Home stretch on the 750

Hey all... well after taking a month or so off, I finally got back to the Commando restoration. First thing... for some reason I haven't been able to sign in with my old screen name Robb2013. Tried everything, finally reregistered under this name. I kind of lost steam in this project after all the bs I was having with the rear wheel being off center etc. I eventually realized that the Harley shop put the offset on the wrong side of the wheel. Had to bring the whole bike back to his shop so he could confirm that he in fact had fucked up. I credit the guy though because in spite of a lot of bitching, he ultimately made it right. That was kind of the last straw with my patience on this project however, so I then had to walk away for a bit. ANYWAY... I'm back at it again, and pretty close to putting oil in and firing this thing up.... just need to figure out a few things with the wiring harness. For one, I have a few loose unmated wires that I'm wondering if I missed or if they just don't apply to this bike. I'm charging my camera batteries right now and will post a couple pics a little later this evening. I've also ot a couple questions as far as the headlight wiring goes... when I turn on the headlamp I have to flip the on off switch from right to left. Is this correct? I tried turning the switch around but the hole is flat on one end and won't go in the other way around. I've never seen a switch before that operated in this direction. And then, when I have the head lamp on and flip the flat vertical switch on the rh controls, the headlamp goes off and the green idiot light on top of the headlamp comes on. (High beam indicator maybe and high bulb burned out?) Is this normal? That's about all for now. I'll post some pics of the mystery wires as soon as my cam's charged. Later.

Oh, one other thing... since this bike sat for about ten years or so, I was thinking about putting some 10 wt. oil in for the start up, letting it get up to temp, then changing the oil with straight 40 wt.... just to get the rest of the leftover gunked up oil out. Any comments or suggestions on this?

There are extra wires.

My switch works the same way.

Oh how I love the pensiveness of impending truth or dare on first run in.
Don't go below 30 wt no matter what, best in my opinion and more that sufficient I've found is Rottela hi detergent diesel grade 15/40. There is almost a shoe box worth of usless loops and dead ends for police gizmos. Takes close look at wire graphic to trace em and tape off to ignore or remove, ugh. My head lamp shell switch connects with a flip form upright center to laid to RH. Has a flat that dictates mounting position. Green indicator is hi beam and should come on with hi beam by bar paddle depression or flasher button tagging. Once started keep over 2000-2500 rpm and blips above to bed in cam/lifters and seating rings if needed. After just a few times of this to diddle hot idle stable, I'd dump the first oil and use some non synthetic next few 100 miles to next change use long term oil choice. Don't forget only takes one over tight primary event to trash tranny and clutch stablity. Re-torque wheather needs it or not each cool down you can over next 1000 miles or so, then maybe every 5000, unless leaks show up, then likely too late anyway.

Bike requires oil with high zinc content due to flat cam followers.
Old oil had zinc but modern standard oil has little or none.
Once bike has seated rings I moved to Synthetic.
Mobil 1 V-Twin 20-50 which has the zinc you need.
Others out there.
Look for threads on this site as lots of discussion on oil.

hobot said:

Oh how I love the pensiveness of impending truth or dare on first run in.
Don't go below 30 wt no matter what, best in my opinion and more that sufficient I've found is Rottela hi detergent diesel grade 15/40. There is almost a shoe box worth of usless loops and dead ends for police gizmos. Takes close look at wire graphic to trace em and tape off to ignore or remove, ugh. My head lamp shell switch connects with a flip form upright center to laid to RH. Has a flat that dictates mounting position. Green indicator is hi beam and should come on with hi beam by bar paddle depression or flasher button tagging. Once started keep over 2000-2500 rpm and blips above to bed in cam/lifters and seating rings if needed. After just a few times of this to diddle hot idle stable, I'd dump the first oil and use some non synthetic next few 100 miles to next change use long term oil choice. Don't forget only takes one over tight primary event to trash tranny and clutch stablity. Re-torque wheather needs it or not each cool down you can over next 1000 miles or so, then maybe every 5000, unless leaks show up, then likely too late anyway.

