I would like to know the top speed with stock gearing as well. I often thought of making one street legal, especially now that the new four strokes need such often maintenance. I´d rather have the simple ole XR than the complicated and timely new stuff. But with only 5 gears I always thought it would be slower than, top speed wise, my 1987 XT350. Which went 95mph. Maybe a used tt350 is better than an xr400? I´d expect the suspension to be better on the xr though not sure.