Bear in mind that if the helmet did its job most people would tell you that they did not even hit their head, or did not hit their head that hard. And the thin shells on most helmets now tend to hide any dents in the foam. But if you can see marks on the shell or measure any foam crush at all, replace the helmet.

If the bike was in decent shape when put away, and has not been exposed to the weather, there's probably very little that needs to be done. The tires would be the biggie -- likely they're checked and may need replacement (though not for certain). Inflate them to listed pressure and check the sidewalls for cracks or bulges. Assuming rim brakes, the brake pads may very well be hard and in need of replacing. But you can't tell for sure until you try. Otherwise, wipe off the dust, inspect for rust, and put a bit of oil on the chain. Check that the wheels spin freely, with no play in the bearings, and that the steering tube likewise moves freely with no play.

When riding, always:

• Go With the Traffic Flow. Ride on the right in the same direction as other vehicles. ...
• Obey All Traffic Laws. A bicycle is a vehicle and you're a driver. ...
• Yield to Traffic When Appropriate. ...
• Be Predictable. ...
• Stay Alert at All Times. ...
• Look Before Turning. ...
• Watch for Parked Cars.