Footer wrote: I can ride at anytime. Don't want to go too early but can also go anywhere as long as I can figure out the transportation part.
If you're at the Mid-Levels, then the nearest decent trails will be
Project X at Lamma Island
... just get yourself (ride) to the Central Ferry pier and hop on the Lamma Island ferry.
Otherwise, it'll be the massive Tai Lam network, and there are a few entrance points, depending what skill level you're at... and changes which would be the best way to get on to the trails. However in general, you can take the Tung Chung line MTR from Hong Kong Station and change for the West Rail line at Nam Cheong.
If you want to ride the easiest Tai Lam Reservoir loop, get off at Tsuen Wan West and ride (or take taxi) to Sui Lam open prison (past Tai Lam Cheung Tsuen):
goo.gl/maps/7bjVY
... do the trail in a clock-wise direction. It's a bit hike-a-bike at first, however once on to the flat stuff, the trail flows nicely. You can ride it in reverse to go back out... or head on the (boring) concrete road on the other wise of the reservoir back to Sui Lam.
From Tsuen Wan West, you can also get up to the top of Route Twisk (Tsuen-Kam Gung Lo) for the Ho Pui DH trail... that's a "bit" rough and extreme though, with some nasty stream crossings:
goo.gl/maps/PGBsq
One stop further to Kam Sheung Road station, you can ride into Ho Pui village (this bit is flat road!):
goo.gl/maps/u2nT6
And one in the village go up to Ho Pui Reservoir where you can do the reservoir loop clockwise or ride along Ho Pui Pass that takes you into the far side of Tai Lam Reservoir:
hkmba.org/index.php/trail/tai-mo-shan/ho-pui-reservoir
I will be out riding Sunday, however have a female friend in tow... so would be rather ploddy and slow. Any others in for the ride might get a bit bored.

Will start around 1~2pm from Ho Pui village, up to the reservoir, along Ho Pui pass then an out-and-back run of Tai Lam Reservoir trail:
www.mapmyfitness.com/workout/218293762