c28 Brakes problem

[jrancini]

I have my sons 2008 c28 Cadet and i dont think the brakes are working at 100%. when i have it up on the stand and i give it full throttle(hpv1) and i apply the brakes, it doesnt have that clean crisp stop of the rear tires axle, i have to apply extra extra extra force on the brakes to get the rear tires to stop completly, i have compared it to other friends karts on the track an their(other karts) rear wheels stop with much less force applied to the brake. and about a month ago i replace the brake rotor and i have new pads( which by the way they wear down pretty fast) i dont think they need bleeding, maybe they need rebuilding which i will do, but my guess is that they need proper breakin in of the new pads, what do you think? can you help me on how to "Brake-In" new pads or "bedding" i think its called . thanks

jonny

[Jody Jernigan]

How much space is between the rotor and the pads?? I know they make shims to install to lessen the gap. When you are applying the brake do the pads immediately start to move or does the pedal have a fair amount of travel before the pads start to engage? If the pads don't move immediately then I would say there is a chance of air in the system or low fluid level. Simple things I know but these are questions that need to be answered to detremine where the problem lies.

[jrancini]

I do use Shims and i do try to get the pads close to the rotor, i think maybe 1/16-1/8max. and when i apply the brake the pads do move right away, i will still bleed just to make sure, however i think the problem is that when the brakes are applied fully they dont hold or slow the rotor down completly unless ALOT of brake pressure is applied, again compared to other brakes system from other karts.

[Chris Lobaugh]

I would also break the glaze off the pads and rotor with some emry paper. Are you using a secondary brake cable? If the cable is too tight it will keep the pedal and master cylinder lever from travelling as far as they should. The pedal will feel a bit soft as you described. If you are not using a secondary brake cable there is something else going on there. Is the rotor in good shape? Are the pads worn unevenly (much more at the top than the bottom)?

[jrancini]

there is a secondary brake cable , but there is enough space and it does not interfere, i just got the rebuild kit from Steve and i rebuilt the master and brake calipers and i got the new ceramic pads and it works ALOT better i think whatever it was i think it might be fixed, however there was uneveness wear on the old pads, what does that mean? the rotor is about 2 months old(brand new). is there a proper "brake in" procedure? i will remove any Glaze as you mentioned. thanks!!!!!!!!!

[Chris Lobaugh]

There is a break in procedure...fairly simple. Ease the pads up to temperature (little bit of pedal pressure at the braking zone) and then use them as you normally would at the next corner. Let the kart coast throught the next few corners, then use them normally for the next corner. Do this for 10 laps or so. I would treat the session similar to an engine break in session...keep the speeds fairly low, but, don't go so slow as to not actually use the brake pedal. The top of the pads will wear more than the bottom of the pads because of the rotation of the brake disc. When the brake pedal is applied and the pads make contact with the rotor (as long as the kart is rolling forward and not backward) the rotor will pull the top of the pads down and thus wear the top of the pad quicker than the bottom of the pads. On a full size kart I always swap the brake pads from side to side everytime I add shims. On a cadet kart (since you don't add shims quite as offen) I would suggest swapping them from side to side about every weekend or so. This will keep the wear a bit more even and should extend the life of you pads. Hope this helps.

[Matt Dixon]

Great tip on swapping the pads Chris, thanks!

[Jon]

Note: I ended up putting 2 stonger and stiffer return springs on the brake pedal and it really help me from a heavy foot on the really light "stock" return spring. It was giving me some brake pad issues.