A "gold" rated u-lock weighs four to five pounds. A "silver" rated u-lock weighs two to three pounds.

For touring, I'd suggest a light weight "silver" rated u-lock around the rear wheel and a "bronze" rated cable around the front wheel. The OnGuard Bulldog is a very good lightweight u-lock.

Sometimes folks who are touring can't find a bike rack or slim pole to lock to, and are forced to use a large tree or telephone pole. A six foot long cable is easy for a crook to cut, but a long cable is useful in locations where a u-lock will not work.

If your bike is locked to a tree with a cable lock, you still need a u-lock attaching the rear wheel to the frame. That way, a crook can't cut the cable and just ride off on your bike.

"Gold", "Silver" and "Bronze" rated locks are listed at:

www.soldsecure.com/Leisure.htm