Originally Posted by
EBikeFL
If you purchased the bike new then I'd go to the bike manufacture's website and check the max size tire you can use front and back. Remember, if you have fenders for the original tires they may not work/cover the larger width tire.
If you are reaching 30+ mph you should also upgrade your brake rotors to 180 mm or more. Hydraulic brakes are a must at 30+ mph as well.
The manufacturer did not list any specs for the bike until I asked them to a week ago. They didn't mention the widest possible tire, though. The brakes are V brakes, so there's nothing to replace.