Hi there,

I'm building up a monstercross type bike. I have an issue with the front disc rubbing when i'm sat on the bike. When there is no load there is no disc rub. Just wondered if someone here could diagnose and help me resolve this. I am beginning to wonder if the lower fork bearing race might be out of alignment forcing the wheel out of of true or the wheel? The problem happens in both laternal and forwards movement.

Parts
160mm rotor, SRAM road Rival caliper on a 160-180 adapter plate. Hydraulic hose as yet unattached. 2.6" tyre, 29er mtb wheel rim, carbon mtb fork with QR drop outs. The front wheel bearings feel tight and both the wheel and the rotor are true.

Any ideas?