If anybody wants to check things out "from the source" here's where to start:
Forest Service Statement on Electric Bicycle Use:
www.fs.usda.gov
Note that the document referenced here in "7700 Travel Management - Zero Code" is NOT a rule-making document. It provides DEFINITIONS. But you need to start there because when you read rules, those definitions are what they're talking about. It specifically defines e-bikes as follows:
and a "Class 1 E-Bike" is absolutely not the same as a "bicycle":
Then in "7710 Travel Management – Travel Planning" they add a few more details. For instance, they are introducing a new classification "Trails Open to E-Bikes Only". I don't know of any such trails yet, but they're opening the option.
If you read 7710 you also won't be satisfied when it comes to answers. That's because actual trail designations and rule-making about their use is left to the managers of the parcels they're in.
There is no nationwide standard that applies to all USFS (or BLM) land. A lot of folks want to try to go to some single document and say "a-ha, I can do it on USFS land" but that's just not how it works. With some regional nuances, it's generally safe to assume you CANNOT do something unless it is specifically LISTED.
That's why older trail and road makers so often list a bunch of things you can do, but not the things you can't. The newer ones I run into often list both DO and DON'T but many older signs just list DO. If it's not on there, it's a DON'T.
E-bikes are not allowed anywhere except on roads/trailed that allow MOTORIZED VEHICLES. It doesn't matter what Class they are. 1/2/3 - all are a "no". Period.
I get the whole "I'll take my ticket" argument but it doesn't hold water IMO. You can say that about anything. You can do 90 on the highway and cut people off left and right and just say "I can afford the ticket." It doesn't mean you should be proud to post about it online.