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Any ideas?

McFly

CB750 Member
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Winnipeg
I have a 79 CB750F Supersport. I bought it off a guy who said that it stopped running after he went to start it in the spring...
I have pulled the battery box and battery out. When I connect 12V source I get almost all lights, horn etc and everything working. I have checked the rotor assembly of the stator and the copper disc's are good still as are the brushes. I have new spark plugs just installed, and I have rotated the engine with the rotor stator nut. I have lubricated the piston tops through sparkplug holes. I have removed the valve/cam covers and lubricated everything and also inspected cam chains and toothed wheels. The chains look good as do the teeth and everything is moving. It feels like I am getting compression as I bar it over. I havent checked the individual compression on the cylinders yet... The Phillips screws on the points cover were seized. I tried drilling and then using a screw remover, but the screw remover snapped. I then used a diamond tipped Dremel sphere bit to remove the Phillips pan head in an attempted to free the cover I removed the plate behind the points cover 7 or 8- 1"x8mm socket bolts and will have to reverse drill and re-tapp the points cover (arrg!). The wires are connected but will have to remove somehow since I can't get the exterior cover off.... The starter works outside the engine. When I install the starter and attempt to crank-NOTHING. It isn't blowing the starter fuse though, and I can hear the starter solenoid picking up. The starter teeth look a little worn, but not bad. Is it possible to hold the starter gear train assembly in place while test bumping starter with the points interior cover off? To see what us happening? Additionally, but also concerning, I drained the oil and I could see very fine brass flakes in the oil. It looked like glitter in the oil...Can someone give me some direction to what might be happening? I heard cam chains can rub on piston liners, but cam chains looks good. I also heard that, some bearing can fail in the bottom end somewhere
Please help.
 
'Is it possible to hold the starter gear train assembly in place while test bumping starter with the points interior cover off?'

NO!! BEST WAY TO BREAK THE CASE THERE IS AND ALMOST INSTANTLY even if working right.

Your starter power source is not enough.

You could have simply picked a slightly bigger drill bit than the ignition cover bolts (no points in it at all) to drill head of screw off to then have cover come right off.

All maybe for nothing if you have bearing remains (glitter) in the oil.
 
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