APRILIA PEGASO STRADA 650 MOTOR PROBLEMS

Hello guys, I have been fighting with a pegasus for several days, first in the 1st, 2nd and 3rd speeds at low revolutions I was pulling and stopped, I checked all the sensors and were correctly according to the workshop manual that I found, the diagnosis that the vehicle has no error, the battery was low Start, has someone like this happened to him?

Greetings, if someone had the workshop manual in Spanish I would appreciate it very much, I have found it in a very rare language