If you choose to undertake fixes to your Honda TRX90X then it is usually a good idea to possess a Workshop Manual to keep just for a reference in the event you need to know ways to take off a particular component for example Drive Shaft and install it again accurately.
Honda TRX90X Workshop Manuals offers clear targeted diagnostic wisdom for your vehicle so if something is broken it can help you ascertain what the issue is and how to correct it. After that you can assess if this can be achieved yourself or if the job is too big you can actually book your TRX90X into a trusted mechanic.
Honda TRX90X manual