The Waldo Lake ride is another Oregon classic that is well worth the drive if you have the time. It is one of the longer rides to get to from Bend and is actually closer to Oakridge if you are going to be doing some riding in that area. The lake itself is one of the largest natural lakes in the state and the second deepest. According to a forest service web site, " ...Waldo is one of the most dilute large lakes in the world. The water chemistry of the lake has been compared to distilled water." There are no speed boats allowed on the lake to keep it pure and clear. If you are making a day of it, and have some type of paddle craft, bringing it would be highly recommended. The whole west side of the lake is wilderness except for the lake shore so mountain biking is legal. The only downside to this area is that for much of the year from Cultus Lake south the mosquitoes can be intense. If all you are doing is biking, it is tolerable if you keep riding. If you stand out on some of the points in a breeze you can take a break without making donations. Like many mountain areas later in the year, when things dry up a bit the mosquitos aren't so bad. Still, if you are mosquitophobic you probably would want to do other rides in the Central Oregon area first.
At 22 miles, the ride is a fairly long loop for most riders. The southwestern shore is the most difficult but like most Central Oregon rides will involve only a couple of short walks if you are unable or unwilling to do the technical sections. The forest around the lake is very nice except for the northern end which was burned in a wildfire, and can now get a bit dusty plus will be likely to have a few downed trees across it. There are occasional hikers on the trail so, as always, slow down or stop for them. For riders that are reluctant to commit to the whole trail, the ride on the eastern side of the lake between the boat ramps is technically easy and fun. Along that line, and not to be overlooked is the ride to Bobby Lake to the east which is like a hard pack dirt sidewalk and can be ridden at amazing speeds.
Clockwise or ounter-clockwise? Both are popular, but IMHO clockwise from the southern boat ramp is the best. That way you ride the more difficult section on the southwest side while your still fresh, and the high unnamed rocky point on the northwest corner is the best lunch/break spot. You will be ready for a break by the time you get there. (43.754481, -122.051239 approximately) If you are doing it clockwise be sure not to take the shoreline trail past the Islet campground as it totally dead ends at a beach after about a mile. The main trail is away from the lake far enough on the east side that you seldom see it. One advantage to doing it counter-clockwise is to ride through the burned section without shade early in the cool of the day, but Waldo is not a real hot place usually and you could always jump in the lake to cool off.
If you have some folks in your group who prefer mountain biking that involves as little peddling as possible, they have lift assisted riding close by at Willamette Pass Ski Area.
All of Waldo is in National Forest so you will need a pass.
Getting to the lake warrants some extra description. If you are coming from Bend and looking at a forest service map it is real tempting to take dirt road 4290 instead of going over Willamette Pass and doubling back on 5897 to Waldo (all paved). 4290 is usually super washboardy the whole way. The Forest Service and Fish and Game don't really want a lot of people using it because it is a wildlife corridor and so they purposely don't maintain it much. No matter where you drive or what speed it doesn’t matter. You could drive a few miles on it to see if you are lucky enough to be there when it was recently bladed. Also if they kept it in real good shape people from “the valley” would use it as a short cut to the other high cascade lakes which the forest service also doesn't want. If you Google the destinations below from a Bend location it will have you driving on 4290. The distance from the center of Bend to the parking area at the north end of the lake via 4290 is 60.2 miles. From center of Bend to the southern parking area via Willamette Pass is 81.6 miles. Road 4290 is only about 12 miles long but you will not be going a hole lot faster than 25 miles an hour. It is a tough call. The time is about the same but the wear and tear on the vehicle is lot more via 4290. If 4290 happens to be in good shape then that is the way to go.Waldo Lake Trail in Google Earth