Yeah, you’re right… I was thinking of distance from the pivot bolt for move leverage… But really the “fulcrum” is where your foot goes…
So in that case, OP should move the bolt DOWN like you suggest 
Fulcrum=pivot point, not effort point. The closer the effort point is to the fulcrum, the greater force and less distance it takes.
That is true only if the load is on the opposite side of the fulcrum (pivot point). When the load and the work points are on the same side of the fulcrum the closer the load is to the fulcrum than the work point is, the greater the distance and less force is required for the same amount of work.
What you are saying is different than what I said, and both are correct. I specifically spoke of only moving the effort point. That always increases effort and decreases distance as it get closer to the fulcrum if the load and fulcrum are held constant. Holding those constant was implied when I didn’t mention them.
Okay. Got back to working on the kart only to discover I’d lost pressure in one line. I opened up the caliper after some bleeding (which yielded no results) only to find one of the seals had perished. Bits of seal all throughout the piston chamber.
Having had enough, I decided I would just rebuild the whole system to leave no margin for error.
(For reference, I’ve been having braking problems a lot longer than this post has been up.)
Rebuilt the master cylinder and caliper completely, managed to get pressure back and regained enough braking to take my kart to the circuit!
I ended my first stint after 10 minutes only to find fluid had leaked through the caliper seals all over my pads and rotor.
Seals I’m using are suitable for ‘‘BS6’’ systems. I can’t find any information on what connotates a BS6 system over a BSD and SA-2 system but other websites selling the same seals assure they are fine for all three.
In which case am I using the wrong fluid? I ask this because I know that DOT 5.1 is standard for BSD systems, and by that logic, the BS6 + BSD + SA-2 seals I’m finding should all work fine with that fluid?
I apologise for my lack of knowledge in advance as well, still relatively new to the world of owner driver karting.
Definitely strange. Do you think you could have nicked a seal during assembly? I run the BS6 brake caliper and use Dot 5, the silicone based fluid and never had an issue with leaks. Only reason I have had to rebuild the system was when my caliper pistons were not returning freely.
When I was ready for the rebuild, I called the guys at Comet Kart Sales to ask what fluid to use. I may be mistaken, but I think starting around 2017 OTK switched from the silicone based fluid to the water based fluid. Dot 3,4 & 5.1.
Try make the pads more close to the brake disk. Take a thin aluminum or metal foil and put it in between the pads and the brake calipern. I made a video showing how to do it.
(sorry for my bad english lol)
I also read that in some modern brake sistems it just adjust by itself, but in my older kart (not on the video) I had to adjust manually with the aluminium foil. Before do the manual adjust, make sure that the disk is centered. I hope it helps you!
Caliper seals were both incredibly rounded off on one side which would explain the leaking. This was after 7ish minutes of track time.
I’ve rebuilt the system with new seals yet again along with some DOT 5 fluid as opposed to DOT 5.1 after cleaning everything out.
Haven’t had any problems thus far after the last rebuild but it’s not like the karts been under any load sat on its trolley. I have a test day this Sunday so I suppose I’ll see how it performs then.
My caliper is self adjusting. Original issue was just down to dirty pads and rotor which I had overlooked.
Think my rotor is ever so slightly off center so that isn’t going to help but I’ll sort that next I go work on it.
My rotor was off center in the end causing the pad on one side to bind. The rotor carrier seems stuck to the axle as I’m really struggling to move it over. I did manage to get it centered after a bunch of convincing but the pad is still binding!
After closer inspection it looks like the piston isn’t retracting on its own like the other one is despite the rebuild. Swapped both pads round, bled some of the fluid out and kept resetting the piston but it would always push itself out straight back into the rotor again.
I can assure you I’m not overfilling the master cylinder as well either.
I’ve gone from no braking to too much braking. 
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Bruuuuuuh . See if the springs in the brake caliper are still there holding the pads. In motocross bikes you don’t have this springs, and one day I removed them from my kart just to see if they are useless or not, and I had the same issue than you.
The springs is located inside the master cylinder. When you let off the brake pedal, the spring pushes the piston back to rest. Check that both master cylinder springs are the same length.
An easy visual examination of the T bar at the end of the brake rod should tell you if both pistons are returning the same amount.
Looking at parts A/B, the two push rods should stick out equally from the master cylinder when at rest. If they don’t, open up the master cylinder and start checking things.
His caliper has springs which are connected to his brake pads, that’s what he was referring to.
But I will check this regardless so thank you for the suggestion!
I know. I was pointing out that the OTK system is not technically springless. The caliper is, but the Master Cylinder is not. If the pistons in the master do not return equally, then one pad will not return equally either.
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