love your KDX & funny thing is, have my HT1 running now [yesterday], actually went out the gate & straight into a wheely exactly as i racalled from back in the day then wife came out doing a war dance [no helmet & i'm a walking head injury--sorry dear], old habits hard to break!! I'll put pics up showing [little] difference after waterblast & lots of hours freeing up etc. Anyway, runs absolutely perfect with no motor noise whatsoever. Usual piston port growl & pulled an easy 50mph up the road. BUT, KDX link is my farmer neighbor dropped of a KDX pipe [cleaning out the shed] & i cut the first bit off to get the bend for the HT1, then a bit of RD350 header then [being too stingy to fill my gas plant] i quite successfully arc welded it all up [barely leaks at all], might go over it again if i can get rid of the flux & zig zag over the top. Wired the lights to the 25/25 high beam, dip switch stuffed, hooked the stop light fillament to soak up some voltage & did a night run down road--really good. Have a 6volt ac regulator which i might fit [bulb saver regulator]. Anyway--all that story was about the KDX link via exhaust. Cheers.