Topic: Drilling Rotors

[ProTeal55]

Hey ProTeal, how difficult is it to set up dual discs? BTW, I don't think I ever got back to you about Triple O. He does great work  but was really pricey, those Italian bike owners must like to spend $$$. I worked with a guy who recommended Motoworks. I am really trying to do as much work myself as possible (this is hard since I live in the city and don't have a garage to work in).

From what I hear Fred @ Triple-O has closed down his shop to pursue other things. Motoworks is the next place I would recommend for you to get your bike up and running the best it can be. I have been dealing with them more and more, and they are actually an event sponsor of the upcoming Mods Vs. Rockers III event this coming July 16th (u better be their  )

[super pasty white guy]

Ok, I'm just wondering-  Why not send them to ElCheapo?  I really do get the "doing things myself" thing, but his price seems crazy good. 

http://www.anubiscycle.com/services.htm

dave

[Dougy Dougy Dune Buggy]

ProTeal,
I have the rotor template at home & can send tonight if you need it, it is 12:30 p.m. Here in Cali, it would be about 5 more hours
Lemme know,
DWYJ

[RSV12K]

I gotta get behind the white guy. Having someone else do it is way better. You're going to chew up at least a few bits doing it yourself. I had a guy who runs a machine shop out of his home garage do mine, and I paid something like $35 apiece (had some other stuff done too, so we agreed on a price for everything and not per item). The other thing is that with the machinery a pro uses you can play around with various hole patterns and sizes, see the results on screen and then just let the machine do the work. I know if I did it on my own, it would have taken forever and the results would have looked like crap.

[Rocking-M]

Anyone got a template for the 750f rotors? I think I'll do a set myself too!

[Terry in Australia]

Here's some I did a few weeks ago, the smaller hole (6mm) disc is for Ben Fahey for his CB350 Racer, and the other two with 10mm holes are for my K1. (the front wheel on my K1 is actually borrowed from my GS750 Suzy)

I used my Taiwanese Mill/Drill with it's 1 HP motor, and a "rotary table". the beauty of the rotary table is that you just mount the disc on the table (after you've turned a "hub adapter" on your lathe) and there's no need for any template at all, I just punch a hole thru at every 20 degrees, and it's done.

I used Cobalt drill bits, Ben's disc has 85 holes in it and the best lube I tried was his suggestion, dish washing liquid! It worked really well, I did try several other (expensive) cutting lubes, but in the end I needed to constantly re-sharpen the bits on my grinder, so I went back to the Palmolive option, and it was fine.

My two discs (only 51 holes each) required the sharpening of one bit twice, and the other bit (which I didn't need to use, but did anyway) did about 20 holes but will need sharpening before I do any more. I buggered my counter-sink bit in the process, (HSS really isn't up to drilling "work hardened" stainless steel) so when I can find a cobalt item, I'll finally finish them! Cheers, Terry.

[78CB750F1]

I have seen several services for cross-drilling and they vary a lot in hole patterns - can anyone provide feedback from the services below and suggest the optimum drilling pattern?  This is for single front and rear disc on a 76 CB750F1 with a modern Nissin front master cylinder.  The 180 hole pattern from Cycle X looks great but is that overkill?  When a rotor gets cross-drilled, should it be resurfaced as well?

CycleX: http://www.cyclexchange.net/Honda%20Page.htm - drilling only - 180 hole pattern

Anubis Cycle: http://www.anubiscycle.com/services.htm- 3-2 staggered pattern

Ebay seller: http://cgi.ebay.com/ebaymotors/HONDA-CB500-CB550-CB750-BRAKE-DISC-MACHINE-SERVICE_W0QQcmdZViewItemQQcategoryZ111111QQihZ020QQitemZ300043567130QQrdZ1 - resurfacing and 72 hole pattern

Thanks for your input.

[flatblack]

The main thing I know about drilling rotors is for the holes to be staggered so that all of the pad's surface sees solid rotor most of the time. Chamfering isn't all that important as long as the holes are deburred.

I haven't tried any of the drilling/resurfacing vendors, but plan to next time I have a wheel or two off (i.e., when I'm not working on bikes with drum brakes).

HTH...

fb

[nickjtc]

Speak to Tom at Anubis, aka el Cheapo. He has a good rep for excellent work.

[jrrobertsjr]

Second on Anubis.

I like the fact that he describes the dangers of over drilling.

Plus, he helps out on the forum as much as he can.

[bgfootball67]

Cast my vote for Cycle X Change, those guys have helped me out quite a bit.  I have their drilled rotor and am getting ready to rock it once the cafe is totally together.....

[Bikebuff]

Third on Anubis.  I had him do 2 rotors for my dual disc conversion I'm doing.  I dropped them off at his shop and he mailed them within 3 days.  Resurfaced, drilled and he also fogged the center section black, as some of the previous black paint was starting come off.  Very reasonably priced and a reasonable (and funny) guy to talk to.

