100-120mm will work great, depending on what you want the bike to do. 100mm forks will give the bike quick handling, and classic 71/73 degree angles. 120mm forks will make the bike more stable at speed and are better for slightly more aggressive riders. 120mm is the largest you can use and not void your warranty. If you really want to use a 130mm or longer fork, you should be on a Blur LT or Heckler.
Extra small and small Julianas use a 6.5” x 1.5” (165x38mm)
For medium size frames: 7.875”x 2” (200x50mm)
The shock mounting hardware for all frame sizes is 22mm wide with an 8mm through hole.
1 1/8"
The Juliana uses a 30.9mm seatpost. Make sure it is always inserted a minimum of 4” (100mm)
34.9mm (supplied with frame)
A shimano 34.9 top swing/ top pull. Anything but saint should do the job.
The Juliana uses a 68mm bottom bracket shell, and a 50mm chainline. Pretty much any of the newer external bottom bracket cranks will mount up without issue. The Truvativ stylo and shimano Deore XT are our favorites. If you are using an ISIS setup, you need a 68x113mm bottom bracket.
Most 2.3.” tires will fit in there, but that is about the max.
140-160mm.