This post is a continuation of a thread that starts here.  The previous post in the series (Heads and Cylinders to Machine Shop) is here.

Oops.  How did that happen?

Well, first off let me say that unfortunately, there are no pictures to share with this experience.  Momemtum got the best of the situation and it just didn’t happen.  Sorry.  I’ll add them as I can for the benefit of those not reading this in real time.

Machine Shop Observations

After complete disassembly we found that both of my heads were in really great shape with the exception of the huge volume of carbon built up on the combustion chambers and valves.  We blasted the heads, cleaned up the seats and valve faces and put them back together.

The cylinders were checked with a bore guage and found to be within 0.001 both in round and taper.  We broke the glaze on the and its re-assembly time.


You need a top end gasket set at this point if you don’t already have one.  The first thing I did when I got this bike was to order a complete seal and gasket set for it.  Sooner or later you’re gonna need it.

What Not to Do

I grabbed my gasket set and proceeded to pile a bunch of parts onto the kitchen table.  Reasured the little lady that this would not turn into a complete motorcycle before leaving the room like it did back in 77.  Filled my coffee cup and set down to concentrate on getting things ready to go back together.

Unless there is visible wear or you have reason to suspect that your rocker boxes are in need of repair we can put the covers back on the heads.  I checked mine and found that there has been a bit of machining done to remove extra weight from the rockers themselves.  Also a bit of aluminum was machined away on the rocker covers themselves.  Somebody really want to trim every ounce they could from the valve train and overall weight of this bike. 

I grabbed a head cleaned the gasket surfaces.  Same with the rocker cover. Slid the gasket over the studs on the head and aligned the rocker stud holes with the studs and slid the rocker down.  It went almost all the way without any resistance.  The last little dab required a little encouragement from my fist tapping on it.  “That was pretty easy.” I thought.  Then I realized I had commited the ultimate in idiot mistakes.  I had put the front rocker cover on the rear head.  THIS WILL NOT WORK.  The rear rocker has two oil lines that attach to it.  The feed from the case and the overhead interconnect.  With the head like I had it the only oil line attachment was facing backwards.  The cover had to be removed and replaced with the right one.

Remember that last little bit of resistance going on?  Coming off it was a LOT worse.  I tore the gasket while trying to get the damned thing off.  That really bummed be out thinking I would end up having to go to St. Louis to get a damned $2 gasket.  Had to use wegs of wood to get the damned thing off.  I wasn’t fun and had a lot of bad words to say while getting through it.  Don’t do it.  Examine your parts and think.

Good News ala Black Diamond Harley Davidson

A phone call to a few local parts places found only complete top end gasket sets.  No loose rocker gaskets.  Low and behold, the local HD shop actually had one in stock!  Back on track.  Have my bro Bill grab one on his way down.  He comes right past it.

Put the other head together and wait for him to get here.  Start to see why I didn’t get many pictures?

After his arrival I finished assembling the rocker covers onto the heads.

Base Gaskets and Cylinders

Clean the gasket surfaces on both your engine cases and the cylinder to insure a good seal.  Before putting on the cylinder it is a real good time to tighten up anything that you can see in the engine and transmission area.  Check the torque specs before just blindly cranking everything as tight as you can get it.  It will be a lot easier now than when the top end is back in place.

Wash the cylinder out with a mild dish soap solution and dry it with a cloth.  Do not apply any oil to the cylinder.  Under the advice of a local race shot guru I elected to use a method different than I ever have berfore when it comes to prelubing rings.  In the past I always oiled the hell out of my rings before assembly.  Mr. Guru says not to do that.  Instead apply a few drops only of very light oil to the ring grove in the piston and spread this very light film around the groove by spinning the ring.  Repeat for each ring set.  Do not get any oil above the top oil ring.

Find the rear cylinder base gasket.  It is physically larger then the front gasket.  Notice the oil passage hole in the gasket and on the cylinder and case.  Be sure that the gasket hole is correctly aligned with the holes in the cylinder and case.  The manual says to have the flywheels at bottom dead center.  I like them at about half mast.

Apply a thin coat of engine oil to the skirts of the rear piston.  Don’t get any above the rings.  They are basically dry but the piston skirts are prelubed.

If you have one, now is the time to place your ring compressor around the rear piston.  Make sure that the grooves in the rings are spread around the piston before compressing them in any event.  If you  use a ring compressor be sure to over tighten it.  You want it loose enough to slide easily down the piston as the cylinder slides down.

I my case I use the finger nail method.  Slide the cylinder down over each ring individually.  Don’t try to get them all at once.  With the back of the ring under the cylinder wall use your finger nail to compress the ring into its grove while sliding the cylinder down.  Repeat on the opposite side of the pistion and the first ring is in.  Repeat for both of the remaining rings.

It isn’t very difficult to do.  If you are having a big problem take off the jug and check that your rings are installed correctly.  The oil rings can be a bit nasty to get on right some times.  Your cylinder should slide right down until it reaches the base studs.  Carefully align the studs and finish sliding the cylinder onto them until it rests on the base gasket.

Install a triangular base washer onto each stud.  Notice that these have the word “UP” stamped on them.  Be sure you can read this when they are installed.  Install the base nuts finger tight around the cylinder base.  Torgue them to specs (32-40 ft lbs.) by evenly tightening the bolts a little at a time in a cross pattern.

Whether you install the rear head of the front cylinder next is up to you.  I installed the cylinder first.

Repeat the above procedure for the front cylinder.  Note that there are two oil passages through the front gasket.  One of them is most commonly not used and doesn’t mate to anything in the cylinder or case.  Make sure the one you have does though.

Installing the Cylinder Heads

More to come….  Gotta go play poker.

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