spun rod bearing = metal filings?

[dan filipi]

ok, wrist pin. but what would make the sleeve open up? ......... back to wrist pin, from Dan's pics, which are great, pretty obvious that pin is in there pretty darn good, so again what is it that would make this pin wear enough to knock? ....Crowe

I can't say yet Crowe.
I'm doing a complete rebuild starting with complete reconditioned heads with new springs to rule out the heads first.

Judging by the condition of the piston pin I tore apart and those that are in my engine now which has the knock, I'm starting to think the noise is NOT piston pins but it's early yet.
Once I put these heads on my runner with the knock I'll have the heads and valve train ruled out, at that time I'm diving into the engine.

On your's, if you have one lazy cylinder caused by weak ignition or carb problems you'll here a knock and it can sound very bad!
Have you synced yet?

 

[slabghost]

Listen close to the fuel pump. The tap you hear may be coming from the cam hitting the fuel pump actuator rod. You could try running 20-50 wt oil. Who rides when it's below freezing anyway? Beside me and a few others who happen to be a bit crazy. :mrgreen:

 

[joedrum]

chas the marks are from dan taking it apart with a hammer wrench :builder:

 

[crowesnest3]

Dan suggested maybe"lazy" cylinder, wish I could go there only because it would be new to the hunt, but, carbs have been syncd, valves adjusted, new timing belts, new plugs, compression runs from 173 - 178, new fuel filter, stator nut checked, bought a mechanics stethoscope so I can rule out the fuel pump, "knock" seems located to the rear of block, nearby to stator block connection, or center rear of block. Have gone to a heavier oil Rottela 15/40 that I mixed in a quart of Lucas oil stabilizer .... the 4 quarts I drained out looking for metal filings ( only 750 miles ) - no metal - and one quart Lucas, stirred and poured, leaves one quart of mix for the shelf. The "knock' which is still there has quieted down, almost gone in 5th running 45 - 65, which is nice! Nice especially since I put the stock pipes back on, the Jardines were upsetting the peace of the rural countryside.....anybody interested in a set of Jardines? Oh! also tried yesterday to isolate bad bearing/wrist pin by pulling power to one plug at a time, no such luck, didn't make a difference. Read somewhere that a possible might be the camshaft having some back n forth play, front to rear, so thinking maybe pull the radiator/timing covers to check that and while I'm there double check timing belts, wheels n tensioners, although scoping the timing cover only get the hum/rolling of the wheels n belts, no knock. Really have to say guys the banter back n forth is really turning in to one of the better parts of my day, thanks for the company. :Egyptian:

 

[joedrum]

wrist pins are splash lubed ...and on wings with carbs leaking into the crankcase they dont get lubed very good at all ...being that your noiseis right there by the stator its very possible that the noise is omingfrom those parts ...lots of stuff there ...your stator can actualy be coming apart frm excessive heat epoxy can only take so much heat ....have you looked at the stator connetor for melting ..rectifier connector too.. :mrgreen:

 

[dan filipi]

Given the history we have here from quite a few of us trying to locate this knock I can think of nothing else to do besides checking over everything again.

I'm not ruling out anything just yet.
Hell it could come down to a shifter fork bouncing around!