It's no surprise that sales of bicycles built for two are booming. Tandem bicycles elevate heart rates as well as conversation and provide a fun workout for partners of varying abilities. They are expensive, however. One of my buddies puts the cost in perspective, however, noting that they are much cheaper than a divorce attorney. Here are four good bikes in different price ranges.

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Family-friendly ride

Raleigh Companion: A versatile entry-level bike for the family.

Likes: A bargain that will suit most people's needs. Deep-cushioned spring seats and rear-suspension seat post absorb bumps. Comfy riser handlebars keep the front rider (or "captain") from bending too much. Suitable for short or tall rear rider (or "stoker"); my 8-year-old son, Joey, just fit. Handles hard fire road mountain biking (with knobby tires) and fast pavement riding (with skinny slicks). Includes 24-speed drivetrain, quick-release wheels (for easy removal) and a quality brand name.

Dislikes: Too slow for hard-core riders because of small mountain-bike wheels and wide tires.

Price: $599; (800) 222-5527 or (253) 395-1100; http://www.raleighusa.com .

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Break it down easily

Bike Friday Family Tandem Tour 16: Toddler-friendly fold-up tandem.

Likes: Easiest tandem to ride with kids and take on trips. Stoker seat fits 3-foot toddlers and 6-foot-2 adults. Bike disassembles into two sections in 10 to 15 minutes, fits easily in car trunk. Front and rear rack mounts for panniers (others have rear only). Clever built-in wrench/pedal tool fits all bolts.

Dislikes: Some shops don't carry tires and inner tubes for 18-inch diameter wheels; must carry spares. Little wheels are fast but less stable than standard road or mountain bikes.

Price: $1,195 (16-speed); (800) 777-0258; http://www.bikefriday.com .

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27 speeds in steel

Burley Rumba: Steel-framed performance roadster.

Likes: Very fast and solid. A 27-speed drivetrain with brake-lever shifting. Price is on the low side for a road tandem.

Dislikes: No front rack mounts, so frame can hold only rear panniers. No suspension seat post for the stoker.

Price: $1,799; (866) 248-5635; www. burley.com.

Off-road enthusiasm

Santana Extreme: High-end mountain bike tandem.

Likes: A great choice for off-road adventures. Safe, powerful disk brakes. Massive bump-eating suspension fork. Rear suspension seat post. Symmetrical rear wheel (exclusive to Santana) is extra durable. Ultralight for a suspension bike at 35 pounds, 10 ounces.

Dislikes: Extreme price. You'll need to be very trusting to ride in the rear on steep trails.

Price: $6,000; (800) 334-6136;

http://www.santanainc.com .

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— Roy M. Wallack