I have been mountain biking for 30 years now starting off on a full ridgid trek chromoly 850 and working up from there. I had to take 15 yrs off due to medical problems(EDS if ya know what that is) but after finally figuring out what was causing the problems I started to get back on my bike. I originally did it just to help me sleep better and was so happy to see it worked and I am now sleeping better. I never planned on getting into good enough shape to go offroad again but eventually I was doing over 10 miles and decided to try a short trail. 2 miles into it I was overheated, out of air and still wanted to do more as I just love it. I have been trying to build my stamina but then someone put a bug in my ear about the ebikes and said they can make you feel 30 again(49 this month). Needless to say that stuck there until one day I stopped at the bike shop and made the mistake of jokingly asking about financing and they said they did one year free financing. So 2 days ago I picked up this trek rail 9.8 xt gen 4 and I am trying to get use to it but it is a long way from that 850 I started on years ago. What things should I be looking out for or listening for? Are there any upgrades that I should just do now or wait till???? Thanks in advance