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Has anyone ever compiled a checklist for a first start up after restoration? My pensiveness stems from paranoia, fueled mostly by past impulsive bone headed mistakes.

LOL! the list is endless and not way to really know but truth and dare leap of faith...
You can expect to hear the whole engine grinding up stuff and chipping off parts to ring and rattle and whirl and smoke and spit till heart settles its just normal ancient dinosaur behavior.

Fill oil spaces as much as can in crank and rocker area but don't turn engine over to pump oil as grinds off all the pre-lube to unprotected ZAPP metal. Just start the bugger and rev over 2000-2500 and watch for oil and foam to show in tank after most a min of lip biting, then stay on it blipping till rather hot for 5 min or so. No need of cooling fans as its not burning much fuel heat to spin w/o load I've found monitoring oil and head and exht. temps. Rings should be mostly sealed by then and cam bedded in enough can shut down and clean up and diddle faults or be in an extra pensive state of not finding any... yet. I'd do this a few times then change oil to hit the road on. If oil filter its educational to open it now and put on new one for next year or two through many oil changes as not much to filter after break in, er a - I mean run in.

Diddle base spark timing up till hints of back fire then retard to just don't and only then bother to mark and measure where it lands objectively. Check valve lash and chain tensions and rear brake adjustment and tire PSI, usually about 2 lb less in front for most neutral steering. Don't lug her but don't stay in low gears long as accelerates tranny wear and clutch wobbles.
Check plugs for mixture after a while. Carry test light and wire repair kit and bailing wire and hose clamps and zip ties and tape for first 1000 miles and likely there after too. Let someone know your routes and don't leave off forgeting to put fuel in tank like I did on my first ever restoration to have in die in middle of night a ways from open station. I lucked out only 1/2 mile from a truck stop and only one 1/4 mile up hill push to coast rest the way down. Re torque till blue in the face everything that gets warm when run. Then get back to us with the new name that floats to mind.

hobot said:

LOL! the list is endless and not way to really know but truth and dare leap of faith...
You can expect to hear the whole engine grinding up stuff and chipping off parts to ring and rattle and whirl and smoke and spit till heart settles its just normal ancient dinosaur behavior.

... fuel in tank like I did on my first ever restoration to have in die in middle of night a ways from open station. I lucked out only 1/2 mile from a truck stop and only one 1/4 mile up hill push to coast rest the way down. Re torque till blue in the face everything that gets warm when run. Then get back to us with the new name that floats to mind.

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Well... this hasn't exactly been a ground up restoration. Redid most everything but the motor. It had 16K on it and was supposedly running fine last time it was shut down 10 or 15 years ago. It's got compression up the yin yang so hopefully it will start with minimum loss of hair... so I really don't have to consider break in... just more of a wake up from a deep sleep. What do you suggest under these circumstances Bot... same as you described in previous post?

Oh ugh, un-attended decades old engine may need more re-break in run in than a new one so I'd still do the basic 1st start up and stay rev'd up till fully warmed up then re-torque and oil change before hitting road fate finish up. Expect more electrical grimlins than mechanical but maybe oil leak counts.

Yeah, I'm finding that to be true. Yesterday I pulled both plugs and checked them for spark by grounding them to the head . Right plug had spark but when I checked the left one it blew the fuse. WTF?

HA! Just as I suspected, a mystery machine has a hold on you and glad to hear it ain't me or Wesley this time. Wes told me he spend our LOP day digging into the ancient harness bullets and bends and cluster fooking till he found a loose connection to the light and power to Boyer. Only I can think at moment beyond your/me WTF is maybe LH coil dead shorted? I have had ballast resistor go bad so it smoked paint till a fuse blew.

Rechecked the wiring diagram today, everything's wired properly... also checked the points and regapped them. Still, no spark when I kick it. Could both of these coils be bad?

