no front brake pressure

In the midst of building my CRF 150F supermoto track bike.  just got the front brake mounted up as im nearing the end of my build and im running into a problem.  I got a 250mm rotor and relocation bracket, a cr250x front caliper and master cylinder, and a stainless line.  I installed everything, reverse bled the system, even took off the brake line at the MC and gave it a few pumps with my thumb over the outlet to check for pressure there(yup it squirts out past my thumb).  when i go to bleed the system i just pump away, no pressure builds, and when i open the bleeder with the brake held tight, its all fluid that just seeps out (no bubbles) with no pressure behind it.  Suggestions?  The only suggestion ive got that im going to check tomorrow is that if the caliper is cockeyed at all on the rotor I know someone that had this same problem with the front brake not building pressure.  Tomorrow i will look into this.

Sometimes on a new system I have that issue. I'll vacuum bleed and seal up the system. Then I'll zip tie the lever back against the bar and leave it for a few hours,sometimes overnight. 80% of the time it does the trick. Also shows any pinhole leaks that may be sabotaging the job.


On my Tuono I have to remove the caliper and mount it on top of the rotor to get the bleeder screw at the highest point in the system.

Edited by T.RexRacing

Turns out the MC was bad. Swapped one in I had laying around and it works fine.

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