1st August 1950

Mr. Rollie R. Free
1740, No. Gramercy Place
Los Angeles 28,
California,
USA

Dear Rollie,

I thank you for your letter of the 28th of July and am
now pleased to inform you that your "Black Lightning" model has
very successfully past its speed tests.

As before we only had a short 1,600 yard aerodrome
runway to use, but in this space the machine , running on a 3.1 to 1
gear, easily reached 135 before being changed into top and then
proceeded to accelerate very hard in top gear before it had to be
cut.

The tester , who is very experienced with our "Black
Lightning" models, formed the opinion that the machine was very
definitely considerably under-geared and would pull a very much
higher gear quite satisfactorily. Since the engine appeared to
be developing its main power at over 6,000 R.P.M. , when a distinct
megaphone effect became apparent in the higher revolution range in the
form of a greatly increased surge of power, we have little doubt
that this machine is capable of traveling very much faster than
the last one which we sent to you.

At this point I must interject a very serious note
of warning because we have fitted our latest type of cylinder heads
and carburettors and large inlet valves as used in the single
cylinder T.T. models this year, but due to the fact that we have
had no chance to carry out the necessary experiments with a twin
cylinder model,   e have not dared to fit our newly designed big
end which will stand almost unlimited revolutions from the engine.

Contd.

A failure of the crankpin at very high speeds was too
dangerous to be contemplated, so we have had to play safe
and fit the same type roller big end as you had on the other
machine and as we fit as standard to all models.

This big end, wilst very good at all usual speeds
has a very short life at speeds over 6,400 R.P.M. It is
therefore essential that you should gear the machine so that
you will not exceed 6,400 R.P.M. on top gear, and that you
should watch your tachometer and change up in plenty of time
before the danger mark is reached.

The change over to the new type big end when we
have had an opportunity to test and prove its security in the
twin cylinder engine, is relatively simple for any precision
machine shop, and we hope in due course to be able to send
you the necessary new crankpin parts, together with a drawing
showing the necessary alterations to your flywheels so that
by next year you can have the machine equipped with the new
type big end.

We shall be shipping the machine through our usual
Shippers, Messrs. Morison Pollexfen & Blair Ltd. , 90, Fenchurch
Street, London, E.C.3., and the transit foward from New York
will be handled by their New York Office, Messrs, J.J. Murphy
& Co. Inc., South Ferry Bldgs, 44, Whitehall St. No doubt
Mickey already knows quite well their Broker in Los Angeles.

The machine has not yet actually left the works
but we are hoping to have it away within the next two or
three days.

There is one other word of warning I must utter,
this being that these special cylinder heads fitted for the
sprint mile are still in the experimental stage and we cannot
rely on an exhuast valve life greater than about 250 to 300
miles. This is a matter that is under going investigation
at present, but time has been too short to arrive at any
conclusion due to the extreme pressure on all departments
of our business at present. The machine has already covered
some 125 miles or more on test but, of course, most of this
has not been at racing speed. you should therefore be
perfectly safe for at least another 120 miles before running
any risk of valve trouble, but meanwhile we are having two
more valves prepared and hope to pass these foward to you
within the next few days so that should you have to carry

Contd.

---

out a great deal of practice you can change them before you
run into trouble.

For any duration records that you may decide to
attempt we are enclosing two standard type "Black Lightning"
heads and two smaller, standard size, carburettors, and these
must be substituted for any appreciable distance runs. For
this purpose, of course, they will be more than adequate
since you will be running at very much lower speeds.

I am writing to-day to the A.C.U. to ask what
progress is being made reguarding the permit for the A.A.A.
to check your record attempt.

I am very sorry for the delay that has arisen
but we have been simply swamped with work. Sales output
and deliveries are breaking all records and there are so
many special parts that have had to be made for this machine
that the Tool Room, which is already overburdened with work,
took longer than was expected. However, it is now, as
mentioned earlier, complete, and I trust that it will arrive
quite safely in time, and that every success will attend your
efforts.
 

p.s. The machine is being crated with sprockets
that give a high gear of 2.43 to 1     also alternative
sprockets for lower gears being crated with sprockets
that give a high gear of 2.43 to 1     also alternative
sprockets for lower gears