I have a Righetti Ridolfi caliper and master cylinder on a kart and there is more of a gap between the pads and the rotor than I would like. Do I shim the pads or is there another sort of adjustment for this? Also, the pads don’t start to move until about half of the master cylinder stroke. It’s been bled over and over. Is this normal? Is there a way to adjust this to make the brakes hit sooner?
Yes, shims are available. If the pads are worn you should consider replacing them instead of shimming. When was the last time the system was rebuilt? If everything is working correctly the caliper should start moving as soon as the master cylinder is actuated.
When you bleed the brakes, take the rod from the pedal off at the master cylinder lever and make sure the lever has returned ALL the way back against the MC, then go ahead and bleed the brakes, that should fix your problem.
the whole system was new about 3 months ago (caliper, pads, master cylinder). There is a definite gap between the pads and the rotor (roughly even on both sides, so it’s not that the rotor is not aligned to the caliper). I’ll try removing the rod but it looks like the m/c lever is all the way seated.
I think he means raising the linkage rod to a higher position on the pedal. That will get the pads to make contact sooner but there will be less pressure on the pads for any given amount of pedal pressure.
Some karts have a larger gap between the pads and rotor by design. If your satisfied that all the air has been bled out and the pads are not worn I would set the pedal back stop where you want it and adjust the linkage rod shorter. That will get rid of the excess pedal travel. There needs to be some free travel or the brakes will drag when they heat up.
How much of a gap is there? Does the pedal feel solid once the brakes lock? Did you try setting the linkage for faster travel? Do you have allot of experience bleeding brakes? It’s easy to get air trapped in the system.
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
41 years karting experience