Topic: EBC Rotors

[SOHC4 Cafe Racer Fan]

Has anyone replaced these with their stockers.  If so: (1) which model number did you use; (2) which model is your bike; and (3) did installation require any work other than a straight swap and bolt on?

I'm thinking about using these on my upcoming K2 build along with AP Calipers.

[SOHC4 Cafe Racer Fan]

bump
anyone?

[Steve F]

A picture or a link would be nice 

[fuzzybutt]

like the ones that dynoman sells?

[scunny]

http://forums.sohc4.net/index.php?topic=51179.msg543860#msg543860

[bucky katt]

i know i'm resurecting an old thread but i didnt want to clutter things up with an uneccesary thread. the page that has these ebc rotors on Dynomans site says they dont offer a rotor to fit the 1969-1976 k bikes, but i thought that all of the single disc sohc 750's used the same rotor. i have a 75 750f rotor on my k4 750 wheel on the fork sliders of unknown vintage, just that theyre newer than the early style on the k0 and not the longer ones on the late sohc f bikes. if i get all the stereo equipment sold this week a rotor is one of the things going into the bike, along with the f2 cam and some other stuff members here are selling. i have emailed dynoman again about this, lets see if i get a reply this time.

here is the statement saying what they do and dont fit


*Note: EBC does not offer a rotor to fit the
1969-76 CB750K models or
1977-78 CB750F2 models

[robe0531]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

[bucky katt]

ok but that doesnt explain why all my k components work with the rotor from an f bike

[MCRider]

ok but that doesnt explain why all my k components work with the rotor from an f bike

I emailed EBC directly about this and got the reply that they don't offer a disc for our older Ks. I have a 72K2 and a 75F. The discs look identical except... the 75 F disc is the same thickness as my K discs, but... my K discs have been thinned fairly aggressively.

Could this mean that the only difference is the thickness?

If so the EBC rotor for the 75F would fit our older Ks, just be thinner which is OK. Would like to get confirm on this. EBC simply doesnt' want to put their butt on the line for an old low volume product.

If I was to that point in the build I would almost risk buying the EBC disc to see if it would lash up. If not I'd have to eat a restocking charge to send it back.

[MCRider]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

I'd say that is correct. But the EBC rotor is for the 75,76 F which i think is the same as the early Ks, only thinner. But the thickness is why EBC won't say it fits. I think, but not confirmed.

[754]

If they fit a 77/78 K, they should fit all the other year 750s..

[MRieck]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

I'd say that is correct. But the EBC rotor is for the 75,76 F which i think is the same as the early Ks, only thinner. But the thickness is why EBC won't say it fits. I think, but not confirmed.

As a side note....EBC does have a replacement rear rotor for the 75/76F

[MCRider]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

I'd say that is correct. But the EBC rotor is for the 75,76 F which i think is the same as the early Ks, only thinner. But the thickness is why EBC won't say it fits. I think, but not confirmed.

As a side note....EBC does have a replacement rear rotor for the 75/76F

Which I think is simply the front rotor, isn't it? Too big for me.

[bucky katt]

when i get the extra cash i'm going to order the rotor and if it doesnt work out i bet someone here could use it at a nice discount.

[MCRider]

when i get the extra cash i'm going to order the rotor and if it doesnt work out i bet someone here could use it at a nice discount.

I will need one for the front of my 75 750F, so yes I would likely buy it. Or someone else. The project is a ways off, but I want it to be a one disc front end.

[MRieck]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

I'd say that is correct. But the EBC rotor is for the 75,76 F which i think is the same as the early Ks, only thinner. But the thickness is why EBC won't say it fits. I think, but not confirmed.

As a side note....EBC does have a replacement rear rotor for the 75/76F

Which I think is simply the front rotor, isn't it? Too big for me.

    No...the front and rear are different.

[MCRider]

no 77 and 78 are a little different they stick out a little more toward the fork legs i belive

I'd say that is correct. But the EBC rotor is for the 75,76 F which i think is the same as the early Ks, only thinner. But the thickness is why EBC won't say it fits. I think, but not confirmed.

As a side note....EBC does have a replacement rear rotor for the 75/76F

Which I think is simply the front rotor, isn't it? Too big for me.

    No...the front and rear are different.

OK, just wondering. Good to know.

[bucky katt]

well, i have a 75 750f rotor on it now and it works great, so i'm assuming that there is going to be no problems. which is a good thing.

[cb750k77]

here is the pic

[wannabridin]

i have a 76 GL front end, i think they have a direct swap for those that work pretty well.  hows the performance upgrades even on the stock single disc?

[cb750k77]

i never installed one on my bike but i did forsomeone else and they LOVED it stoped really well had a good feel to it deffinetly could tell...

[wannabridin]

this might be a decent alternative to one of fishheads kits.  some SS lines, new pads and rotors and you'll def. be better off.  put the money from drilling the factory rotor into this, and you'll be in business.  a full floating setup will be better than the rigid one anyday too

[MCRider]

this might be a decent alternative to one of fishheads kits.  some SS lines, new pads and rotors and you'll def. be better off.  put the money from drilling the factory rotor into this, and you'll be in business.  a full floating setup will be better than the rigid one anyday too

When I talked to EBC, they said the rotor is 15% more friction than stock. That along with EBC pads (of course), lines and fluid, yields more brake than stock. Maybe an uptick on the MC to top things off.

My FreeBird project has "minimalism" as its theme so one front disc with a fork brace is my goal.

[wannabridin]

ya, i'd rather have better stopping power, but i do like the minimalist theme you'll have!  i'm going to try and route as many wires and lines as i can on my build, just cuz it looks so much better!  so it's either twin EBC discs, or a fishhead kit...  i guess it all depends on bang for my buck!   

