Horizons Unlimited - The HUBB - Suzuki TS185 Performance Tuning/Race Advice?

I know this isn't really amazing adventure advice, but there seems to be a lot of TS185 knowledge on this forum.

While I am not currently planning an around the world adventure at the moment, I would like to do one one day, probably when I'm a bit older and have paid off the house, and my kids have left home (I'll have to have some kids first though!)

What I do have however is a mighty Suzuki TS185, it's a 1978 model according the frame number but some parts of it appear a bit later model, like the coffin tank and box section swingarm. It has plastic guards too. It has the later model exhaust, I havn't pulled the engine apart to see if it has the crankcase reed induction as well as the piston port, but it is very torquey down low so I'd imagine it does. It appears to have the earlier forks however being 30mm but it has the later model conical hub front drum. So it appears to be a mixture of ER and earlier, well pretty much all ER except from the forks?

I'm planning on doing a bit of trail riding and Vintage Motor Cross (VMX) on this fine steed and was wondering if anyone had any advice on getting a bit more performance out of it, both from the engine and the frame/suspension.

I live in Christchurch, New Zealand.

I was going to build an expansion chamber for it as the factory one doesn't appear to be very high performance, it just appears to be that shape because it was convenient to fit nicely in between the riders leg, frame and engine.

I can get some XR200 forks for it cheap, maybe they would be a bit better being longer and softer with more dampening probably.

For the back end I was thinking of doing a monoshock conversion using the simple setup of some triangulation on the swingarm and the shock mounted to that then going straight to the frame, although it might be difficult to get it rising rate, not falling rate and still having enough room for some kind of airbox. Plus I'd be adding weight too which isn't really a good thing. Other issue is that it may not be eligable for VMX anymore.

The other option which probably would be more approeate to the period of the bike would be some long twin shocks mounted on a steep angle. This would be simpler and be more period, definatly be eligable for VMX and be a lot easier to do. Probably more reliable too with less frame cracking.

I just have one of those foam UNI-FILTER pod filters on it for an aircleaner at the moment as the old airbox rubber was too stiff and hard to get over the carb inlet and the airbox was all busted up. I'll just make a new airbox to go around the pod filter somehow so I can do river crossings which I have a strange attraction to. Last time I went out I dropped my bike fully underwater a couple of times but it didn't mind at all. Took a little bit to get going but it was happy as larry after all the water sitting in the crankcase and exhaust blasted out the muffler when it started.

Any advice on this matter would be great,

Cheers,

Sam