Ok now I have got the handlebars sorted I need to change tyres. It still has the original 22 balloon tyres on the back and 23.5 on the front. Knobblys are nearly totally worn down and lots of surface cracks. Do I replace with original size and look or go for smaller 20's on the back. I will mainly be riding on dusty hard bush track with occasional medium soft sand. Some flat limestone areas on the track as well. I was thinking some sort of all terrain tyre. Any suggestions and combos greatly appreciated. My rims are a bit bashed about on the edges so will probably change them as well. Thanks again in advance . Cheers , Rob