[Deltarider]

That EBC rotor would be my choice , certainly over mounting a second disc, in which I don't believe, the more after a member wrote recently he immediately took it off, unhappy with the extra unsprung weight.
http://forums.sohc4.net/index.php?topic=64964.msg712087#msg712087

[MCRider]

That EBC rotor would be my choice , certainly over mounting a second disc, in which I don't believe, the more after a member wrote recently he immediately took it off, unhappy with the extra unsprung weight.
http://forums.sohc4.net/index.php?topic=64964.msg712087#msg712087

I initiated a thread about a year ago about dual discs. My question related to the holes in discs affecting stopping power. I knew that it didn't but I couldn't remember why. I got the answer which then expanded to a fuller discussion of dual discs.

Essentially, adding a disc by itself doesn't increase stopping power. It takes the available power from the master cylinder and spreads it over a larger surface. THe benefit is less fade, less pad wear, and a more symmetrical feel to the fork, though this is a different subject. We had engineers in the thread with formulas and high falootin math and everything.

More and bigger holes also doesn't change the available power, it just concentrates it on a smaller area...and increases pad wear.

SO I got to thinking, for my riding style, which is fast but not hard on the brakes over and over, wouldn't I be better off going back to one brake, making it as good as it can be with a EBC rotor, pads, and maybe a more powerful master cylinder, which is the starting point of ultimate brake power anyway? Then I can enjoy the lighter front end, and lower maintenance.

If you're doing track days, or outright racing, or just want the look, then 2 discs is right.  But for a street bike, without upgrading the master cylinder and rotor material, is there really much gain?

Personal preference. I'm going to give one primo set up disc a try for my cafe racer.

[754]

Do the EBC rotors rust?

[cb750k77]

i dont think sooo i know the middle is made out of aluminum.... they might though they are made out of standard material that modern rotors our made out of..

[bucky katt]

i have a 14mm master cylinder from a gsxr750, braided stainless lines and rebuilt caliper with stainless piston

[wannabridin]

the EBC rotors are stainless steel, so no rust

[MRieck]

That EBC rotor would be my choice , certainly over mounting a second disc, in which I don't believe, the more after a member wrote recently he immediately took it off, unhappy with the extra unsprung weight.
http://forums.sohc4.net/index.php?topic=64964.msg712087#msg712087

If you thin then down and reduce the OD the additional weight is minimal. The problem with 1 rotor is the strong twisting force it applies to the front end during hard braking. The twin rotor system eliminates most of that.

[MCRider]

the EBC rotors are stainless steel, so no rust

http://www.ebcbrakes.com/motorcycle_brake/pro-lite_replacement_rotor/index.shtml

They may rust a little, but that's OK. The rotors on my FJR are stainless and they rust. Its just less stainless than ones that don't rust.

Cast iron discs rust like crazy and provide the best stopping. I think less stainless is better for braking.

[MCRider]

That EBC rotor would be my choice , certainly over mounting a second disc, in which I don't believe, the more after a member wrote recently he immediately took it off, unhappy with the extra unsprung weight.
http://forums.sohc4.net/index.php?topic=64964.msg712087#msg712087

If you thin then down and reduce the OD the additional weight is minimal. The problem with 1 rotor is the strong twisting force it applies to the front end during hard braking. The twin rotor system eliminates most of that.

Of course thinning is relative. The older Ks had pretty thick discs and could stand a lot of thinning. The later Fs are pretty thin to begin with so adding a disc is still twice.

Granted on the twisting. But a good fork brace takes a lot of that out. In my case I'm building for my riding style (fast backroads) which is to stay off the brakes and be as smooth as possible.

While this doesn't apply to our spindly 35mm forks, my HawkGT has 45mm forks and 1 brake and there is no twisting even without the brace, which i have. Just an info blurb.

[MRieck]

the EBC rotors are stainless steel, so no rust

http://www.ebcbrakes.com/motorcycle_brake/pro-lite_replacement_rotor/index.shtml

They may rust a little, but that's OK. The rotors on my FJR are stainless and they rust. Its just less stainless than ones that don't rust.

Cast iron discs rust like crazy and provide the best stopping. I think less stainless is better for braking.

Ive watched rust form on some Brembo rotors I have while sitting in a restaurant during a rain storm.

[wannabridin]

touche about the stainless.  must just have a the approaching lower limits of chrome, probably like 10.5-11%...  and when you brake, especially if there's gouges in the rotor, you increase the surface area quite a bit, exposing more to potential rust.

MC, are you sure that it wasn't just pieces of the brake pad that were rusting?  i know brake pads have steel in them, and if it's powderized, then it'll rust... 

[MCRider]

touche about the stainless.  must just have a the approaching lower limits of chrome, probably like 10.5-11%...  and when you brake, especially if there's gouges in the rotor, you increase the surface area quite a bit, exposing more to potential rust.

MC, are you sure that it wasn't just pieces of the brake pad that were rusting?  i know brake pads have steel in them, and if it's powderized, then it'll rust... 

I can't say for absolute sure that its not brake pad residue. But from what i know, I would bet money its a lower level stainless which allows rusting after a long time sitting, which mine has done lately. If I rode it regularly, the braking action would clear the rust.

Since the best braking comes from cast iron, no stainless at all, the manufacturers are looking for a compromise level of stainless which will look decent and provide good braking.

Earlier rotors like our CBs have too much stainless, so EBC can easily provide a better rotor with a more modern blend of less stainless.

[wannabridin]

good to know there.  thanks Ron

[754]

I cant help but wonder out loud if the Double Foating brake, is a plus or a minus. Should be able to fab up an Aluminum rigid mount for caliper to save weight, but setup would be crucial as nearly every floating rotor uses twin piston calipers..