC shows up. Ready to set the valves on the left side. You can then just rotate the flywheel 360 degrees to be at the proper position for the right side. But I go through the same process, this time watching the right intake rocker. This assures I haven't missed the TDC mark on the right side.
 
As for the revolutions and setting valves, I don't think about what pistons are doing and which of the four stages of a 4-cycle engine they're in. The object is you want to set the valves for the side that is at TDC on the compression stroke. I usually start on the left side, bike in 4th or 5th gear, valve cover off, standing behind the bike. I grab the rear wheel spokes and begin to turn it in its normal direction, watching the valves. When I see the intake vavle open (ah, intake stroke!), then close, any more turning puts that side on the compression stroke. I stop turning the wheel at the back, sit down on the left side of the bike, and use my hand to bump the rear wheel until the TDC shows up. Ready to set the valves on the left side. You can then just rotate the flywheel 360 degrees to be at the proper position for the right side. But I go through the same process, this time watching the right intake rocker. This assures I haven't missed the TDC mark on the right side.

Thanks you for that useful perspective. It's nice to hear how someone else goes about it. The math teacher in me needs to understand the theorem before using it. So in instances such as these I tend to dive deeper into the how and why much further than what's necessary for completing the actual task at hand.
When spinning the wheel watching the valves open and close, I would do just as you described in watching for the intake to finally close. However, as you said, "I stop turning the wheel at the back, sit down on the left side of the bike, and use my hand to bump the rear wheel until the TDC shows up" I found that when OT came back around it wasn't necessarily on that piston's sweet spot anymore. Maybe I'm just over analyzing the situation and getting myself confused, but once the intake valve closed OT may have taken a while to come back around thus opening and closing everything all over again.

In the end I feel pretty confident that I gapped those rockers sufficiently. And from the on-line literature there's a reasonable amount of room for error with the feeler gauge used to do the measuring. Clymer says intake is .10mm while Duane says .15mm. Anything slightly off (in the smaller size of the gap) may simply result in a little more HP.

BTW, thanks for that battery info.
 
Getting dangerously close to bringing my Mistress out into daylight again. I've developed very poor posture this winter because the ceiling down here in the basement has all these pipes and duct work to hit my head on so I've spent all this time in a hunchback kind of position moving from one side of the bike to the other or getting parts or tools off the selves I've made. This has been a work environment not exactly conducive to the task at hand.
Here's my "what's left" checklist:
1. A little bit of wiring including tying down wires to the frame.
2. Figure out if the rear brake cam was stripped cause none of the bolts I have will fit it (to secure rear brake lever)
3. Adjust Carbs
4. Spark plugs that fit (the ones sent from Hucky's seem too big to push into the spark plug wires.)
5. Install horn
6. Mufflers
7. Battery
8. attach throttle cables
9. Fluids
10. Cross fingers
11. Test crank.

Any advise, thoughts, perspectives are greatly appreciated from here on out please.
 

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I found that when OT came back around it wasn't necessarily on that piston's sweet spot anymore.

When I leave the rear wheel, the intake valve has only begun to close. When it does close, the wheel (and the piston) still travels a bit. My reason for stopping at the rear wheel is to not overshoot the OT mark in my zeal. I want to be sure I catch the very next OT.

I trust you're sure that the flywheel was put on correctly. When at OT, compression or not, the piston should be all the way out. Easy to verify with a chopstick or something non-damaging in the plug hole while the engine is turned.

And from the on-line literature there's a reasonable amount of room for error with the feeler gauge used to do the measuring. Clymer says intake is .10mm while Duane says .15mm. Anything slightly off (in the smaller size of the gap) may simply result in a little more HP.

BMW was all over the map on this too. It was 0.004/0.006 thousands intake/exhaust when I first starting on my /7. The it was 0.004/0.008, finally somewhere along the line it ended up being 0.006/0.008 thousands. It's an Airhead, you're not going to get much more HP out of it!! But having the valves sit on the seats even for a fraction of a second more will help with heat transfer. A slight bit more noise, but it's better for the valves. My 0.02...
 
4. Spark plugs that fit (the ones sent from Hucky's seem too big to push into the spark plug wires.)

Looks like you bought the period correct BERU 5KΩ cap metal-sheathed spark plug wire/terminal sets. Remember, you do need to remove (and discard) the spark plug screw-on cap.

