I have a request to the users that have disc brakes

[mateusleo]

Hello all!

So, if you have a disc brake on your e-bike, i have a resquest: please measure the size of the part that goes between the disc and the motor and post the model of the brake. If possible, pictures would be great!

The reason i'm asking this is because the space between the disc and the motor is very small, making us have a little options when choosing a disc brake. My clearance is about 14,3 mm... I'll post a picture below to make it clear.

 

[DAND214]

I have a Mac with 203 rotor and add spacers to get the clearance needed. Like you said 15mm before adding spacers. Don't really need the shimms to clear the motor with the 203 rotor but lined up better to the caliper to frame mount.
Using Shimano/Deore hydros.

Dan

 

[teklektik]

For Avid BB7 - here.

 

[mateusleo]

I have a Mac with 203 rotor and add spacers to get the clearance needed. Like you said 15mm before adding spacers. Don't really need the shimms to clear the motor with the 203 rotor but lined up better to the caliper to frame mount.
Using Shimano/Deore hydros.

Dan

I don't have strong reasons, but i want to keep the 160mm rotors. Also, i made a model with paper to compare the size od the rotor to the motor, the caliper would still stay on the tight clearance area but with its half out of it....

For Avid BB7 - here.

This one seems good...Is avid bb5 still smaller than bb7? Because money is very important on this discussion too ...

 

[teklektik]

This one seems good...Is avid bb5 still smaller than bb7? Because money is very important on this discussion too ...

Dunno - I use BB7s - great brake - very nice modulation with super easy adjust and pad replacement.
They are only about $50 for caliper, adapter mount, and 185 or 203 rotor from Price Point.

 

[mateusleo]

This one seems good...Is avid bb5 still smaller than bb7? Because money is very important on this discussion too ...

Dunno - I use BB7s - great brake - very nice modulation with super easy adjust and pad replacement.
They are only about $50 for caliper, adapter mount, and 185 or 203 rotor from Price Point.

Thanks for the info, but, i checked this site and shipping to Brazil costs 54 bucks hahahahaha. I'll check on ebay to see what i can find =)

 

[Ypedal]

hayes MX2 have a fairly thin profile, works on my 4 series clyte.. cable operated.

if you have a thread on disk adapter going on, add a freewheel shim to make up the needed space.

 

[mateusleo]

hayes MX2 have a fairly thin profile, works on my 4 series clyte.. cable operated.

if you have a thread on disk adapter going on, add a freewheel shim to make up the needed space.

I don't think the frame would handle to be stretched even more, its already pretty opened and i dont want to make it complicated... I'm thinking about the avid bb7, it seems to fit. I would like if someone has it to measure the size and tell me, so i think what i should do, maybe some thin spacers...

 

[Ypedal]

i meant adding a shim between the disk adapter and the hub, to distance the rotor a few more mm's.. no frame stretching involved.

 

[SNOOT]

I have a magic pie 3 and hydraulic brakes. I had to machine material off the back of the caliper to make it fit.

 

[mateusleo]

i meant adding a shim between the disk adapter and the hub, to distance the rotor a few more mm's.. no frame stretching involved.

This is a simple solution, on the reach of my skills haha. I'll probably do it

I have a magic pie 3 and hydraulic brakes. I had to machine material off the back of the caliper to make it fit.

See that you created the account and your first post was a reply to me makes me glad haha. I don't have the skills or the material to machine the back off, also i'm afrait to damage it. I need a simple solution, like spacers, and this will probably be the solution. Just hope someone can tell me the size of the bb7...

 

[Chalo]

Is avid bb5 still smaller than bb7? Because money is very important on this discussion too ...

Even if BB7 is twice the cost of BB5, it is ten times the brake. BB5 sucks, to be frank.

Any mechanical brake with a back side adjusting dial (like BB7 or BB5) is thicker than necessary on the critical side. getting one without an adjuster on the fixed side may mean having to adjust the caliper position more often, but it will afford more clearance for a hub motor.

Allow me to reiterate that rim brakes have no such clearance problems with hub motors. They typically cost less, weigh less, and can work better too.

 

[biohazardman]

I also did the 203 mm Rotor on my single sided Hayes MX4 cable pull set up to get clearance and to improve braking as my bike is now faster and heavier than stock so I wanted to improve the brakes for safety reasons. Made life much easier on the brake install and the brakes are so good I did not even bother to use the hydraulics I bought. If you really have to keep the 160 rotors and need only a MM or so to clear the motor you could just file that off of the outside, circled area, of your caliper assembly right at the bolt area, where it installs to the bracket, that will bring the caliper assembly out if you have clearance to do so. Then just washer out the rotor out the same amount. This is probly fine if you do not need to much space. Lay the file on the bench and hold the caliper while filing it to keep things flat. Lots of ways of doing things.

 

[stinkler]

I had the same setup. had to run the adapter spacer and washers in between the disc and the adapter or my hayes 9 caliper would rub.

 

[deffx]

Edit...off topic...no useful information

 

[teklektik]

I need a simple solution, like spacers, and this will probably be the solution. Just hope someone can tell me the size of the bb7...

