The "Thrilla in Woodinvilla" route uses Puget Powerline, Redmond Watershed, and Tolt Pipeline trails.
The Puget Power Trail is gravel surfaced. Redmond Watershed can get a little muddy but it holds up well during wet weather. The Watershed is also a multi-use trail (bike, hike, horse, and the occasion senior once the trail instersects with the Trilogy trail system.) Tolt Pipeline is dirt doubletrack. Some of the dirt connector sections can get fairly muddy. Overall, the Thrilla route is a good dirt ride for wet weather conditions and is extremely well maintained throughout the year.
This is also the same route used for the Stinky Spoke that usually happens mid-January (yes, they purposely try to pick the worst day of the year for this event). While historically, the Stinky Spoke ride was counter clockwise (same as noted in the GPS map, in recent years they have reversed it and now it runs clockwise - kicking off with a killing of a climb 5 minutes in called Heart Attach Hill that takes you up the Tolt Pipeline Trail
From Redhook, ride back to the pedestrian bridge over the river and head south along the paved Sammamish River Trail
(an extension of the Burke Gilman Trail) towards Redmond. About 3.5 miles from Redhook, look for the high overhead power lines. The Puget Power Trail (PPT) begins under the power lines, just before some apartment buildings. Turn left onto the PPT and climb up to the crossing of Redmond-Woodinville Road. Cross the road and continue climbing. After cresting the hill, the wide gravel PPT crosses several roads.
After a couple more descents and climbs, the trail descends down to Avondale Road. Use the pedestrian signal and cross to the other side. Parallel a wood fence and then cross over a creek on a bridge. Careful, the dirt road is a driveway so keep an eye out for vehicles. Immediately after crossing the creek, see a sign for the PPT and turn left. Wind through the woods on the wide dirt trail, stay straight at a 4-way trail intersection and take lefts at the next two intersections. The PPT climbs a short hill under the overhead power lines before it comes out on a paved road. Take a left at the road (196th Ave) until it tees into 116th St. Turn right and climb up to a stop sign at Redmond Road. Continue straight at the stop sign and take the next right onto 206th Ave. The road descends and then turns left under the power lines. Take the bark trail straight ahead up "Horse Pasture Hill" and climb towards a fence.
On the right side of the fence, find a trail that parallels the fence. Climb up and at the sign for the Redmond Watershed vear right onto an established trail. The trail comes back under the power lines where you take a right. Follow under the power lines and after crossing a 4-way intersection look for a short section of trail on the right. The trail crosses under the power lines again and then descends to a bridged creek crossing before climbing again. At the top, take the left trail (the other two lead back towards Novelty Hill Road).
Stay on the main trail through the Watershed. Each intersection is signed. After several climbs and descents, you'll come back out on a level section of trail before diving back into the woods. Enjoy the descent (keeping an eye out for oncoming trail users). Pass by the first trail intersection (hiker only) and take the second intersection to the right on the Collins Creek Trail.
The trail winds back and forth before coming to a soft T intersection where you stay left (right is hiker only). Stay straight across two street crossings (the second is traffic signal controlled). Wind back and forth until you come out in a development. Stay to the left of the stormwater pond and come out on a paved road. Veer right across the road and go through the wood bollards onto a gravel trail. Left at the first intersection and then left again along another stormwater pond.
The trail will cross a couple wood bridges and then climb sharply to the right. At the top, stay left and follow the trail behind the houses. After climbing a bit, you'll come out onto the Tolt Pipeline where you'll take a left.
The Tolt Pipeline will stay essentially straight for the next 5 miles. A few descents and then one longish climb. Two more steep descents and after crossing another pedestrian bridge, climb to the top onto a dirt road. Stay straight and descend steeply down through the gate. Pay attention and watch your speed down the hill. If you are experienced (or want to be) with the final steep hill: [the fastest way without having to cross over the rivulets is on the left side right after the gate. Try it out first in daylight when it's not too sloppy, and watch out for the 2 or so sections where the stream bed slightly cuts into the path from your right. After crossing Hwy 202 (be very careful) go through the gate again and stay straight towards the Sammamish River. Once you intersect the paved Sammamish River Trail
, turn left and complete the loop to Redhook.