Fork oil do I need in each on a fatboy

To replace the front fork oil first support the motorcycle so the front end is off the floor and the forks are fully extended. Remember that the FLSTC and FLSTF models have a preloaded fork spring and that the fork tube plug is under spring pressure.Then you remove the fork tube caps. And then you drain the fork oil. ON FXSTD models, your remove the drain screws and washers from each fork and drain the fork oil this way. ON ALL MODELS EXCEPT the FXSTD, remove and discard the drain screws and washers from each fork and drain the fork oil and then you install new drain screws and washers. ON FXSTD models, apply LOCTITE THREADLOCKER 243 (blue) to the drain screws and tighten them to 12-18 inlbs (1.4-2.0 Nm). ON ALL MODELS EXCEPT FXSTD, tighten the drain screws to 52-78 in-lbs (5.9-8.9 Nm).THEN fill the fork with Harley-Davidson TYPE E FORK OIL (Part No. HD-99884-80).Either by installing oz or cc's of fluid if the forks were left in the frame or by measuring the amount of oil in the tubes in inches or mm if the forks were removed from the frame and disassembled. In the latter case the oil level is measured from the top of the fork tube with the spring removed and the fork fully compressed.

MODELs FLSTC, FLSTN use 13.4 OZ 395 cc4.41 inches 112.0 mm
MODEL FLSTF uses 13.4 OZ 397 cc5.04 inches128.0 mm
MODELs FXST, FXSTB, FXSTC use 12.5 OZ370 cc 6.69 inches170.0 mm
MODEL FXSTD uses 11.6 OZ343 cc 7.48 inches190.0 mm

FINALLY tighten the fork tube caps to 40-60 ft-lbs (54.2-81.3 Nm).

2003 Softail Type E Fork Oil Amounts
MODEL OZ CC IN. MM
FLSTF, FLSTC 12.9 382 4.72 119.9
FXSTC, FXST,
FXSTB 12.0 356 7.28 184.9
FXSTD 11.6 343 7.48 189.9

I have an '04 Fatboy and work in a dealership. Swapping the oil tank is not fun! There is very little clearance for tools and your hands! If you decide to try it yourself, get a service manual. It will make the job a little easier, with the steps you need to take to remove the tank. Or, get a service manual and read how to do it and decide if you want to tackle this job yourself.

When was the last time the fork oil was changed? Has there been any leaks? Loss of oil will cause the forks to go soft.

If you ask this question YOU should not be doing it! but your *** on the seat not mine.
Remove ...........front wheel, front fender,top fork cap and loosen lower triple clamp bolts under head light cover, forks are now out!
Remove 6mm bolt at the bottom of the fork leg and drain oil,remove dust seal and wire clip, now remove the upper fork nut (the spring will jump out at you).Pull the leg and tube away from each other, the old seal will stay on the tube..clean and reassemble driving NEW seal down into place with wire clip.....refill with oil

Specs should be in owners manual.If not stated in oz.A good dealer will give you this info for free. Check the web for the conversion to oz from cc or other measure.

change the oil seals and oil in the fork,and avoid wheelies on the bike and off road biking