DIRECTIONS: You can do this loop starting from either the bottom of the Ramona Trail or at the start of the Thomas Mountain Truck Trail. It depends on if you want to do the 2.8 mile road part of the loop at the beginning or end of the ride.
Start of Thomas Mountain Truck Trail from Ramona Trailhead: From Ramona Trailhead parking lot, turn right and take HWY-74 1.5 miles to Pyramid Peak Road. Hang a right here and go .4 miles to another T-junction at Hop Patch Springs road. Turn left miles and follow the road .8 miles where you will see a dirt pullout on your left just aa the road turns to dirt. Park Here. Get directions from your current location to this spot.
RIDE NOTES: These notes are for starting at the beginning of Thomas Mountain Truck Trail. Add to 2.8 miles to the mileage I mention if you start from Ramona Trailhead.
The next section of mountain road started out as chaparral and slowly gave way to sparse pine trees as we climbed up to Toolbox Springs Campground at 6,150 feet at mile 5.5. This is the "traditional" start of the Ramona trail. We did something different that added some more singletrack. We picked up the Ramona trail off to the right of the restrooms. (The picture to the left was taken from the trail). We then rode down the trail for maybe 100 yards and then hung a left onto another single track. I am unsure what the trail name is, but it is labeled with a USFS trail marker that does show it is open to Mountain Bikes.
We followed this rolling singletrack (more rolling up than down) until at mile 6.15 it crossed a fireroad that connects some primitive campsites to Thomass Mountain Road. We did not continue on the singletrack at this point. Instead we hung and left on the fireroad and went uphill. We rejoined Thomas Mountain road at mile 6.5 and continued uphill (to the right). This section of singletrack is a nice break from the climbing, but you may just want to continue on Thomas Mountain Road instead of taking this side trip as you will go down this singletrack latter in the ride. (My GPX route, reflects staying on the road)
From this point the climbing became a little more intensive and the pine trees became larger and views just kept getting better. We also starting noticing the remnants of snow in the shade which is always nice to see in SoCal. At 8.3 miles we peaked out at 6,667 feet near the peak of Thomas Mountain. There is a trail off to the left that takes you up to the peak at 6,825 feet (we did not take it). From here Thomas Mountain Road turns downhill, but we only went a short ways (at little over .1 mile) to the first sharp turn (left) where we picked up a single track. There is a trail marker right in the middle of the turn so it is somewhat hard to miss. The trail does not have a signed name or forest service trail number. For lack of anything else I will refer to it as Upper Ramona Trail.(Update: As of May 2021, the trail marker does not reflect a name or number but the update forest service maps show it to be "Thomas Mountain Bike Trail", number 3E37.)
If I had to describe this upper trail in one word it would be CHANGE. Up near the top the trail is somewhat soft as you weave through pine trees on mostly buff trails. However there are small technical sections that pop here and there that can trip you up if you do not pay attention. There are also a few roots to contend with as well that could get you an unscheduled dismount if you start zoning out. The top of the singletrack started out rolling through a wide open meadow that cut through sparsely spaced pines that provided a very alpine feeling to the experience. The trail did have a few tight places and transited through dense brush along the hillside at times.
After 2 miles or so of fun singletrack riding we crossed campsite fire road at mile 10.75 where we came out on before. This time we went straight across the fireroad and enjoyed this section of the trails going the other direction. We soon were back to where we had originally peeled off from the traditional Ramona trail. We hung a left here and the trail started to get a little more technical with rocks and roots as well as some tight switchbacks. The trail made you stay on our toes as sections of rocks would often pop up around corners they required you to stay fully engaged mentally. This added a really cool feel to the trail.
For many of the rock sections the adage "Speed is your Friend" is quite true because many of these rocks could get you an express pass to Endo City if you hit them going too slow. The further down the trail we went the more technical the trail got as it transitioned from pines to chaparral. The lower portions of the trail were quite reminiscent of Noble Canyon with lots of small rock drops and loose sections. As of 2021, this trail is a lot less like Noble Canyon and the speed is your friend thing is less of a concern.