This seems to be the question of the week around here. The answer is basically the same. I would start looking at other bikes on the net or in person to see what kind of look that you like and go from there. E-bay will be your friend. Depending on your capabilities, anything can be made to fit. Mostly, just get after it and figure that you are going to try some things and see what works. The point is that you will not be able to afford to have someone do it for you. Get in there, ruin some parts and wreck some stuff on your first try. I still say collect up some parts bikes and make freinds with your local salvage yard if you can. We appear to really have 2 groups on this board although there is overlap. We have racers and street guys. What is the hot setup on the track is not what may be best on the street. That being said, I would suggest that everybody should go racing, it is way too much fun.
Now we get into the opinion phase of the answer. The CM400E is what it is, a fairly slow overweight vanilla kinda Honda. I don't know what kind of custom seat you have on it but that and the tank shape will determine the look you want. Consider bodywork parts from the CB400T Hawk or the 450 Hawk they may fit(Geeto67 jump in here). You are not going to get much performance out of this bike no matter what. A full race engine would cost you thousands and still be slow. I would look at putting a 2 into 1 exhaust on it to get rid of that heavy stock system, do something about the intake, and work on suspension whells brakes and tires. You should be able to spend plenty on thaose things. If you have any particular questions about specifics in any of those areas ask away, there seems to be plenty of expertise here.
Good Luck,
Ken
AHRMA 412
Vintage racing - old guys on old bikes
