I have recently bought a XT 550 and would like to know if someone can help me. The cycle has a flat spot at about 100 km/p in 5th gear. What can be the couse as I have cleaned the carbs [inside & out]. There were rust in the tank but it is removed and cleaned. I put feul system cleaner in the system but the problem still persists. And I will appreciate it if someone can e-mail me a copy of the Owners manual.