The person in the US that knows how to set up a DTX bike is Phil Darcy in Fort Worth, TX. He has built and currently builds the top flat track bikes in the country. From motors to suspension set-up. Darcy Racing 2524 Weaver st suite #106 Ft. Worth TX 76117 (817) 834-7223 (also FAX)
Then you'll need a steel shoe. Ken Maely 8580 Bedford Motorway Corona, CA 91719 (909) 277-8989 (909)277-0410 FAX
I don't know if anyone took over Kens' work, bur I got my shoe from: Hot Shoes by George 504 Lewis Ave. Norwalk, Iowa 50211 515-981-9478 A steel shoe makes a BIG difference!
The most fun I've had flat tracking was in the back of the Kawi shop. SL70 { it was in 74 } , 2nd gear, wfo, and control the bike by leaning backward or forward and right or left. Nearly full lock sideways lap after lap. Sometimes the back tire would hook up, rocket the bike down the straight and you would pitch it into the next turn to slow down and make the turn. Sometimes you would pitch the bike right out from under yourself and slide until you hit a workbench. Then your bruised butt would let someone else ride. This was on a polished concrete surface that had been sealed mutiple times. Perfect traction in that the front tire would bite and the back could be made to slide with aggressive riding. Some good dirt riders never could get the hang of sliding. It's like balance wheelies, some can and some can't. The two best at wheelies were also the best sliders Flat track bikes need different geometry because of countersteering. As long as the tires are hooked up then the geometry is what ever is built into the frame. Once the back tire is hung out then the ACTUAL rake and trail would be measured between the appropriate points on the frontend and the ground. The more the back is hung out and the more the bike is leaned over then the more rake and trail there is. This is why flat track specific frames have steep fork angles and little trail when measured straight up. This is also why a lot of them head shake going down the straight but handle great when sliding.