I bought the same parts, from the same place a little over a year ago, water migrated into the electrode cavity, corroded itself in oblivion, and they have now been replaced with NGK resistor caps (p/n: LB05EP)

Here's why > http://forums.bmwmoa.org/showthread.php?t=55485

The NGKs are super-waterproof - the NGK logo ... disappeared with a little black paint :whistle

f_1327712.jpg
 
4. Spark plugs that fit (the ones sent from Hucky's seem too big to push into the spark plug wires.)
.

unscrew the aluminum end cap from the spark plugs. The wires should fit over the bare threaded ends of the spark plugs.

I applaud the work you have undertaken and the job you are doing.
 
My reason for stopping at the rear wheel is to not overshoot the OT mark in my zeal.

It's a PITA, but I always remove the front cover and use an allen wrench in the end of the crank when I do valves ... no over shoot at all, ever. And the wrench makes a great indicator of where you are in the cycle.
 
It's a PITA, but I always remove the front cover and use an allen wrench in the end of the crank when I do valves ... no over shoot at all, ever. And the wrench makes a great indicator of where you are in the cycle.

Lew -

I first used to do that, but turning the engine against the compression was a bit tough, especially in that one particular part of the stroke where you have the least mechanical advantage...possibility exists that the alternator allen wrench can strip. I know people say that the plugs need to be removed, but I dislike removing plugs when it's not necessary. So, I reverted to the rear wheel while in gear approach.
 
That's a valid point Kurt, especially considering that my plugs were a little reluctant to spin out freely after using anti-seize on them for the first time.

I still find it less frustrating than the other way, I like having the visual reference of the wrench as the crank is turned ... and it gives me a chance to check plug condition.

Didn't intend to jack your topic Barrett.... you're kickin' butt on this old machine.
 
It's a PITA, but I always remove the front cover and use an allen wrench in the end of the crank when I do valves ... no over shoot at all, ever. And the wrench makes a great indicator of where you are in the cycle.

Good call!Definitely keep that in mind for future use. Funny thing is, the front cover was off through the whole process. :laugh
 
Thanks for the spark plug info guys!

I spent a small amount of time this afternoon taking the old plug wire and new plug to the local auto part store to see if they could produce something to compare it with. I may be going out on a limb saying this but the good old Vermont boys that work at the local part store always have something in the way of useful advise or information compared to most of the monkeys that work in the major box auto parts stores (Pep Boys, Advanced...blah blah).
They may be rough around the edges and hard to understand but he knew (from experience with a buddies bike) that you have to take the caps off the spark plugs with these "old school" engines.
Again, one of those little details I failed to recognize back in December.

I have a guilty pleasure to share:
I really like the bike's look without the mufflers on. Not only is this not the best thing for the air but I'm sure it will make some great obnoxious racket and make it near impossible to listen to the engine for red flag upon cranking it. I need someone to talk me out of leaving those mufflers off.
 
Fluids. 250ml in the final drive. That Appalachian Engineering can in handy once again as you can see the use of a PBR can as a funnel.

Bad news? After adding lubricants I turned the rear wheel (while in gear) as quickly as I could and heard an awful highish pitched noise. I stand to reckon it's a pushrod rubbin' up against a gasket. It sounds like it's coming from the right side. I'm going to have that side confirmed as the source of the noise by another set of ears tomorrow. It'll have to wait till tomorrow cause if I don't go to bed now my 18 month old won't let me get ANY sleep tonight. Not looking forward to taking the valve cover back off.

If it ain't worth doin' twice it ain't worth doin'. :banghead
 

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Fun Thread

You're doing great work, here.

Two things:

(1) NGK Plug Caps -- It's easy to remove the "NGK" white logo and "logo-perch" with a file or Dremel, then use elbow grease and progressively finer sandpaper to bring back a "natural" plastic sheen to this area of the cap -- makes it generic, and I think it looks better vs. NGK white lettering. Of course, PAINT also works, but -- SOME of us (ahem) are anal as hell about this stuff. Sanding it down only takes a few minutes.

(2) (Old fart comment) I know of no other factor that raises the ire of the public more than LOUD PIPES. I live in "Harley-ville" and most of them seem to run straight pipes, which can, literally, be heard from miles away. Good for performance, IF you're looking for top-end speed alone (Bonneville Salt Flats, anyone?), otherwise, a negative in the mid-range where most of us spend our time.

Far be it from me to tell anyone else what to do, but we constitute a very tiny percentage of the population, and LOTS of people think we're lunatics for riding our machines. ("organ donors") When loud pipes are added to the equation, public tolerance for our "dangerous" pastime goes in the toilet, and we ALL pay for that. No kidding, loud pipes REALLY, REALLY piss people off.

