From:Barry Brown e-mail:oldmill@kingston.net
Subject:RE: New cylinders and heads on Cannonball Date:Wed Nov 7 07:40:05 2012
Response to:4353

Sounds great. Which bikes had special ground cams and counterbalanced
cranks and are these items going to be available too? Were these engines
tested on a dyno to compare before and after and if so what effect did the
different cam grinds have?
----- ORIGINAL MESSAGE FOLLOWS -----
New cylinders and heads on Cannonball:
New high performance cylinders and heads were used on the following
motorcycles:
Byrne Bramwell’s #32
Mike Fockler’s #65
Dale Stoner’s #99
New high performance cylinders only were used on:
Clyde Crouch’s #31
Motors in each motorcycle were set up differently to test parts. Coast 4’s
built all motors.
My motor was 100% stock except for the cylinders and heads. I used a
Schebler DLX 84 carburetor with .937” venture. This carburetor is believed to
be the original KL carburetor by some people.
All new cylinders and heads on all of the bikes performed flawlessly. There
were other issues with some of the motorcycles but no issues with cylinders
or heads.
These new cylinders are identical to originals on the outside. The inside has
been changed to raise the compression from 4.7 to 5.7. The cylinders use a
domed piston similar to a KL design. The exhaust valve and port are smaller.
This increase velocity in the port and scavenges the exhaust out of the
cylinders more efficiently. The more efficient removal of exhaust also makes
the engine run cooler.
We decided to develop a new head because the original head flow tested so
poorly. In the original design the air has to flow around push rod and bolt
columns. The air is directed up and down to get to the end cylinders. End
cylinders receive 40% less flow than the center cylinder.
The new head we designed all cylinders flow within 2% of each other. When
using new cylinders and heads together all cylinders flow 30% better than the
original center cylinders. Obviously, flow bench tests and real world differ.
But these bikes out performed stock KJ’s by a large amount. At first glance
the new head looks stock. The right side is nearly identical to an original.
The left side is where the differences can be seen. The only way a person can
see that a Henderson KJ has the “Cannonball Special” head is to knell down
close to the motorcycle and look under the gas tank on the left side and look
for the log style manifold. The carburetor mounts in its original location
except it protrudes 5/16” out further.
The cylinders and heads have been designed using professionals SA Racing
and New Class Iron, worked together developing the combustion chamber and
port design. SA Racing did all the flow bench testing and directed New
Classic Iron in revisions to develop a casting with better air flow. New Classic
Iron made the patterns to cast all the heads and cylinders. The tooling and
machining of castings was also performed by New Classic Iron. Professional
laboratories were used to select proper chemistry of the cast iron and were
also used to select aging and annealing processes.
High performance and stock KJ cylinders will be available in January, 2013.
Cannonball special heads will be available hopefully in February, 2013.
Pricing has not been established, but will be posted in a few weeks.