1986 Aspencade Resurrection

[3KidsinAustin]

I have used a battery operated drill to lap valves. Finger pressure on the valve to keep in place, and low RPM with the drill, works not too bad.

I thought about doing that as well, and would likely go that route if I had more to do. I wish there was a way to clean up the intake seat more, but it looks to me like too much material is gone to get a super smooth finish.

[Fred Camper]

My bet is compression will improve in 2 up near cylinder 4. Fingers crossed.

[3KidsinAustin]

My bet is compression will improve in 2 up near cylinder 4. Fingers crossed.

I am pleased to announce that Fred is WRONG!!! #2 not only beat #4, but exceeded! Bolted the head and valve train on this afternoon, filled the defoaming chamber and bled (again) the hydraulic adjusters, then hooked up the compression gauge.

#2 resulted in a rockstar way, handing in 145 psi. This is up from 75 when I started and as low as 60 with my first failed pass at valve lapping.

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#4 also improved, although not by as big an amount and not as high an end result. Given the condition of its intake valve seat, not surprising. It turned in a 135 psi result, up from 125 initially and dropping to 120 on the first valve attempt.

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Neither of these results are really "great" per the service manual, but I think there could be some room for improvement as it gets some miles under it and loosens up the rings. I have a bit of seafoam rolling around in the oil pan, about 4 ounces that I dumped in after cleaning and bleeding the adjusters the first time. Hopefully that might help, and then I can change the oil after a bit of riding.

Tomorrow I'll hook the cooling system back up and run it up for awhile to sync the carbs. Hopefully no white smoke out the exhaust this time either! Ran it for about 30 seconds and no wild smoke then, but I'm so low on gas in my aux tank that it didn't like it when I rolled on the throttle.

[ericheath]

It looks like you’re using a long tube/hose from cylinder to gauge. I think Cliff had some info on this causing numbers to be lower than spec, but actually might be close to spec? Anyone?

[3KidsinAustin]

It looks like you’re using a long tube/hose from cylinder to gauge. I think Cliff had some info on this causing numbers to be lower than spec, but actually might be close to spec? Anyone?

I think the perspective of the picture might make the hose look longer than it really is. At least the same equipment was used for each of the trials for comparison.

Interesting about the length of hose altering the numbers, though. At least. Is the cylinders are now all close to each other in readings.

[3KidsinAustin]

Bolted the cooling system back onto the bike and filled the system with fluid. No matter how hard I try, I manage to dump coolant down the front of the engine - even using a nice angled filter. Clearly just a glutton for punishment. More on coolant later...

With everything bolted up, I was having no luck getting the bike to start. Couldn't figure what could have gone wrong as I'd done a short run yesterday and it fired up fine. Turns out I was getting no spark to cylinders 3 & 4. Went thru the troubleshooting manual, even swapped signal wires to the coils - which made 3&4 spark but lost on 1&2. OK - coil is good, just not getting a signal from the ICM. Fortunately, this bike came with four or five extra ignition control modules. Put another one on and had good spark on all cylinders. Yeah! Ran it up for a bit but not for long as I think I might have a bad water pump and water coolant leaking into the oil. Will drain tomorrow and see what it looks like.

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After this bike is done, and I'm looking for a different type of project, I might take this apart and see what it looks like on the inside. Wonder if there are any fix-it guides for these modules?

On to coolant - the oil looked a little chocolate-y when I pulled the valve cover and the oil level seemed higher than it should when I checked the dipstick. Plus, I spotted a drip coming from the weep hole under the pump. All signs seem to point towards a failing water pump. Another challenge before getting this old gal back on the road!

[gltriker]

It looks like you’re using a long tube/hose from cylinder to gauge. I think Cliff had some info on this causing numbers to be lower than spec, but actually might be close to spec? Anyone?

I think the perspective of the picture might make the hose look longer than it really is. At least the same equipment was used for each of the trials for comparison.

Interesting about the length of hose altering the numbers, though. At least. Is the cylinders are now all close to each other in readings.

A proper 12mm compression test adaptor will have its check valve positioned as close into the cylinder head's combustion chamber cavity as possible.
Visualize where the spark plug ground strap is positioned in the spark plug hole when the spark plug is fully installed and torqued into place. That's the place the check valve belongs.
If a typical generic 14mm to 12mm reducer adaptor is utilized, the all-important check valve is always positioned farther away from the spark plug hole opening into the cylinder head chamber.
In essence, that extra unchecked area in the spark plug hole and 14mm to 12mm adaptor is added as if the tested volume of the cylinder head combustion chamber has been increased; resulting in a lower calculated static compression ratio number, witnessed as a lesser pressure result on the cranking compression tester gauge face.

viewtopic.php?p=803393#p803393

Always continue cranking the engine over during the compression test session until the needle climbs no higher on the gauge face.
Forget the ages old advisement to count to 10 compression strokes. Why? I've observed multiple times during the compression testing sessions with my '75 GL1000 engine, as the individual cylinder pressures are reaching higher numbers, the gauge needle will twitch back forth a few psi (5-10 ish) until the needle finally stops climbing on the gauge face. Then I release the starter button.

@ericheath
I've longed to perform the testing procedure to measure cc's of the GL1000 cylinder head combustion chamber with an NGK D8EA spark plug, fully installed.

Then, after removing the NGK D8EA spark plug, perform another cylinder head cc's test with a proper checked 14mm compression tester hose adapted down to 12mm spark plug hole threads diameter to compare the difference in liquid testing fluid displacement volume (cc's) between the correct and incorrect spark plug hole compression testing adaptors.

I have an old GL1000 cylinder that sorely needs to be prepped for this project but haven't invested in a clear square of chamber covering acrylic sheet. Also need a graduated burette for the testing liquid.
They are expensive...

[ericheath]

My Harbor Fright tube held 10.1 cc’s of liquid. I believe a 1000 combustion chamber is around 33cc’s. It would drop compression a lot.

My hybrid 1200 would put 185psi to the same gauge after shaved heads and advancing the cams 4 degrees. If my guesstimate is correct that would have made mine 230 or 240psi, which would have gone poof real fast on pump gas , wouldn’t it?