Author Topic: Knuckle top on Pan/gen Shovel/cone Shovel lower info.  (Read 5172 times)

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Offline Lyle

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Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« on: September 14, 2012, 11:36:16 AM »
 I decided to hold off on this project for a variety of reasons. I still plan on doing the "budget"  Knuckle top on cone Shovel bottom in the future. Here is some good reading for those considering the conversion.

http://knuckleheadtheology.blogspot.com/2010_06_01_archive.html

Offline Deye76

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #1 on: October 31, 2012, 05:01:28 PM »
Hope you can do it sometime. I'm planning a Pan over Shovel cone nose.
East Tenn.
2014 CVO RK, 2015 RGS, 1992 FXRP

Offline stroker800

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #2 on: February 05, 2013, 07:17:13 PM »
 My buddy races a 114" knuckle,,genny shovel bottom end,,shovel cyls,,knuck heads,, evo roller rockers...My motor guy did all the work..
Dave

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #3 on: February 05, 2013, 07:31:39 PM »
 Very nice. A company in Germany is making aluminum heads for Knuckle now. I am going to pick up a set this summer. Build a 100+ inch cone or gen motor around them. Should be interesting.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #4 on: June 16, 2013, 10:01:43 AM »
Well, 1st off Happy Fathers day to all the dads here! Secondly, this project is back on the bench!

I have managed to locate a 15 year old, unused set of S&S Sidewinder 3 5/8 Knuck cylinders and pistons. If anyone is familiar with these they are Pan cylinders modified for Knuckle heads that S&S built before they aquired FHP. Many +++ to these and a couple - .

+
Strong
Have oil return cast into the cylinder solving my oil return problem
Same height as stock Shovel/Pan cylinders (5.330) which solves many of my valvetrain issues!

-
Need to re-locate one bolt hole in the Knuck heads.
5.330 cylinder height limits stroke options unless I use stroker plates.

With this said, I will be running some AFM 3 5/8 cone cases, MOCO or AFM 4 1/4 wheels to make it an 88" motor.

One set of the v-twin, S&S, or the German heads. I would consider some MOCO heads but its hard to find a good set and it wouldnt sit right with me modifying a good set for the Pan head bolt pattern. In a perfect world an already modified MOCO set would make itself available when the time was right.

Ill post up some pics when the cylinders land at my doorstep in the next week or so.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #5 on: June 20, 2013, 07:08:03 PM »
Here are those cylinders.




The little nipple hanging off the side is tapped into the oil return in the cylinder.
I am working on getting a set of heads as I type. Have some feelers out and some bids in. It may take me a little bit to get this thing built but the ball has started rolling. Stay tuned.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #6 on: July 20, 2013, 06:16:13 PM »
Update: I am waiting on the German company to cast and machine up some more of their aluminum heads. I was in the middle of buying some good MOCO take-off heads then decided not to ruin some already hard to find vintage parts so I passed. I am expecting an e-mail from Germany within the next couple weeks. Ill post more pictures when they get here.

Offline panic

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #7 on: August 27, 2013, 07:53:47 AM »
The knuck valve train needs more mods than are mentioned in that article.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #8 on: August 29, 2013, 01:04:33 PM »
@Panic, agreed. The valvetrain issues I have encountered not mentioned have been solved quite simply. The cam I am using is a custom Leinweber Knucklehead performance grind on a Shovelhead blank. The pushrod tube angles or lack thereof have been addressed at the lifter block. As far as lifters and pushrods I am using Crane adjustable mechanical Shovelhead lifters with custom Knucklehead Pushrods. All these mods combined keep the geometry correct.

