I just went out for the first practice on Sunday with my just purchased 2nd hand kart.
During cleanup after running (around 1H overall) I’ve noticed that almost all disc screws were loose and even after fixing them, disc was not really centered into the caliper. Pad on the right is now much more worn than the other as well.
Previous owner said me that he replaced the pads before sale so they were new. Not sure about the position of the disc because I haven’t checked it. Should I just reposition the disc in the middle of the caliper or there is something else that should be checked?
I’ve found that it’s really easy to lock up as well, but I should have fixed it shortening the connection rod to master cylinder, because pedal braking point was a bit too far losing foot sensibilty.
wait…what disc screws were loose?
Red need to be loose, the disc needs to float.
Then you loosen blue. Press pedal and keep it pressed, center the hub so it’s centered, then tighten blue
Red were loose, but even if now they are tight, the disc still moves a bit because it’s thinner than the hub which is similar to this.
That looks like a floating disk setup where the disk will be free to move a certain amount. Depending on the system, the six disc retaining bolts may also move with the rotor.
I would first want to make sure the whole axle isn’t shifting or moving. Check your chain alignment if that is off too then your whole axle moved. If the axle didn’t move then I would say your brake hub has moved.
There appear to be some issues in your first pic. I can’t tell what I am seeing but it looks like the caliper mount is loose or bent or both? (silver object between the rotor and the bearing carrier) The brake rotor should be centered on the caliper and usually floats or moves to allow the axle to move with the chassis as it flexes.
Others have spoken about the disc floating so that’s sorted. Regarding the easy lock up - try different grades of pad until you find ones you like.
For brake modulation you could lower or raise the brake rod at the pedal.
Higher setting gives you more leverage and lower less, play around and see what you like
Looking at the picture caliper bracket may look a bit bent, but it’s straight and axle it’s still fixed so probably the disc was already out of position.
Thank you all for the feedbacks. I’ve also seen some versions of my chassis with two master cylinders connected to both sides of the caliper, is it worth upgrading or difference is minimal for club usage?