To drill my brake rotor or not to drill my brake rotor???

[m511y]

Drilling the rotor was never the plan for my CB350 project. I think they look great, but my opinion is that breaks with more surface area stop better. People will go back and forth about how drilling and slotting rotors releases the buildup of gasses and helps them perform better under extreme braking conditions. I'm not racing my bike so for me it really just comes down to looks vs. function.

Although a drilled rotor was never a part of my build plan, I am now considering it. A very nice industrial drill press has found its way in to my home and I also just happen to have a spare CB350 rotor lying around. A while back I came across this link and it gives detailed instructions on how to drill a rotor.

http://www.anubiscycle.com/cross-drilling-rotors.htm

So I'm all set to go. I have the press, bits, countersink, cutting oil, and I have mapped out my drill pattern. My issue is that the more I think about doing this the more I think it is a bad idea. I'm going to take a 40 year old cast iron rotor, drill a bunch of holes in it, install it on a wheel that will spin at high RPMs, and apply extreme force and heat repeatedly. If I do go ahead with this and the rotor cracks, it won’t end well. There will be flying shrapnel from the rotor lined right up with my torso. If the pieces of metal don’t hit me and if the front wheel doesn’t lock up, then I’m still screwed because I won’t be able to stop. The worst part is that I would have done this to myself.

I use the phrase "Just because you can, doesn’t mean you should" a lot. Is it worth putting my life at risk for a self made cool looking rotor? Or am I just being a little girl about this?

 

[sxecafe]

I dont think it would be that big of a different in braking power. At least not enough that you would notice. The thing to keep in mind if that people that race have their rotors drilled/slotted and they brake alot harder than you ever will.

The thing that deterred me from drilling is that you couldnt reface them afterward and if I burred the rotor I would be eff'd.

 

[m511y]

I dont think it would be that big of a different in braking power. At least not enough that you would notice. The thing to keep in mind if that people that race have their rotors drilled/slotted and they brake alot harder than you ever will.

The thing that deterred me from drilling is that you couldnt reface them afterward and if I burred the rotor I would be eff'd.

Using a countersink bit to chamfer the holes would solve the burred rotor issue.

 

[Rocan]

drilled rotors perform better in the wet... THATS when gas builds up under the pad, as the gas is steam.

you wont risk your life with a drilled rotor. long as you take the time to do it right, and balance your rotor afterwards, youll be fine.

The way i look at it is this... if there wasnt a benefit, bikes today would not be being sold with drilled rotors... :



as for myself, having drilled 122 holes (twice, as i pilot drilled first), i would not do it again as its time consuming. i would send them to that company for 50 bucks and be done.

or, if i find one, invest in a rotary table. then i wouldnt mind doing it.


make your drill bits diameter less then that of the thickness of the rotor, and you have more surface area, which, if you dont go overboard with the holes, will improve cooling when your OFF the brakes. when your on the brakes, they will heat up a bit faster as theres less material to act as a heatsink.

 

[Swapmeet Louie]

drilled rotors perform better in the wet... THATS when gas builds up under the pad, as the gas is steam.

you wont risk your life with a drilled rotor. long as you take the time to do it right, and balance your rotor afterwards, youll be fine.

The way i look at it is this... if there wasnt a benefit, bikes today would not be being sold with drilled rotors... :



as for myself, having drilled 122 holes (twice, as i pilot drilled first), i would not do it again as its time consuming. i would send them to that company for 50 bucks and be done.

or, if i find one, invest in a rotary table. then i wouldnt mind doing it.





make your drill bits diameter less then that of the thickness of the rotor, and you have more surface area, which, if you dont go overboard with the holes, will improve cooling when your OFF the brakes. when your on the brakes, they will heat up a bit faster as theres less material to act as a heatsink.

Well' spoken...

 

[rockcitycafe]

Drilling the rotor was never the plan for my CB350 project. I think they look great, but my opinion is that breaks with more surface area stop better. People will go back and forth about how drilling and slotting rotors releases the buildup of gasses and helps them perform better under extreme braking conditions. I'm not racing my bike so for me it really just comes down to looks vs. function.

Although a drilled rotor was never a part of my build plan, I am now considering it. A very nice industrial drill press has found its way in to my home and I also just happen to have a spare CB350 rotor lying around. A while back I came across this link and it gives detailed instructions on how to drill a rotor.

http://www.anubiscycle.com/cross-drilling-rotors.htm

So I'm all set to go. I have the press, bits, countersink, cutting oil, and I have mapped out my drill pattern. My issue is that the more I think about doing this the more I think it is a bad idea. I'm going to take a 40 year old cast iron rotor, drill a bunch of holes in it, install it on a wheel that will spin at high RPMs, and apply extreme force and heat repeatedly. If I do go ahead with this and the rotor cracks, it won’t end well. There will be flying shrapnel from the rotor lined right up with my torso. If the pieces of metal don’t hit me and if the front wheel doesn’t lock up, then I’m still screwed because I won’t be able to stop. The worst part is that I would have done this to myself.

I use the phrase "Just because you can, doesn’t mean you should" a lot. Is it worth putting my life at risk for a self made cool looking rotor? Or am I just being a little girl about this?

no benefit to be found, based on actual racing data, so skip it and save yourself the money and headaches. if you want real stopping power, get a modern front disk brake