► In this situation, I would borrow a pressure washer and inject hot water and a very strong detergent (not a solvent !) into the timing hole while rotating the engine to several different positions. I haven't decided the best way to rotate the engine... probably bumping the electric starter. I don't think running the engine is a good idea.

You got to get all the oil out of there and hope it didn't saturate your clutch. The downside to strong detergents may be that you have to grease your clutch spines earlier than planned.

► Time for some good news... You don't have to be exactly at TDC to adjust your valves. One glance at a camshaft will prove that the cam followers are on the base circle of the cam lobe for at least 20º before and after TDC. If you'll pull the spark plugs, put the gearbox in high gear, and bump the rear wheel, then you'll be able to rotate the crankshaft both directions very slowly. A screwdriver inserted through the plug hole while doing this will get you close enough... which is all you need.

Hope this helps.

Thanks Again Wobbly. Seriously.

You have to help me out here. I don't know what the camshaft is, or where it is. I'm a newbie. I have heard the term several times of course. When you say the plug hole? Do you mean the timing hole?

Any suggestions for a detergent to use in the timing hole?

At the risk of stepping on Wobbly's toes, The camshaft is the interior motor part that creates the lifting effect of the push rods, rockers arms and valves. It is located just below the crank inside the motor and is driven by a chain and sprocket combination set at 1 turn of the camshaft for every 2 turns of the crank. Plug hole would be the bore in the cylinder head where the spark plug is fitted. If you remove both spark plugs, you defeat the compression stroke of each cylinder and the motor will require much less effort to turn over manually. Some put the bike in high gear and rotate the rear wheel to turn the motor over manually. My R75/5 has a kick starter which makes turning the motor over manually much easier. To determine Top Dead Center (TDC) watch the valve rocker action. On the exhaust stroke for either cylinder, the valve rocker nearest the exhaust header will rise on the pushrod and open the exhaust valve. When that rocker closes, the intake rocker, the one closer to the carburetor, will open in a similar fashion. This is the intake stroke. When that valve closes, you are on the compression stroke. This is when you want to go slowly and watch for the piston to come in to view in the spark plug hole when the motor approaches TDC. Also, this is when you will see the timing marks on the flywheel thru the timing window (hole) on the side of the motor, assuming the flywheel is correctly installed on the end of the crank. On my R75/5 the order in which they appear is "F" for full advance, "S" for spark or static timing , and "OT" for Top Dead Center. The motor turns clock-wise when viewed from the front. Your 1993 probably doesn't have these same characters for markings, but there should be markings.

At the risk of stepping on Wobbly's toes....

Perish the thought ! This is a team effort to help a fellow Airhead owner. This is absolutely not the "Wobbly Show"; never was, never will be ! I seriously appreciate the help.

JHA -
• The place for you to start is to learn the "4 strokes of a 4-stroke engine". Here's some good YouTube videos...
https://www.youtube.com/watch?v=fNcZDrfT498
https://www.youtube.com/watch?v=cB1k7GLgv2s

• From that you learn the full engine cycle takes 4 piston strokes, or 720º of crankshaft rotation (2 full turns).

• Thus we understand that each piston reaches TDC twice in each full engine cycle.

• To smooth things out, our Airheads have 2 cylinders which are firing 360º apart. So when one cylinder is on stroke #1, the opposite cylinder is on stroke #3, and so on. When one cylinder is at TDC after the compression stroke (with both valves closed), the other cylinder is at TDC at the end of the exhaust stroke (with both valves open).

• Valve clearances are adjusted near TDC when the valves are closed and the rocker arms are loose and have slack.

• Thus, with both valve covers removed and a screw driver down a sparkplug hole to detect piston travel.... when you find TDC on one cylinder then you've found TDC on both cylinders. But only one set of valves can be adjusted, because the other cylinder is 360º away from being in the correct position. In fact, at TDC the rocker arms on one cylinder will be tight and busy holding both valves open, and the rocker arms on the other cylinder will both be loose and in position to adjust the clearance.

All the pieces of the engine either support the movement of the piston, the movement of the valves, or the general lubrication of both systems. When you break it down into its function, it's much easier to understand.

Hope this gets you started.