Walking Eagle
 
You're doing great work, here.

When loud pipes are added to the equation, public tolerance for our "dangerous" pastime goes in the toilet, and we ALL pay for that. No kidding, loud pipes REALLY, REALLY piss people off.

Walking Eagle

Thanks.
I needed that.
I agree, just needed to be reminded.
IMO loud pipes are pretentious as hell.

Now about that noise on the right side.....
I took the right valve cover off this morning and rechecked the pushrod's position relative to the tubes and they seem completely clear. The noise definitely exists because Gretchen heard it this morning too. It makes the noise at the same point in the right piston's cycle.
Is it possible that it's just an unlubricated ring rubbing against the cylinder wall? Or is it just some unlubricated something that will stop making noise once the bike is cranked and oil has a chance to circulate?

I'm a little obsessed with this right now cause I was hoping to get her out in the sunshine today and see if she'll crank, blow up, melt, or just sit there looking pretty.
Any suggestions, if you have any thought or experience on the matter, would help.
 
You might try to get a mechanics stethoscope to help isolate exactly where the noise is coming from. It would be nice to decide on exactly what the situation is before starting it.

BTW...what is your plan for breaking it in? Something of a discussion point, I suppose. Me, I'd probably not attempt to start it until I was really, really ready and once started, take it out for a 15-20 minute ride. Starting, stopping, starting, etc., might not be the best approach in my mind...
 
BTW...what is your plan for breaking it in? Something of a discussion point, I suppose. Me, I'd probably not attempt to start it until I was really, really ready and once started, take it out for a 15-20 minute ride. Starting, stopping, starting, etc., might not be the best approach in my mind...

Glad you mentioned that.
Starting it today is not going to happen. Neither is tomorrow. You're right about waiting until I'm really really ready. Like the way loosing my virginity should have been. Wait. Wrong thread, sorry.

I'd like to open that question up to the masses.

I was thinking of trying to turn it over the first time without gas in order to let the oil circulate without flooding the engine. Then open up the petcocks and see if it will start. If so, then work on adjusting the carbs to tune the idle. Then, turn it off to adjust the clutch to pull away and take it down the road for 5 minutes out and 5 minutes back.

I'd like to hear what others have read or have experience in this matter.

I really think the noise I'm obsessing about will dissipate once the innards are well lubricated. I sounds like the noise is coming from inside the right cylinder. I'm guessing one of the rings didn't get a proper coating of oil before putting the piston back in the jug.

So, how would you crank this engine/break this bike in?
 
Knowing you get oil circulation is definitely something to consider. You could probably drop the float bowls and crank the engine for 30-60 seconds to see that oil is making it out to the valves...leave the covers off to see.

There have been threads on engine break-in. My limited experience and reading from other knowledgeable people is that the first 60 seconds of engine running is the most critical. The object of break-in is to get the rings to form in a way that creates the best possible seal. If the rings don't shape themselves a good bit in that 60 seconds, the chances of a succesful break-in go down. The issue is that the most amount of abrasiveness you're going to get is in that 60 seconds. Once the engine is running and heating up, the oil begins to glaze on the cylinder walls and the shaping process begins to slow down. I've heard to start the bike, hold 3K RPMs for 45-60 seconds, drop back to idle and go ride. Also vary the RPMs and gears because the increasing and decreasing speeds create pressure to force the rings more onto the cylinder walls. After that first 20 minute ride, change the oil, let it cool and check the valves. Maybe change the oil at least one more time at or before 500 miles. Might be good after that.
 
I hooked up the battery and popped the 'key' in to see what kind of juice is flowing........nothing. No lights......nothing. Going to look into it when I get a chance.
:scratch
 
Ouch!

. . .I hate it when that happens, but it feels SO good when you find that one little loose wire or corroded terminal. . .

deOxit is a great product, if a little pricey. Also, Radio Shack has some "plastic-friendly" contact cleaner(s) that also do a good job.

A lot of us know this exact pain. Good luck and don't get your dauber down.

Walking Eagle
 
Still looking into that no power thing.....in the mean time, what's up with the swing arm hitting the frame like this? Is this normal? The bike is on the side stand in this picture so don't assume the rear wheel is 'hanging' like when it's up on the center stand.
Does my own weight lend to more clearance here? It's made me angry cause it's chipped away a little paint on that spot. :mad
 

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