Ok - before I start this update I'll state upfront that won't be able to make racing in 2012
but the good news is that I have the go ahead for 2013
This is a long post as I have had a few things on the go and they are all just starting to produce results now, which means in 2013 I should have a pretty mean machine!!!
1) CFD Modelling
After many many hours of banging my head against free OpenFOAM CFD software I am now getting sensible results with my 3D scanned Vespa
I am able to calculate drag and how much power I need at what speed. I can also visualise the problem areas. I've evolved the motorbike example, which comes with the software, from 20 minute "toy" result, to something that is way more accurate that runs over 24 CPU hours (with more accurate runs planned). I can do a decent run over night, so this gets me a few hundred virtual salt runs before '13 and so I can tweak the body work and make it perfect
2) Bits and Pieces
The next part of the puzzle was producing the said bits above (plus also that reed manifold extension mentioned). Last week I took delivery of my CNC set-up
Jeremy who fitted the KDX head, kindly retrofitted steppers to my mill head. So now I can model the bits in CAD, pop them on my virtual Vespa, race it on my virtual salt track, and then use the CNC to help produce them!
3) Gearing and better manifold
The last dyno run told me I needed taller gearing and/or higher rpm. So I rebuilt the bottom end with a taller 4th (which wasn't available to me a few years ago) and built a new shorter, free flowing manifold. I dyno'd the scoot also last week and using the CFD results and the actual power results I should hit 105 mph!!!
The bad news was the manifold had an air leak, the good news is we found lots jetting improvements with the old one (and more to come with more jets).
Below is the dyno measured rear wheel power plotted against the calculated power I need to overcome drag.
So I have a lot to keep me busy preparing. Especially since I have now changed my target. It was 100mph, however Tony O'Brien in the UK just got 100.5mph. So I am now aiming for 107+mph with better aerodynamics and some radical engine modifications (more on that later when I have something to show for it). Oh - am I planning a Philip Island trip this year to confirm top speed and get used to riding it at those speeds