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[11 CVO Convertible]

Several things...........
I've cc'd many sets of 110" domed pistons like you show in your pics. They ALL have come in at 11 cc.
Also, if you're checking your deck height beyond the valve pocket area(your bottom pic), there's more room for error   than over each end of the wrist pin.
John

Thanks for the incite!  I'll error on the side of caution and calculate my compression based on your 11cc's.  You appear to have a more high tech method for cc'ing pistons than I do.  I measured my deck height  at the wrist pin.

[HILLSIDECYCLE.COM]

Collin,
We too, have cc'd those pistons, and they've also come in at 11cc's, as John has already made mention of.
Looks like you are coming along real good!!
Scott

[11 CVO Convertible]

At what point do I need to worry about piston to valve clearance from milling heads, decking cylinders, and thin head gaskets?  I'm not worried about the valves hitting the bottom of thr relief, but rather the valve hitting the backside of the relief at the outer part of the piston as the piston keeps moving up due to the machine work.

[HILLSIDECYCLE.COM]

You should have PLENTY of room as that cam has a relatively low TDC for what it is, but in order to double-check, a little clay will tell the story.
Scott

[11 CVO Convertible]

I spoke with Mike Lozano from Lozano Brothers Porting today.  He said he would be able to get the heads and cylinders in and out in a couple days.  I plan to drop them off on Saturday.  I'm torn with how much to take off the cylinders for fear of having piston to valve issues with the non-relieved part of the piston.  For every .010" that is shaved of the head and deck of the cylinders, the valves gets ~.005" closer to the back of the unrelieved area (assuming an approximate 30° valve angle).

I think I'm going for broke and shooting for .022" cold quench (pistons up .005") and a chamber volume of 93.5.  That should put me a little over 11.25:1.

[11 CVO Convertible]

The heads and cylinders were dropped off to be machined.  I've had several days now with nothing to do, so I've been researching compression ratios that others are using successfully without detonation.  On harleytechtalk.org, there are SEVERAL builds with cranking compression well over 220 psi.  Most all the bikes are heavier touring bikes, and all say that there is not issue with detonation even in heat on extended trips.  I'm willing to gamble a little here, so now I'm thinking bumping up the squeeze to 11.5:1 and running really tight quench to help mitigate detonation.  That would mean running my quench at .020" with the pistons .007" out of the hole and setting the chambers at 92 cc's.  This would put my cranking compression at 210.7 psi.  The bike stock was around 205 psi, so I'm really not pushing it too much more (in my mind).

Any thoughts???

[HILLSIDECYCLE.COM]

Might be a tick too much in that Texas heat.
Scott

[11 CVO Convertible]

I got the heads and cylinders back from Lozano Brothers yesterday.  I ended up setting the pistons at 0 deck height and the chambers at 92cc's.  This should yield 11.33:1 compression with a quench of .027".  When I was at Lozano Brothers, I spent about an hour talking with Mike as he showed my around their place.  Extremely knowledgeable guy (that's a gross understatement) with both cars and motorcycles.  He also does tuning, so I'll be taking my bike to him to tune instead of hauling it all the way to Dallas.

I started today looking at the heads and noticed that I could see light at the valve seat.  I took them apart only to see that the intake valves only seal when oriented one way and the exhaust valves appeared to have the ceramic coating on the seat.  I lapped all the valves until they sealed tight and put them back together.

The primary got the new Evolution Industries 49 tooth billet clutch basket installed.  To make this work with out noise, I cut the rear part of the tensioner off as instructed on Evolution's website.  I also installed the Barnett clutch spring and the AIM lockup clutch hat.  I'm lacking oil, but I plan to run Mobil 1 ATF in the primary.

The engine went together pretty smooth after the valves were lapped.  Prior to putting on the S&S Throttle Hog, I took some pictures to show the plenum difference between the 50mm stocker and the Throttle Hog.  The rocker arm supports breather oil return holes (under the umbrella valve and sponge) were drilled out to a #38 (.1015") to help with oil control/vapors since I'll be keeping her wound up more.  In the picture below, only the bottom hole was drilled for comparison.  

I finished the night by getting the rear cylinder's pushrods adjusted and the Wood lifter preloaded .125".  I'll hop on the front cylinder tomorrow and degree the cams to see where there were ground.  

[Lever]

looks great  .....  want to give you some info  that I had to do on my bike  ....  had to buy a spacer that goes between the primary cover and primary it self also had to grind out some metal area to allow the weights on the lock up to have room to work

[HD Street Performance]

Once again a very detailed good job, good choices and parts that should play well assuming the pipe is there.

This statement is a red flag IMO
"I took them apart only to see that the intake valves only seal when oriented one way"

No a fan of lapping to fix a concentric issue which is what you are describing. Pretty far along now to go back.

[11 CVO Convertible]

Once again a very detailed good job, good choices and parts that should play well assuming the pipe is there.

This statement is a red flag IMO
"I took them apart only to see that the intake valves only seal when oriented one way"

No a fan of lapping to fix a concentric issue which is what you are describing. Pretty far along now to go back.

Very true and I wasn't happy about it having to do it.  I have to believe that Scott had everything right before they went to Swain.  I think the heat added in the process might have warped some surfaces or it was just the coating that wasn't even on the valve seat.  I couldn't pull the valve all the way out to see what was going on as I didn't want to damage the valve seals.  Lesson learned....if the coatings are worth doing again (and I'm not convinced just do to the issues they have caused already) the valve job needs to be done after.

Plus, if this motor doesn't make the power I want or starts having issues, it will give me a good reason to start on the next motor faster.  As nice set of B2 or Hurricane heads worked over by Lozano Brothers mated to a 117"....

[11 CVO Convertible]

looks great  .....  want to give you some info  that I had to do on my bike  ....  had to buy a spacer that goes between the primary cover and primary it self also had to grind out some metal area to allow the weights on the lock up to have room to work

AIM claims theirs will work with the stock derby cover....that's why I went with theirs and not some others I found.  Hopefully that is true.  I'll keep you posted.

[HD Street Performance]

Lesson learned....if the coatings are worth doing again (and I'm not convinced just do to the issues they have caused already) the valve job needs to be done after.

There you go, I agree
If it doesn't make power just fix the valves and seats and I betcha it will haul ass.

[11 CVO Convertible]

I got everything finished up today.  I installed the Oil Bud oil cooler.  Hopefully will keep some of the heat out of the oil.  I turned over the motor a few times with the rear wheel by hand.  After that, I cranked it over several times. Everything sounds good, so I'm ready to get this running and tuned.

[HILLSIDECYCLE.COM]

Looking good Collin.
Scott