Both coils bad? not near as likely as both contact breaker condensers by just age of existence. Even be suspicious of new condensers as I've had to dig old out of trash to finally get spark after crazy making exam found nothing wrong but pure desperation attempt. I think ya might be able to test coil by leaving a plug on and touching hot wire to a terminal the other earthed and watch/listen for the snap.
Pretty easy to check in power coming out of ballast and reaching each contact breaker. About any condenser you can mount should work, chain saws to old chevy's or Harley's but may not be best optimal dampening match for least contact arcing as all brands of points are all pretty much same material and plate size which is what determines condenser capacity.

hobot said:

Both coils bad? not near as likely as both contact breaker condensers by just age of existence. Even be suspicious of new condensers as I've had to dig old out of trash to finally get spark after crazy making exam found nothing wrong but pure desperation attempt. I think ya might be able to test coil by leaving a plug on and touching hot wire to a terminal the other earthed and watch/listen for the snap.
Pretty easy to check in power coming out of ballast and reaching each contact breaker. About any condenser you can mount should work, chain saws to old chevy's or Harley's but may not be best optimal dampening match for least contact arcing as all brands of points are all pretty much same material and plate size which is what determines condenser capacity.

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I find power at both coils with key on or off. Is this normal? Also... I've got no spark at the points. Mitch Klemph has Asian knock off coils for 27 bucks. He says he sells more of them than the stock ones and he hasn't had any complaints yet. (54 vs 170, I'm liking them).

Power at coils with key off ain't right. Key on power flows thru key to ballast then to points contacting to charge coil, then open-break to fire coil. Possible someone hooked a red wire up thinking its a power lead instead of earth return. Must trace wire logic to see where its gone wrong. Possible to have bad key switch that don't shut off. Half the time the only way i've gotten spark right was replacing parts like condensors or coils or ballast or spark plugs.

hobot said:

Power at coils with key off ain't right. Key on power flows thru key to ballast then to points contacting to charge coil, then open-break to fire coil. Possible someone hooked a red wire up thinking its a power lead instead of earth return. Must trace wire logic to see where its gone wrong. Possible to have bad key switch that don't shut off. Half the time the only way i've gotten spark right was replacing parts like condensors or coils or ballast or spark plugs.

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OK... how about this then: I disconnected the positive lead from the battery, put the negative probe of the volt meter on the battery and the positive probe on the positive side of the coil and guess what? 12.5 volts.

You are reading the charge in the capacitor.

bwolfie said:

You are reading the charge in the capacitor.

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That's what I thought, but then I disconnected the positive terminal on the battery, put the negative probe of the meter onto the negative terminal of the battery,and touched the positive probe of the meter onto the gear sprocket on my bicycle, which wasn't touching the Norton, and read 11 volts. Would be interesting to see if someone put a meter from their negative battery terminal to the positive terminal on one of their coils and see what it reads with the key off.

You're confusing me, neg or pos ground on the Norton? Can you turn on a 12V light bulb from the neg term on the Norton to the bike not touching the Norton? I'd like to see that. Free electricity?

Dave
69S

DogT said:

You're confusing me, neg or pos ground on the Norton? Can you turn on a 12V light bulb from the neg term on the Norton to the bike not touching the Norton? I'd like to see that. Free electricity?

Dave
69S

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It's a positive ground bike. Wow... I never thought of that. I'm going to hook the battery up to an inverter then to the main bus of my house's electric meter. Com Ed will end up sending me a check each month.

Modern voltmeters with extremely high input impedance can read voltages nearly through the air. You need to be careful how you measure things and think about what is going on. It's better to read the voltage drop across some load so you're not measuring 'air'. I'd measure everything from the positive ground, if you have a good ground on your bike. If your meter is that good, disconnect the battery and read the resistances at various points around the bike from the positive ground battery terminal. Discharge your MC2 before hand by grounding the neg lead (battery disconnected of course) for a minute or so, or disconnect the MC2. Your resistance readings should be below .5 ohms less is better, I think mine is around .2 ohms anywhere I measure. You might have to factor in the lead resistance which can be as much as .2 ohms, even on a good meter.

If you have 12 volts on your coils all the time, they will get hot.

If you measure things from the neg terminal on the battery, it's really hard to tell what's going on because you're starting off at a higher/lower than ground potential. You could probably measure 12V off your fingers from the neg terminal.

Dave
69S