As for hallucinogens, a lot of people thankfully are aware that you mustn't drive while hallucinating for obvious reasons. But LSD only causes hallucinations above a certain point, a common tripping dose is 100 micrograms (also called ug). A trend these days is to take sub tripping doses for relaxation purposes among other purposes. I don't think that this is especially useful unless you can be absolutely certain of how pure and concentrated the drug you get is, but because this causes no visual effects, the question is whether you can drive (or cycle or walk well) on it? I am not certain about this given that people react differently to different drugs, heck even 600 mg of caffeine in the morning (yeah, that was not a good day for a lot of coca cola) one day didn't affect me at all when others would react very differently, but given that LSD is also a bit of a depressant and anxiolytic, I suggest caution. There is always a principle in law that says that if you are unsafe to drive, even if you are below the normal legal limit as defined by blood alcohol content or THC per millilitre of blood content or whatever, then you can still be charged with a DUI. Given how it's impossible to truly know by looking at it how much LSD is in a tab or juice or whatever and how different people respond differently, the best test is a field sobriety test in my opinion. Can you recite prime numbers backwards from 100, can you stand on one leg effectively, do you follow another person's eyes, etc.
Stimulants are similar. They don't have any properties I'm aware of that will automatically entail impairment like being unable to see, but they can for some people and especially the higher the dose, cause anger and aggression, jitteriness and being unable to sit still. Again, field sobriety is probably your best bet, especially knowing how impure cocaine and methamphetamine often are (this doesn't apply for adderall or caffeine, but they have the same aggression, jitteriness, etc properties). This also goes for 3,4 metheylenedioxy N methamphetamine, molly/ecstasy, although given that it's often cut with other drugs, apply the same reasoning to other stimulants. Jitteriness, inability to sit still, especially in higher doses, and overdoses are concerns that you should keep in mind when getting home. And I also should point out that a lot of people who use cocaine are also drunk at the same time, (and this also happens to go for caffeine as well). Stimulants do NOT counter the effects of drunkeness on your ability to drive. In fact, cocaine and alcohol combined form cocaethylene, which impairs you even more. Not a good combination with a steering wheel in your hand, even a bicycle handlebar is not something you should do either.