The
story of the Superpan
Part
1
I first saw Ronnie Breuer's "Superpan"
parked in the grass at the drag races in Lommel last year. I took some
pics and was very impressed by all the homemade parts and original ideas
used on this machine. One of the first things I noticed was that there
were almost no cables anywhere. And where was the carb? Upon closer
inspection it seemed that almost everything was handmade, including
the cylinder heads!
I put the
pics on my website with a short message that I wanted to speak to
the builder, and a few months later I received an E-mail from Ronnie
Breuer who invited me to come to his house to take some more pictures
and do an "interview".
How it
all began:
A couple of years ago Ronny had a very cool Swedish
style Shovel chopper (see photo), and a nice little workshop behind
his house where his mates and him worked on their bikes. After
2 of his mates bought Panheads, Ronny decided he wanted one too;
only he wanted something very special….
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He sold his Shovel chopper to finance the new project and bought
a professional vertical milling machine so he could make his own
cylinder heads. The design of his heads was the result of studying
original Pan-heads, aftermarket STD Pan-heads, Evo-heads and some
tuning books he found in the library of the nearby Technical University
of Eindhoven.
Ronnie made all the necessary drawings with a 2D CAD program (Autocad) |
The RB heads use Evo valves and rockers, bathtub
shaped combustion chambers and most importantly raised inlet ports.
(The biggest design flaw in original Harley heads is the shape
of the inlet ports) Ronnie also drastically improved the cooling
of the top of the heads by incorporating a large cooling channel
through the valve covers into the center of each head.
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The connection between intake manifolds and cylinder heads was
also beefed up by using 4 bolts per head instead of the stock panhead
clamps. Anyone who has ever made his/her parts with a vertical milling
machine knows that most of the time spent goes into planning, positioning
and measuring and that the actual time spent removing metal is relatively
short. In Ronnie's case this was no different. |
Starting with a big block of UN-T-633 aluminum,
he first milled 4 slots in the sides in order to attach the aluminum
to the bed of the milling machine in such a way that he could
remove a lot of material from one side of the block without the
clamps getting in the way.
The next step was machining the head gasket face and the holes
for the headbolts.
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The holes for the valve guides and seats came next, after which
RB machined the rough outline of the heads. After these jobs were
done, RB removed the head from the bed of the milling machine and
remounted it on angled table to machine the surfaces for the intake-
and exhaust gaskets. Of course every time the head was removed from
the milling machine it had to be pain- |
stakingly repositioned so the machined surfaces
ended up accurate in respect to one another, so the order in which
the surfaces were machined was carefully planned in advance to
minimize the number of times RB had to do this. The next job was
cutting the cooling ribs, now this really is a great way to make
a mess in your workshop. Judging by the photo's Ronnie must have
been finding bits of aluminum everywhere for a quite a while.
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At this point I must remind you that RB's milling machine is not
a computer controlled marvel like one can find in the more modern
factory's nowadays, but operated by manually rotating 3 handwheels;
one for X (back and forward), one for Y (left and right) and one
for Z (up and down). What this means in plain English is that if
Ronnie had for instance turned one of these wheels left where he
should have turned |
right he might have had to start the whole thing
over again from scratch! Talk about stress...... Anyway, apparently
he made no such mistakes and after 250 hours of work Ronnie eventually
finished the front cylinderhead of his Superpan. The photo on
the right gives an exellent view of the Evo rockers and the large
cooling channel to the center of the head
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Where one original Panhead had two lower rocker blocks, two upper
rocker blocks, RB's first head was a one piece unit. In the photo
above you can see the difference between the stock system in the
corner and RB's modern version. The photo on the left gives a good
view of the finished combustion chamber. |
Mounted on the engine and fitted with the tradional
Panhead valvecover it is a magnificent piece of work. Just wait
untill you see the rest of this bike; you ain't seen nothin' yet!
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NEXT
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