Dear friends
Just upgraded my Rocker'09 front brake system to PM 6 piston caliper,single rotor and master.Everything fine(no 'spoongy' or deep travel brake lever) but when I pull the brake hard,handle bar pull to the right side and there is sound of hissing/ sizzling on the brake system when I hold the brake lever (bike moving) and gone when release.Quite sure no air trap on the system because I did 'bleeding' the brake many times.
Any advice? Sorry for my 'bad English'

 

Did you use a vacuum bleeder?

Describe how you bled your brakes.

 

Hi Prot..
Reservoir cap and the rubber cover off reservoir tank.Pull and hold brake lever,open up bleeder nut,close bleeder nut then released brake lever.Repeat few times until oil that came out from bleeder nut free from air bubbles.
No,I dont use a vacuum bleeder
Thanks for your reply and have a nice weekend.

 

Is your hissing sound coming from the actual brake pads / rotor area? if so this may be quite normal especially with good compound pads. My Big Dog chopper does this, PM brakes F/R with EBC HH rated pads. My Breakout also does this on the front brake with the EBC HH pads. but you are stopping good correct?

I'm not sure what to make of the bike handlebars pulling to right though on braking. that almost sounds like an alignment issue. have you double checked the rear wheel alignment?

 

Hi LADog
Thanks for your respond.
Confirmed hissing/sizzling sound not from brake pad touching rotor. The hissing sound more like when we deflating tire.There is no oil leak on the caliper,master or hose and the brake perform well.
Have a nice weekend..
Teo

 

I asked a HD mechanic who said the hissing sound is normal and has to do with the air held in the drilled rotors when applying the brakes. ?

 

Teo- I think you need to try and identify where the sound is coming from, e.g. up by your hand or down by the wheel? there is really nothing physical going on that could make that type of hissing sound other than the pads on rotors- or maybe a high pressure fluid leak, but you'd know about that in a heartbeat.

either that or you have a snake living under your seat or something??

yes that is very common with drilled or slotted rotors, but the better rotors have beveled edges on the drilled holes or slots which reduces the hissing noise. non-drilled or slotted rotors can still make that sound to some degree depending on the type of pads, rotor and caliper combo.

 

Naaah, Idunno. I'm gonna call horseschizz on that. I've never had that with drilled rotors. I think they're all slightly beveled or they'd tear up the pads like a cheese grater. I think what he's hearing is a diffenence in brake pad compounds. Maybe the the original pads were organic and the new PM's are sintered or semi-metallic.

In any case, take a damp sponge, sprinkle on some Comet cleanser or some other slightly abrasive kitchen cleaner and dab it on both sides of the rotor then ride it around the block. The cleanser will break the glaze on the rotor and smooth out the pad surfaces then maybe the sound will go away. When the brake cools he can rinse off the excess cleanser. But then I've been riding Shovelheads all my life so what do I know.