I have a question for you, not sure if you can answer it. Australia has such strict emissions laws, how does Scotty Cox get by with building the custom bike that he does? There is nothing stock about any of his bikes.
I know this all to well as I am still building an old school bike in my garage, so here is a short rundown:
1) The bike is a limited custom but still has to comply with the ADR (Australian Design Rules).
2) The front axle can't be more than 55CM from the centre of the neck.
3) The bars can't be more than 38CM higher than the lowest point of the seat (no ape hangers obviously)
4) Headlight must have E4 marking and be for left side of the road use.
5) Indicators must be amber and have E4 marking.
6) Stop light must have E4 Marking and at least 38CM above the road. (I'll have to look the height up again but it's somenthing like that.
7) The mount for the number plate must be horizontal and make the plate visible for about 60 degrees off axis. (I'll need to double check the latest on that).
8) The frame must come from a recognised frame builder and have a MSO.
9) The engine must have a MSO
10) The brakes must meet ADRs.
11) The exhaust must meet ADRs.
12) The mirrors must be ADR compliant.
13) When finished the bike must be "engineered" by an engineer registered with the RTA/RMS/ Service NSW (in NSW, I don't know about other states).
So the engineer I have charges AU $4000 for his inspection. The bike still has to get another inspection to get a "blue slip" which double checks that the bike matches the engineers report before you can register the bike.
My engineer gave me a few tips:
A) Get a late model HD exhaust and make sure it's on when I inspect it. Also make sure you have a closed style air clean on for inspection.
B) Use the same brakes as another custom that has already been passed.
C) Make sure all your lights are E marked.
D) Make sure your bars are not above the limit.
E) Put some late model HD mirrors on.
F) Make sure your front end is not past the 55CM limit. (My front end turned out to be right on the limit but if it was not then I was going to use some 3 degree neck cups put in backwards to bring the front end back to be 55CM or less).
Once it gets through then you put the real exhaust, real bars and real lights on and be careful to avoid the cops. I have made some special baffles for my "real exhaust" to bring the noise down to a level that I can take. Should also fly under the cops radar, fingers crossed.