My 2 cents.


Prost!

[c_kyle]

Third on Anubis.  I had him do 2 rotors for my dual disc conversion I'm doing.  I dropped them off at his shop and he mailed them within 3 days.  Resurfaced, drilled and he also fogged the center section black, as some of the previous black paint was starting come off.  Very reasonably priced and a reasonable (and funny) guy to talk to.

My 2 cents.


Prost!

What was the price for all that?  The site says $25/pair, or $35/single rotor for drilling.  I didn't see any mention of resurfacing them, though.  Anubis sounds like the best bang for your buck.

[tsflstb]

Just to share the wealth, I used the third option you posted...the ebay seller is a member here.  He has the equipment to do really nice work.  The grinding process leaves a perfectly flat surface for the pads to grab.

[francisew]

Can anyone post how much it costs including the surface grinding?

Francis

[MoTo-BunnY]

I'm going to use his rotor services as soon as I can scrape together some more fundage, because he's here in Portland and maybe I can save a bit on shipping and drop it off?  He sounds like he is ALL into SOHC bikes - read his eBay 'ME' page. .  . . 


SELLER:  smw70ss  1212 feedback / 100%!

view seller's items
for sale

PRICE: $44.99 starting bid / $49.99 buy it now  +$9 UPS shipping

VERBATIM FROM AUCTION:

"This auction is for surface grinding one motorcycle brake rotor. These rotors are stainless steel and cannot be turned on a conventional automotive brake lathe. All work is performed on a rotary surface grinder to exacting tolerances. Newer style floating rotors cannot be surface ground, only the fixed type used on these older bikes. Usually grooved or warped rotors are replaced but this process brings new life to your origonal pieces and leaves a nice finish. Simply ship you rotor after winning the auction and it will be shipped back within one week of bieng recieved. If you have multiple rotors or would like to purhcase additional services please contact me to make arrangements. Drilling is also available and is done on a dedicated mill and rotary index table using all cobalt tooling. Anyone who has tried working with stainless steel knows it is difficult to machine and wears out tooling quickly. Drilling is done in a multi step process with a 3/8" finished hole. Smaller holes are sometimes used with smaller diameter rotors. Since all work is done on precision equipment, hole placement is consistent and all workmanship is guranteed to be of the highest quality. The price for drilling per rotor is $55.00 for a 36 hole pattern, $70.00 for a 45 hole pattern (alternating rows of 2 and 3 holes) and $85.00 for a 72 hole pattern."

[Jv550]

Anubis did a great job on mine too - quick, cheap and great workmanship. But I think I had read somewhere on here that he lost his shop or something?

[newcbguy]

i dont have a good template but I did mine with a degree wheel from the web and center punched every 20 degrees.

[Alan F.]

Here's the old template for drilling a cb750 rotor that was emailed to me many, many years ago by Speedfrk (Darren P.) from the old Greenspun days, it consists of two jpg's that you should print out and tape together, as well as a copy of the original instructions from the originator. 

Enjoy!

[rlarkin70]

I like that slanted pattern. So what kind of drill bit did you use? How many do you go through per rotor? =)

[736cc]

  Just had mine swissed by speedracer741; they have 72 holes per disc

[MikeD718]

i used good old fassion geometry to figure mine out. 90 holes per rotor using 3/8 bit, about 3 bits per rotor.
 

[kmart550]

Does drilling the rotors affect the pads at all?  Like do they wear faster? 

[Alan F.]

I only used one 1/4 inch bit to drill my two rotors, it was a good quality bit and was borrowed.  You've just got to use the correct speed, feed rate and lots of oil.  Best to drill them on a windy day as there will be lots of smoke produced by the cutting oil.  I changed the 3-hole pattern a bit, moved the holes over and added a fourth row, took off about a quarter pound per disc.  Then I hit the swept area with an orbital sander and some heavy grit paper, came out great.

The holes don't really affect the pads much, the holes aren't for increasing friction, what they will do is reduce squeal by providing a place for the built up gasses that the pad friction creates, to escape to.  I don't ride much in the rain, so I can't say if it improves wet braking.

[KB02]

The holes don't really affect the pads much, the holes aren't for increasing friction, what they will do is reduce squeal by providing a place for the built up gasses that the pad friction creates, to escape to.  I don't ride much in the rain, so I can't say if it improves wet braking.

It also helps to reduce brake fade by helping the rotor to cool faster. (and looks cooler, too  )

Here's the old template for drilling a cb750 rotor that was emailed to me many, many years ago by Speedfrk (Darren P.) from the old Greenspun days, it consists of two jpg's that you should print out and tape together, as well as a copy of the original instructions from the originator. 

Enjoy!

That's the pattern I used on my disk, too.