Most of the big names are very reliable. I've had honda, Kawasaki, Suzuki, polaris. With regular maintenance I haven't had any issues with any of them other than one Polaris.
One Polaris I had to rebuild the carbs. I attribute that to the original owner only putting 50 miles on it in seven years.
for dirt and street bikes you can add Harley, BMW, ktm and Yamaha to that list.
The BMW had some costly maintenance, but still very reliable. The only ones that really gave me any issues was an early 60s Harley. But I knew going into that project that it would cause some headaches and that was part of the fun.
I think any of the name brand machines out right now will be good if you take care of them.
-Jake