I gave the rotor-to-hub clearance measurement above.... Exactly what measurement are your looking for?

The BB7s use the Avid CTS mounting system which self-aligns when adjusting. You can simply file the outer adapter face to move the caliper outward and stick in a disc brake shim to move the rotor out a similar amount. Shims are readily available or cut down an old rotor. The CTS alignment magic will take care of any lack of parallel faces or generally poor filing on your part - no need to machine and no need to modify the caliper itself.

 

[mateusleo]

I need a simple solution, like spacers, and this will probably be the solution. Just hope someone can tell me the size of the bb7...

I gave the rotor-to-hub clearance measurement above.... Exactly what measurement are your looking for?

The BB7s use the Avid CTS mounting system which self-aligns when adjusting. You can simply file the outer adapter face to move the caliper outward and stick in a disc brake shim to move the rotor out a similar amount. Shims are readily available or cut down an old rotor. The CTS alignment magic will take care of any lack of parallel faces or generally poor filing on your part - no need to machine and no need to modify the caliper itself.

I also did the 203 mm Rotor on my single sided Hayes MX4 cable pull set up to get clearance and to improve braking as my bike is now faster and heavier than stock so I wanted to improve the brakes for safety reasons. Made life much easier on the brake install and the brakes are so good I did not even bother to use the hydraulics I bought. If you really have to keep the 160 rotors and need only a MM or so to clear the motor you could just file that off of the outside, circled area, of your caliper assembly right at the bolt area, where it installs to the bracket, that will bring the caliper assembly out if you have clearance to do so. Then just washer out the rotor out the same amount. This is probly fine if you do not need to much space. Lay the file on the bench and hold the caliper while filing it to keep things flat. Lots of ways of doing things.

That's what I'm going to do, seems to be the most simple solution. I'll buy BB7 as soon as I get money. Thank you guys.

 

[mateusleo]

Hey guys, i found this brake that seems to be a copy of avid bb7: http://dx.com/p/dongying-dual-side-adjustable-bicycle-rear-disc-brake-white-red-black-222077


I actually think it must use bb5 or bb7 pads, and they corst 1/4 of what bb7s cost,and its a good choice since i'm planning, if possible, to buy only one caliper, which is hard to find on ebay, the whole set costs alot more. What do you guys think about this brake?

 

[biohazardman]

Pics look good but hard to say about the inner workings of the unit. Having only one review doesn't help much either. BB7s are nice and have excellent reviews but I still run my stock single sided Hayes MX4 calipers and am very pleased with them even though an entry level disk system. I do need to make adjustments so they wear even, now and then, other than that I have not a complaint. You will need spacers for your calipers if you go larger than your stock size rotor. Lots of parts out there so I wish you good hunting.

 

[Supertux1]

I'll vouch for the BB7. On a MAC 10T motor, mine still required the spacer under the disc (moves it closer to the frame) and then a washer on the axle, (moves it away from the frame.) A little bit of grinding on the inner screw head as well. This is a 160mm rotor. I am thinking about converting this to a 203mm brake where I think it might clear the motor without any spacers or grinding at all, as well as providing better braking.

 

[cal3thousand]

Big issue for these, in my book, is chainstay spacing. If you have enough room to fit a disc without hitting the chainstay, add spacers as necessary and use a large disc if that gives clearance of the hub diameter.

On my bike with 150mm dropouts, I put 4mm of spacers under a 203mm rotor and the caliper now has PLENTY of room. And it was a somewhat poorly shaped/designed bit as shape and fit goes.

 

[athletic91]

I had to add 4mm of spacers to the left axle to get the disc to clear the frame. Thankfully my cute100 is small or else the calliper would have made contact

 

[mateusleo]

I had to add 4mm of spacers to the left axle to get the disc to clear the frame. Thankfully my cute100 is small or else the calliper would have made contact

Yeah, u'r right... Shimano hydraulic brakes have the piston between the rotor and the wheel, which makes them a little bit fat in this are...

 

[mateusleo]

My avid bb7 dic brakes and hs1 rotors arrived sometime ago. I installed the front disc myself, since it had nothing to be modified to make it fit, but the rear brake had some custom needs, so i waited till the mechanic has some free time and he managed to make the mods. After using bb7's for the first time it seemed like i had no brake before. I have no words, the guy made an amazing job, the back part of the brake had to be machined a little bit and some washers needed to be added between the rotor and the morot to make bigger clearance to the caliper. I just told him what i planned to do and he made a great job.

In the picture below you can see the washers:

The parts were very close to each other, but not touching:

The only problem was that the HS1 rotor i had didn't fit the motor, the mechanic said that the holes to the bolts didnt match, so i had to keep old rotor, which rubs against the pads because its oscillating allot, but eventhough its atleast 10x more braking power than previous SHIT brake. Also, its a lot easy to adjust the inside pad.

EDIT: Does anyone know where i can get info about this rotor with different holes? I mean to buy a new one since its not really good but i don't know how i can find any findo about it....

 

[biohazardman]

There might be some useful info here on another brake thread.

http://endless-sphere.com/forums/viewtopic.php?f=3&t=59665