Dear Savvy Senior: What can you tell me about electric bicycles? A friend of mine, who’s almost 70, recently got one and absolutely loves it. He told me he rides more now than he ever did his regular bicycle. — Interested Boomer

Dear Interested: Electric bikes have become popular among U.S. baby boomers over the past few years because they’re super fun to ride and easier on an aging body.

Electric bikes, also known as e-bikes, are conventional bicycles with a battery- powered “pedal” or “throttle” assist. When you saddle up and push the pedals or throttle, a small motor engages and gives you a boost so you can whiz up hills, ride into head winds and cruise over challenging terrain without gassing yourself or taxing your knee joints.

Many older e-bike owners say that they ride more frequently and go farther and longer than they ever would with a traditional bike. Here’s what you should know about e-bikes, along with some tips to help you choose one.

What to know

E-bikes are more complicated and expensive than regular bicycles, so you need to do some research before you purchase one. For starters, you need to know that there are three types of e-bikes to choose from:

>> Class 1: “Pedal-assist” electric bikes that provide assistance only when the rider is pedaling, and only up to 20 mph. These are the most common type of electric bikes.

>> Class 2: “Throttle- assist” e-bikes that let you use the electric motor without pedaling, like a motorcycle or scooter, but only up to 20 mph.

>> Class 3: “Speed pedal-assist” e-bikes, similar to Class 1, except that the motor will assist with bike speeds of up to 28 mph.

Because they’re electrically powered, states and local communities have varying regulations regarding the use of e-bikes. In many states, Class 1 and 2 e-bikes are allowed to be ridden wherever a traditional bike goes, while Class 3 is generally allowed on the street due to its higher top speed. For more information on your state’s e-bike laws, visit PeopleForBikes.org/ e-bikes.

You should also know that e-bikes come in many different styles — commuter, cruiser, mountain, road, folding, etc. — just like traditional bikes to meet different riding needs. They also run on rechargeable lithium-ion batteries, and their motors are either hub-driven mounted on the front or rear wheel, or mid-drive motors that are mounted to the frame at the bottom bracket between the cranks.

The only downsides of e-bikes are weight and cost. Because of the battery and motor, e-bikes are much heavier — 50-plus pounds — than traditional bicycles, so it can be more challenging if you have to manually lift or maneuver your bike a lot. And e-bikes are expensive, typically ranging between $2,500 and $3,500.

E-bikes are made by many of the same established companies that make traditional bikes, like Specialized, Electra, Schwinn, Trek, Giant, Cannondale and Felt, along with a number of upstarts like Juiced Faraday, Pedego, Elby and Hi Bike. To shop for an e-bike, find some good bike shops in your area that sell them so you can test-ride a few.

If you’re interested in a cheaper option, there are also e-bike kits you can purchase at places like Walmart, Amazon.com and eBikeKit.com that can convert your regular bike into an e-bike for a few hundred dollars.

Jim Miller is a contributor to NBC-TV’s “Today” program and author of “The Savvy Senior.” Send your questions to Savvy Senior, P.O. Box 5443, Norman, OK 73070; or visit savvysenior.org.