Rotor prep before new pads. squeal/howling

[rebar]

I cant find the info I read a while ago about rotor prep before new pads. I think it was recommended to sand the rotors with a very fine grit wet/dry paper to remove any residual pad material, and clean well with brake cleaner before new pads.:confused2:

Would this help my rear brake stop howling? Prevous owner installed new rear pads and said it started howling after the new pads. And after I installed HH pads on front of my stock bike, I get a little squeal the last 5 feet of stopping travel. Not as annoying as the rear brakes on my keihin bike though.

Thanks

 

[maleko89]

That may help but also wash the waters in dish soap and warm water.

 

[gamorg02]

chamfer the leading edge and ask morley about his graphite 'stop squeal' stuff. it works wonders.

 

[rebar]

That may help but also wash the rotors in dish soap and warm water.

Easy enough thanks..

chamfer the leading edge and ask morley about his graphite 'stop squeal' stuff. it works wonders.

Can someone explain how to correctly chamfer the leading edge please?

I did a search but only came up with chamfering the holes.

 

[gamorg02]

Easy enough thanks..




Can someone explain how to correctly chamfer the leading edge please?

I did a search but only came up with chamfering the holes.

take a file and the leading edge of the pads. instead of it having a 90? angle, make it have a small 45?

 

[rebar]

take a file and the leading edge of the pads. instead of it having a 90? angle, make it have a small 45?

Ah.. Thought you were talking about the leading edge of the rotor.

Thanks..

 

[gamorg02]

oh god no. sorry!

also i see your confusion. hard to find the leading edge of a CIRCLE!

 

[rebar]

The pads are installed but Im not impressed with the location of the rotors on my Ego tripp wheels. left side needed a .045" washer between the caliper and fork mount and the right side need .19" (4 washers!) to get the caliper as close as I could to center. The caliper barely slid over the rotor with the new pads making measuring the gap between the caliper and fork easier.

This inaccuracy must have contributed to hot rotors after my first 4 mile ride. To hot to hold but not touch.

How hot can the front rotors normally get in stop and go traffic?

Kevlar pads don't have the power of the HH but feel good and quiet.:clapping:

 

[VMAX NV]

take a file and the leading edge of the pads. instead of it having a 90? angle, make it have a small 45?

The leading edge being the edge that comes in contact with the disc first?
Like the edge your disc lock would bang into if you left it on and tried to drive away? (what, no one else has done this?)

 

[MaxMidnight]

Quote "How hot can the front rotors normally get in stop and go traffic?"

Without wishing to state the bleedin' obvious, it depends upon how much you use your brakes and from what speed.

You are stopping a 280 lb plus bike plus the weight of the rider.

That is an awful lot of kinetic energy (the mechanical energy that a body has by virtue of its motion) and it needs to be converted to dissipate it. When applying the brakes this will normally be heat (or in the case of your back brake heat plus noise).

One other factor to consider is that the kinetic energy increases with the square of the speed. Double you speed and there will be four times the kinetic energy. If you are interested the formula is K = 1/2 x mass of object x velocity squared.

If you watched the recent night time Moto GP you could see that the front disc's were red hot under braking!

So depending on your speed and how hard you brake I would expect the disc's to get hot. The more you use then the less time the heat has to dissipate.

When fitting new pads use the opportunity to check the caliper pistons. Clean off any accumulated crap - use some brake fluid and an old toothbrush. Make sure that there is not a build up of corrosion that will prevent them from returning into the caliper bore. Carefully remove any that is present.

Push the caliper pistons back Into the bore to make sure they are free. Wipe off any excess brake fluid

Resist the temptation to pull the brake lever unless you have a piece of wood between the pistons to prevent them popping out! :Sick:

Bust any glaze from the disks with some fine wet and dry. Chamfering the pad or a small wipe of Copper Slip on the back of the pad can help reduce squeal. Also consider a different pad material.

On a flippant note, the best way to eliminate the squeal completely would be to stop using the rear brake? :clapping:

 

[rebar]

The leading edge being the edge that comes in contact with the disc first?
Like the edge your disc lock would bang into if you left it on and tried to drive away? (what, no one else has done this?)

