My son has a 07 Streetbob with a 96ci motor with only 1600 miles. The rear cylinder cuts out after about 30-50 miles depending how hot it is outside. 3 harley mechanics have not figured out the problem yet. The plugs, wires, coil, and crank position sensor, fuel line from tank, and rear o2 sensor have all been replace by these mechanics and still having problem. The latest time i was able to get a code reader on it while is was misfiring showing 4 error codes...3 for rear o2 sensor and 4th for overheating. Still no fix after o2 sensor. Bike has 2" tank lift and drag bars with internal wiring. I've seen others on this forum with similiar problems. Any help?