Hot Brake discs

[Constructicon]

Hi people,

 

I got a prob with my ride. (Fazer)

 

The brake pads for both front and rear were changed a few days ago and I noticed that the brake discs became hot after a ride. Noticed it when I accidentally touched it while pumping the tyres.

 

I stopped the bike to let the discs cool down then ride off again and stopping after 5 mins without any using the brakes(Only engine brake) .

Touched the discs, it's warm. So I suppose the pads are in contact with the discs all the while, even without using the brakes.

 

Is this normal for new brake pads, or are the pads set too close to the discs?

 

Please advise.

Thanks.

[greysnail]

It normal if u juz changed the new pad.This process is called bedding in.Its mean to get seasoned as the new pads are fresh.it will go off sooner.Dun worry and ride as per normal.

[Constructicon]

Thanks for the prompt reply man!

 

Cos the discs are hot *ouch* even when I am not utilising the brakes and I am worried it might warp the discs and cost me a bomb then.

[greysnail]

No problems.

[bladeboy]

if after the bedding in still contact than check ur brake piston seal mine got stuck b 4 cos the rubber harden too old liao

[Constructicon]

Er,how long does it takes to bed in the brake pads?

[bigboystoys]

Hi,

 

I don't think there's a problem with your brake pads or discs.

The pads are always touching the disc even when you do not apply brakes.

This constant 'rubbing' will definitely build up a bit of temp. As long as you do not feel that there's a 'braking' feeling when you're coasting, then it's fine.

 

Just to add on, the 'rubbing' part will build up temp and then the pads, fluid and discs will expand a bit thereby increasing the 'rub'. But not to worry because your fluid will be pushed back to the master cylinder reservoir. It's not easy pushing the fluid back up to the reservoir due to the tiny hole of the compensating port but it'll be pushed back. You can try by comparing the braking point when the disc/pads are cool and after 10mins of riding around.

 

Of course, there could potentially be a problem with your brakes. The pistons in the calipers may have seized due to rust or dirt build-up. I used to have this problem where my pistons have seized in the calipers. When it's cool, the brakes are fine but when the 'rubbing' builds up the temperature and everything starts to expand, the pads are not able to push the pistons back to the calipers and that's when my nightmare started. The bike felt like it was being bogged down and I had to keep stopping to cool the brakes. Haha

 

One way of checking if your pistons are seized is to try to apply the brakes. You should be able to have some free-play in your lever/pedal. The braking point should be at about 60-70% of your entire lever/pedal stroke. If the braking point is at the beginning 10-20% of the stroke, then it means that the fluid (pressure) has been locked-in in the line and your brakes are being applied on all the time.

 

 

Let us know if you have troubleshoot it.

 

 

[bigboystoys]

On the brake pads bedding in part.

 

To bed-in brakes, you need to introduce heat to the pads slowly and bring it up to the optimum operating temperature and then let it air-cooled slowly. A couple of light braking followed by a couple of medium to hard braking should suffice. Just remember not to apply hard braking at the very beginning of the pads' life. Temperature is the key. If you applied too much temperature, you may glaze the pads or worse still, overheat the discs (though this is not common). A glazed pads will have a very shiny surface and the glazed layer must be removed or it will damage the disc. Easiest option is to throw the glazed pads away.

 

 

[Constructicon]

Hi,

 

I don't think there's a problem with your brake pads or discs.

The pads are always touching the disc even when you do not apply brakes.

This constant 'rubbing' will definitely build up a bit of temp. As long as you do not feel that there's a 'braking' feeling when you're coasting, then it's fine.

 

Just to add on, the 'rubbing' part will build up temp and then the pads, fluid and discs will expand a bit thereby increasing the 'rub'. But not to worry because your fluid will be pushed back to the master cylinder reservoir. It's not easy pushing the fluid back up to the reservoir due to the tiny hole of the compensating port but it'll be pushed back. You can try by comparing the braking point when the disc/pads are cool and after 10mins of riding around.

 

Of course, there could potentially be a problem with your brakes. The pistons in the calipers may have seized due to rust or dirt build-up. I used to have this problem where my pistons have seized in the calipers. When it's cool, the brakes are fine but when the 'rubbing' builds up the temperature and everything starts to expand, the pads are not able to push the pistons back to the calipers and that's when my nightmare started. The bike felt like it was being bogged down and I had to keep stopping to cool the brakes. Haha

 

One way of checking if your pistons are seized is to try to apply the brakes. You should be able to have some free-play in your lever/pedal. The braking point should be at about 60-70% of your entire lever/pedal stroke. If the braking point is at the beginning 10-20% of the stroke, then it means that the fluid (pressure) has been locked-in in the line and your brakes are being applied on all the time.

 

 

Let us know if you have troubleshoot it.

 

 

 

Thanks bro!

Really appreciate you input.

 

I went down to my bike shop and the good thing is the caliper pistons are not jammed.

The cause of the heat is because my brake calipers arent original (Another story )

The misalignment of the calipers to the dics caused the pad to be in constant contact with the disc at the end point of the pads, generating heat.

With some more time, the pads will be evened off. I guess I got to wait til then.

But he say the heat is still ok, no damage/warpage to the discs.

 

Thanks man.

 

Have a pleasant day/ ride.

[bigboystoys]

No probs.

 

However, I think that even after your pads are 'even' off, the heat will still be generated I'm afraid, due to the constant rubbing effect. But no to worry about this heat generated, like your mechanic said, it won't damage anything.

 

[kurarensu]

regardless of new/old pads.. the disc will always get warm/hot due to braking.. it causes heat to the disc..