First off you don't have to bled all of the screws, the caliper is universal in nature, that is it can be used on either side and that is why it has two bleeder screws. You want to bleed the air from the highest screw.
When replacing a master cyl. you will want to bleed that first before doing the whole system. Either bleed right at the screw where the brake hose bolts to the cyl or go down stream to the first connection. I usually just bleed the cyl at the top banjo bolt and go from there.
A neat trick is to tap the cyl with the back side of a screw driver or a soft mallet to help dislodge any air bubbles the are caught in the piston cavity. If you do this with the cover off and with the "fluid tank" about half full you can see the bubbles coming out, also try working the brake handle back and forth to held get all of the air out, this can take a little time.
Next I like to do the next closest caliper and then the one that is farthest away.
To get the fluid started, try letting gravity help, pull the top off of the master cyl. and crack both caliper bleed bolts and let the fluid drain thru the system, just make sure the master cyl does not run dry! Once you have a good clean flow of fluid from both calipers you can go on to the pressure bleeding part, just like a car, pump up the system, hold pressure, crack open the bleeder screw to expel air bubbles, while holding the brake "peddle" down tighten the bleeder screw again, pump up the system again and repeat until no air comes out and the fluid is clean!
Another choice is to get one of those brake bleeder "tools" like the "mini mighty vac" that can suck and or push the brake fluid thru the system.
The push thru or back bleeding technique is really helpful when just changing out the master cyl as you can force the clean, air free fluid, up in to the master cyl with out putting air in to the lower part of the system.
Just keep at it with what you have already started, as some times the master cyl can be a bear to get bleed.
Try the tapping trick to see if you have any air bubbles hiding behind the rubber flap at the bottom of the "fluid tank". You can even take a small, non sharp probe, like a #0 Phillips screw driver and open the flap a little to help the air get out. Just move the flap a little in all directions to look for air.
Hope this helps. bob
2003 Polaris Predator / 2004 KTM 525 exc 6 speed motor.
570 Thumper Racing kit w/ 12.5 - 1 CP piston.
Head ported by Thumper Racing w/ new intake seats done by Pro-1 racing.
Stage 5 cam ( Custom design by Thumper Racing )
AC bearing mod.
Oil system mod by DJH.
KW valves ( stock size )
* #100 CDI dirt bike CDI.
42 mm FCR carb by Walt/ Fast64ranchero. ( SX carb = No TPS )
Trail Tech -10 oz flywheel. ( Stock is 30 oz/ trail tech = 21 ozs )
Mino water pump. Full flow set up, no T-stat.
PB Oil cooler.
Custom modded intake. Uni filter/ D2 moto adapter on a modded Predator intake tube.
KTM dirt bike header connected to a modded PP/ White broes muffler w/ turn down tip.
( Soon to have a KTM Bill modded CT racing full exhaust system. )
Tusk Clutch kit.
Honda thumb throttle.