Offline panic

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #9 on: August 29, 2013, 10:17:51 PM »
I was surprised to see that they discussed which tappet blocks to use and why, but left out an important warning:
The "clock" position of the tappet bores with respect to the cam lobes are different between the knuck vs. pan/shovel cams. A knuck cam (not a knuck grind on a later cam) should be used only with knuck tappets, and vice-versa.
BTW: a similar error occurs when swapping Evo cam, tappets and blocks into a shovel: the cam events don't match the nominal figures. No, this can't be adjusted out or re-timed with a multi-key drive gear.
The other headache is minor in that it's a function of valve lift; if using the original knuck rockers and the lift is kept close to stock (up to perhaps .400"?) IDT any work is needed. However - as the lift goes up, the geometry between the rocker levers and the stem is upset.
Assuming that all component dimensions are either stock and nominal or otherwise corrected for, the valve-side lever should rest (valve closed) higher than stock by 50% of the lift increase. E.g., if .345" (quoth Palmer) is OK, .445" lift needs the rocker to sit .050" higher on the stem tip to maintain the same geo.
Since moving the shaft is out of the question, a lash cap looks good here.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #10 on: November 25, 2013, 06:16:11 PM »
Well the Germans must have run into an engineering problem with their aluminum heads. All this time Ive been waiting to get my hands on a set may have been a blessing. I received an e-mail from them yesterday apologizing and they would get back to me in Jan-Feb 2014 when they release their newly engineer'd heads. If they dont get them done and figured out by the time im ready, ill will be using S&S heads.

 Im also shopping for some S&S standard bore knuckle cylinders. Going to bore them for 3 1/2 pistons to run on a MOCO 80" Shovel lower that I already own. Not buying new cases and flywheels saves me a bunch of money that I can use to finish buying S&S parts for either set of heads.
 
The NOS S&S 3 5/8 cylinder kit will go on the shelf for the next adventure or I will sell them to someone with already converted Knuckleheads.

Offline panic

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #11 on: November 25, 2013, 09:53:19 PM »
Re: "the Germans must have run into an engineering problem"

It may one of those that plagued prior attempts.
The easiest model is to simply reproduce the original head in aluminum, because stock appearance is a strong sales point.
However, they discover that cast aluminum isn't as strong as cast iron, especially as to the threaded holes and structural sections that provide stiffness and rigidity. Making the aluminum thicker helps, but immediately interferes with many other areas or components line the guides and lower covers.
The greater thermal expansion of aluminum means that the guide holes will move up and away from each other as the engine warms up. Adding metal? There's nowhere to go without changing the shape of the casting.
I would guess the worst thermal distortion is how the shafts and boxes attach. The rocker shafts mount in 2 planes (unlike any other H-D): the left side passes through the head's vertical "ears", which move up when hot, elevating that end of the shaft. The right side of the shaft passes through the box casting, which will not rise by nearly as much. The box itself bolts to horizontal ears extending out to the right side, which moves out (not up) with expansion. These ears are too weak even in cast iron, and should be stiffened from below with a big strut or fin but no one remembers to do this until after it breaks.
There's a temptation to change stuff in the boxes to use higher ratio rockers (1:1 ratio was actually very common in those days, Gold Star etc.), until they realize how much that raises the price and delays development.

Summary: it's harder to do than it looks and except for the weight saving (on the bike, and also shipping cost) there's no advantage.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #12 on: November 25, 2013, 10:07:34 PM »
All great points. I do plan on running this motor a lot. One of my biggest concerns was the valve seats. If they aren't freezing them and just pressing them in I'd be worried about dropping one on one of our warm summer days here (118 deg). Thanks for putting my mind to work. May have saved me some headaches down the road.
So, S&S here I come.

Offline fueliebob

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #13 on: July 13, 2014, 11:37:18 AM »
Lyle,

Is the lip on the top of  those cylinders smaller than a pan lip. Back in the day I had a set of knuckleheads modified to relocate the bolt hole for pan cylinders. I also had the machinist turn the head so the wider pan lip would fit. That effectively lowered the cylinder height so the compression was a beast on that motor. It also had 2 right side VL flywheels, so it was an all Harley stroker at 80" back in the 74" days.

Offline Lyle

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Re: Knuckle top on Pan/gen Shovel/cone Shovel lower info.
« Reply #14 on: July 13, 2014, 06:34:05 PM »
The fire ring has been machined down to about .030 tall. S&S left just enough to center the head gasket. I am still working towards putting this thing together. Money and a some hard to find 3 5/8 copper Panhead head gaskets just wont see it completed quickly. I have some of the teflon style gaskets but I worry about the lack of thermal transfer from head to cylinder with them.