tappet adjustment screws

[dummysales]

My 83 Aspencade 1100 had a problem with a leaky front cam shaft seal. I pulled the left side timing pulley and replaced the seal. It ran before I did this. When trying to check the timing again, I've rotated the crank via the back end bolt and it gets to a point where it will not go any farther.
To try to overcome some tappet clearance issue, I pulled all the tappet adjustment screws and lock nuts. In the process I find that all eight tappet adjustment screws have a thread issue about half way down the screw. The lock nuts will thread about half way and get stuck there. Back it off and put it on from the other end and the same thing occurs. All eight do this. Is this a factory norm? Why?

I can tell you with the help of a local machinist we've identified the threads as nominal 6 mm 0.75. (5.9+ mm). I can buy a new set of 8 for $50 at Goldwingparts. Is this a common thing for 1100 engines? I can roughly screw past the hang up by using the nut and a screwdriver but don't wat to stress the old screws. Is it reasonable to save the $50 and tinker the screws?

An additional problem is how to diagnose and fix the fact the crank won't turn past a point where only one tappet without the adjustment screw in place is hard against the cam, which I believe is the sticking point to the rotation of the crank. Ideas?

[dummysales]

BTW, I replaced the timing belts according to the service manual, started the bike, and smiled. Then saw the oil leak mentioned above. This is what has me stumped about the crank not turning past that one tappet location (left side , third from front. All other tappets are loose).

[Track T 2411]

When you changed the seal, did you possibly rotate the cam or crank? It only takes being a couple of teeth off to create a piston/ valve clearance issue, and once a valve gets bent it may not close enough to allow the engine to rotate. Another possibility is that the cam pulley is backwards. The pulley itself can be used on either side, but it has timing marks on both sides of the pulley that are different, depending on which side it's installed on.

[dummysales]

I tried my best to only pull the pulley straight off. I do know they are used on both the left and right side. I believe there is a way to tell that, but don't recall it right off. It is possible I reversed it.

Thank you for indicating the valve issue. That's the type of thing I was leaning toward, but didn't want to pull the head and not be the issue.

Looks like a little wrenching is in store...

Thanks, Track T.

[Track T 2411]

IIRC, the pulley has one side marked 'left' so looking at the bike, one pulley should have that visible, and the other, not. That would be the quickest way to tell.
Concerning the tappet screws, IIRC, I was able to turn the screws all the way out with little resistance, but it's been a few years since I did that work. I do know that I was able to make a full revolution of the crank with all the screws out and no belts installed. This allowed me to set each cam at or near the correct timing mark and get the crankshaft/ #1 piston to TDC timing mark in the timing window.
This procedure will allow you to verify that the belts are installed correctly, readjust the tappet clearance, and at least see where you're at without pulling a head...

[Rambozo]

Did you align the timing marks before you removed the cam pulley?

[dummysales]

At this point I can't be sure but I was following the service manual, so it's likely. Wouldn't have been difficult since I had replaced the timing belts and ran it afterwards. All I had to do is turn the crank to put it back at TDC on the crank.

[Track T 2411]

Can you turn the crank to TDC (forward or backwards)? I think you almost have to verify that the belts and cam pulley are installed correctly, and proceed from there.

[dummysales]

That's where I figured I'd have to start, but wasn't sure trying to turn the crank backwards would work. Probably confusing the issue with the starter sprang thing...
Thanks. Believing taking the timing belts off and starting all over with that process will offer the best route.

On hold for a few days...

Cheers.

[Track T 2411]

We'll be here, lol! Good luck!

Oh, it might be easier (and less likely to loosen) to use the crank pulley bolt to rotate the engine at this point...

[dummysales]

Couldn't stand the suspense, so I took the radiator off and reviewed the timing situation. The crank pulley (Photo 1) is TDC as indicated by the view port for #1 T (Photo 2). Then look at the cam marks relative to the end case mark for perfect timing (photos 3 and 4). Nothing I do changes the way the cam pulleys' marks line up with the case reference triangle.

The crank rolled both counter and clockwise, so I don't believe anything inside is bent, but the belts weren't connected either. I'm not moving the crank pulley again until I find out if the cam pulleys being out of notch alignment by those "one belt tooth off" distances makes a significant difference in a forty year old machine. Any comments anyone?

[dummysales]

BTW, I've checked to see that the #1 cylinder (right side sitting, forward cylinder) is at the top end of stroke. I've played with the tappet adjustment screws and 7 of 8 seem to be able to be used. the 8th is jammed tight. replacement in order.

The other thing about #1 TDC cylinder is the rocker arms are totally loose, but when starting the adjustment screws on the tappets there's not enough screw length to contact the cam lobe. Makes it impossible to set the tappet clearance... Something isn't right...

Never had this issue with my 750 after fifty years of ownership.

[Track T 2411]

BTW, I've checked to see that the #1 cylinder (right side sitting, forward cylinder) is at the top end of stroke. I've played with the tappet adjustment screws and 7 of 8 seem to be able to be used. the 8th is jammed tight. replacement in order.

The other thing about #1 TDC cylinder is the rocker arms are totally loose, but when starting the adjustment screws on the tappets there's not enough screw length to contact the cam lobe. Makes it impossible to set the tappet clearance... Something isn't right...

Never had this issue with my 750 after fifty years of ownership.

There's your 'smoking gun'... a (one or more) valve is bent, and will not close completely, which is why the adjustment screw isn't long enough to make contact. It also prevents the engine from rotating.
A leak down test will most likely confirm this...

[dummysales]

Thank you. Track T.

waj

[dummysales]

Well, the good news is I know what the problem is.

anybody have a favorite used parts dealer? There are a few on ebay, but most are not 83 specific. Will an 82 or 81 version head work?

[Track T 2411]

All the 1100's heads are the same... but, um, isn't that a hole in the piston?!?

[dummysales]

That, too! Two photos

[Rambozo]

Probably more cost effective to get a used engine or even a parts bike.

[dummysales]

For Sale: 1983 1100 Aspencade basket case. Bring a big basket, bike deconstructed to repair busted valve/piston. Cases still together. New wiring where starter circuit wore through near diode. Ran good at that point. Replacement of timing belts done wrong. Missing one side cover. Make offer. My ID photo is the bike.

[Track T 2411]

Sorry for the bad luck... except for your being halfway across the country (and The Boss probably not being too happy about it), I'd jump on this...

[dummysales]

Well, Track T, you never know what a decent offer would do to move us closer!

Happy summer. And thanks for leading me to the issue. Might have to go back to r/c aircraft…

[WingAdmin]

Ouch. That's a mess.

Inexpensive borescopes can be had on Amazon for around $25 and they are now small enough that you can insert them in through a spark plug hole to examine the inside of a cylinder. This will go a long way to diagnosing this kind of problem.

[dummysales]

Thanks, Admin. About done with the whole mess. Up on Marketplace for the right guy with a need. Cheers. waj

[dummysales]

If you're looking for '83 Aspencade parts or the whole thing (engine shot), it's up on Facebook Marketplace. I'm in northern SC.