Imagine your pads as snow skis. You wouldn't go to far without the curved up portion on the front.

I don't now if it helps. but I imagine it catches more dirt and guides it under the pads.

 

[gamorg02]

The leading edge being the edge that comes in contact with the disc first?
Like the edge your disc lock would bang into if you left it on and tried to drive away? (what, no one else has done this?)

exactly

Imagine your pads as snow skis. You wouldn't go to far without the curved up portion on the front.

I don't now if it helps. but I imagine it catches more dirt and guides it under the pads.

i can see the thought but i don't think it guides any more under than would normally. i didn't see any negative side effects of it.

 

[4gasem]

Many car brake pads come with a chamfer on both sides when new. I have a set of HAWK HPS's set to go on my G8 that are chamfered on both ends.

 

[Rusty McNeil]

I don't think the chamfered edges on pads do anything to help performance, it's only to cut down on noise....just my opinion tho' I could be full of shit....:ummm:

I never do anything to the rotors other than wipe them down with alchohol to get the grease and what not off of them so it doesn't hose up the pads...There probably is a more correct way to do it I imagine..After all, I always turn rotors on a cage before installing new pads...

Never had an HH pad in the rear that didn't groan or shudder at low speed right before stopping...never squealed though. I quit running them and went back to regular organic pads in the rear.....I rarely use the rear brake anyhow...I don't see the point in upgrading the rear calipers and stuff except for that it looks cool....lookinng cool don't hurt though..


Here is a question.

I've not seen any WAVE rotors that were affordable unless they were non-floating..Is that really an upgrade over stock or is it a downgrade with the benefit of having cool looking rotors? Or is it that floating rotors aren't that important??

I want wave rotors damnit, just don't have $1000 to spend for a full set...

 

[gamorg02]

I don't think the chamfered edges on pads do anything to help performance, it's only to cut down on noise....just my opinion tho' I could be full of shit....:ummm:

I never do anything to the rotors other than wipe them down with alchohol to get the grease and what not off of them so it doesn't hose up the pads...There probably is a more correct way to do it I imagine..After all, I always turn rotors on a cage before installing new pads...

Never had an HH pad in the rear that didn't groan or shudder at low speed right before stopping...never squealed though. I quit running them and went back to regular organic pads in the rear.....I rarely use the rear brake anyhow...I don't see the point in upgrading the rear calipers and stuff except for that it looks cool....lookinng cool don't hurt though..


Here is a question.

I've not seen any WAVE rotors that were affordable unless they were non-floating..Is that really an upgrade over stock or is it a downgrade with the benefit of having cool looking rotors? Or is it that floating rotors aren't that important??

I want wave rotors damnit, just don't have $1000 to spend for a full set...

u know whats nice, the new type of rotors available that toxic has on her. u can get a full set (2 fronts 1 rear) for i think under $400. i've got my eye on them down the road. they are SICK loooking! they're not on ebay right now but will be

i also agree on the purpose for chamfered edges

 

[4gasem]

I don't think the chamfered edges on pads do anything to help performance, it's only to cut down on noise....just my opinion tho' I could be full of shit....:ummm:

I never do anything to the rotors other than wipe them down with alchohol to get the grease and what not off of them so it doesn't hose up the pads...There probably is a more correct way to do it I imagine..After all, I always turn rotors on a cage before installing new pads...

Never had an HH pad in the rear that didn't groan or shudder at low speed right before stopping...never squealed though. I quit running them and went back to regular organic pads in the rear.....I rarely use the rear brake anyhow...I don't see the point in upgrading the rear calipers and stuff except for that it looks cool....lookinng cool don't hurt though..


Here is a question.

I've not seen any WAVE rotors that were affordable unless they were non-floating..Is that really an upgrade over stock or is it a downgrade with the benefit of having cool looking rotors? Or is it that floating rotors aren't that important??

I want wave rotors damnit, just don't have $1000 to spend for a full set...

I have solid fronts. Floating rotors are really only necessary for track duty.

I did it for looks. They're OK, but don't do it for performance. Stock is hard to beat, unless you're working with pre '92.

The rear rotor saved 1 pound over the stock rotor.

Chamfering keeps them from chattering...

Chris