2015 Update
We
are off to the salt today and I thought it time for a long overdue
update on the Big Velo.... ..... Due to rules we now have to run
tubeless Moto GP tyres, and the easiest way was to use forks and mag
wheels off a modern bike.... CBR 600 Honda was the cheapest donor I
could find.... this required further modification to the swing arm and
widening the final drive etc etc etc .... it never ends....sorry it will
not quite look right but over $6000 for custom tubeless spoked rims was
a bit much.......the engine has had terminal overheating and a
tremendous effort has been put into managing cylinder head temps...also
power is reaching a level that the clutch has finally had to be upgraded
to an 11 plate unit .....surprisingly as it turned out this was a
relatively simple job....... and as I do not have to find neutral at the
traffic lights and only have three gear changes it should free just
enough for the job at hand....The pic of the three engines are a std 500
, the 700 and the supercharged 650 Mk IX.... for interest the std 500
weighs about 33 kg but the 650 weighs almost 50 kg !!.... the extra oil
pump is from an early MOV....
The
engine is yet again an interim development unit cobbled together out
of the spare engine I took to Bonneville a few years ago and last years
183 mph engine and various bits and pieces from around the shed and a
heavily modified Viper head ....plus a host of new and old
bits.....What with the engine changes and the new wheels tyres and
suspension I really need a testing year to ensure it is a stable package
before trying for the 200 mark and as such the engine is more of a test
unit to prove some of the modifications and theoretical solutions to
problems I have encountered in the effort to get the sustained 110 hp
at the wheel (135 at the crank) that I need to get the magic
200........whilst that sort of power is quite possible now the engine
is not yet capable of running sustained at that level for the necessary 5
miles..... here I might point out an interesting point.....probably
the most powerful ever individual air cooled cylinders were on the big
radial aero engines of WW2 ......120 to 150hp per cylinder at the
crank......the Wright 3350 engines of the B29 often overheated and
caught fire on take off..........this might help put some of the
challenges faced with the Velo in perspective !!!
It
may seem that we have just easily push the speed up each year, however
around a 1000 hours of combined effort from our team is required to
achieve this and we are a much smaller group than Hall Green had..... so
the aim for 2015 is really just a consolidation phase....do not expect
too much.... the hill is getting very steep !!..... as the speed
doubles, the drag squares, the horsepower requirement cubes and the time
effort and money is raised to the fourth power !!!
I
thought you might like a pic of the Mk IX engine !!!!!
...................... a water cooled head would make it oh so
easy........ but then it would not be a Velo................ unless it
was a side valve flat twin !..... Hmmm....maybe that could be next !
