Let's talk about brakes

If the skewer is loose or there is no "lawyer lip", I could imagine that the force of braking could tend to push a wheel out of the dropouts. (and have read a webpage somewhere about exactly that problem happening, where they suggested that calipers should be on the FRONT of the fork leg specifically to prevent this, as the rotational forces would push the wheel *into* the dropouts instead)

But if they're tight enough, it shouldn't happen.
 
Going 203mm in the front is a GREAT idea and I suggest it.

This was my 160mm front disc with about 25 miles one it from bicycle that could do 50mph, but was raced on a track.
hotdisc.jpg


Didn't notice any difference going 160mm to 203mm in flex between my small 20" susp fork which has much smaller tubes than my 26" fork I now run which is much larger.

I think 203mm in the rear isn't needed and would be more for looks due to the amount of weight shift that happens on braking... unless you are a cargo bike with lots of weight in the rear, then it's probably a good idea.
 
I have a QR front wheel as well and 250-260lb combined weight on a full suspension aluminum framed and forked ebike. Running the stock Hayes MX4 Mechanical disks with upgraded 203mm rotors, the style you see in the above pic, front and rear for over 5K now and they have been perfect. They stop me on a dime and I have been up on the front wheel, avoiding a van that turned in front of me, once. :shock: Stopped eight inches from his rear quarter panel with the rear of the bike in the air balanced a few seconds till it came down and continued on. I'm sure it looked good as I rode off. :roll: I check my skewers now and then to see that they are tight but it has not been a problem. Hard to say what someone's problem actually was but I am not the only one with this kind of set up and I have as yet not heard of anyone having the problem you describe. A few front motor horror stories though, ouch.
Just see that things are tight and stay that way to be safe.
 
I think the important thing is the ability to stop hard without lock up, and some brakes are much better than others at that.

I remember my experiences with car disk brakes, some would lock up or worse lock up one wheel. But that could have been the pads also, or both!

Some would even warp after a few thousand miles!

I'll report back when I swap disks and pads.
 
Ahhhh now that's more like it !!!

Where did you get those brakes and how did you mount on the other side of the fork ?

I can imagine the braking force with those!
 
I suppose that most ebike commuters have probably upgraded to disc brakes. One've my bikes has V-brakes...and the other, some Hayes MX-4 (mechanical) and the difference is quite noticeable. Especially on long downgrades, where the V-brakes seem to fade.
I just bought some very lightly used BB7's from ebay and can't wait to try them out. (replacing the V-brakes). What I am wondering is in the upgrade to front rotor that is 185 or 203mm....is there really a noticeable difference in such an upgrade?? My total bike weight plus mine is 290lbs. 15s4p w/9C rear.
For those who've made such an upgrade, could you guess at the (%) improvement in braking distance? Just in general, wanna hear about braking issues, etc. Thanks.
 
There is no improvement to braking distance with larger brakes. Your braking distance is determined entirly by your tires. any brake capable of locking up the wheel is capable of the minimum stopping distance.

But big brakes don't get as hot, shed their heat better, and let you modulate the pressure with better accuracy easier.

Avid makes a good 185 that works well with the BB7. Might want to use a Hayes rotor if you go with the 203.
 
Hayes are thicker spoked and stiffer with a higher surface area. Near-as-doesn't make any diffrence in 185mm and smaller, but I've heard people complain about "springyness" in Big Avids under hard braking.

Sort of old news now, but Avid makes better Mechanical Brakes, Hayes makes better rotors.
 
I dug out a 203mm rotor that's never been used. No name on it...has the clear etching for 203mm, and the only other etching says "S7", besides the rotational arrow, also deeply etched. Any clue as to maker? Guess I'll give er a whirl and see how it does. (It has lots of holes in it for cooling...some smaller and some larger..
Another thing...I've noticed that nearly everyone uses the larger rotor on the front if they go with different sizes. But it's also pretty apparent to me that the relative stopping power of the front brake (of identical make or size) is much stonger. Rear braking is barely noticeable on it's own. Wouldn't it then be slightly advantageous to use the larger rotor on the rears? (not for stronger stopping, as you mentioned above...but for more control on the modulation perhaps?)
Thanks for the Hayes rotor tip.
 
just finished my new disc install....put on the 160mm first and tried it out....then went immediately to the 203mm...and man...there's a quite noticeable difference. These are the BB7's. Didn't take long to adjust them to optimal.
I'm saving up for one for the rear too now (since I have a bob trailer on one've my setups...that pushes a bit harder (alot) down the hills). I'm working on brazing in V-brake mounts to the trailer and using one've those dual cable levers so I'll have all wheels with brakes. Wanna keep my batts in a slim, single-depth enclosure BENEATH the trailer. (scrapegaurds too...but this never goes offroad with batts, is the plan. It's because my frame on the Specialized FSR-XC is difficult to build an enclosure for.
Batteries forward are great...but batteries low are even better.
 
Brakes for cromotor 24s4p on phasor frame 24" wheel.

Need some stopping power to feel safe!!!! My top speed should be around 50mph.
I don't mind spending a few extra bucks to get good results. Though by all means if someone has a good cheap adequate solution please tell me.

Here are the brakes I'm leaning towards buying.
Avid code R, avid code is close to another $200
http://www.ebay.com/itm/NEW-2012-AV...Cycling_Parts_Accessories&hash=item2a1466f8d6
Or
Gatorbrake 8, I can get these for $429
http://www.ebay.com/itm/Gatorbrake-...Cycling_Parts_Accessories&hash=item565122685f

Any information would be much appreciated!
 
parajared said:
I have gotten away with 50mph and caliper brakes. It works ok... sorta. Disk brakes are one step better, and one step better yet is hydraulic disk brakes like the kind you see on motorbikes. Matt Schumaker is using hydraulic on his 50mph trike.
Click to expand...

Both above brakes are hydraulic. Gatorbrakes is pretty close to motorbike territory
Here is a thread on them http://endless-sphere.com/forums/viewtopic.php?f=3&t=24827
I'm using mechanical disc brakes on my current set up gone up to 46mph They work, kinda sorta, at those high speeds if I get cut off anything stopping me even a split second quicker might be the difference beetween a few scratches or a trip to the morgue :cry: Not trying to be to dramatic but yea.... Have to get better brakes on my current setup as well.
 
Avid BB7 with a 9 inch disk will be more brake than you will ever need for that bike.

If you really like Hydros, get the Avids, but there isn't any real point. Breaking power is a function of the tire. Any brake that can lock the wheel can give maximum power.

After try and comparing a lot of brakes, I went with Mecha Avid BB7s over any drippy brakes for my 50mph+ 120lbs Monster bike.
 
Regen braking along with the cheapest brake solution will provide good braking from high speed. Many controllers also have an eabs braking solution that is more powerful than regen braking if you want the strongest electric braking solution. It will take you to a dead stop without bike brakes. Either of these solutions are free assuming you have a controller that supports them.
 
Drunkskunk said:
Avid BB7 with a 9 inch disk will be more brake than you will ever need for that bike.

If you really like Hydros, get the Avids, but there isn't any real point. Breaking power is a function of the tire. Any brake that can lock the wheel can give maximum power.

After try and comparing a lot of brakes, I went with Mecha Avid BB7s over any drippy brakes for my 50mph+ 120lbs Monster bike.
Click to expand...

Thanks skunk,
What tires do you use?
 
wesnewell said:
Regen braking along with the cheapest brake solution will provide good braking from high speed. Many controllers also have an eabs braking solution that is more powerful than regen braking if you want the strongest electric braking solution. It will take you to a dead stop without bike brakes. Either of these solutions are free assuming you have a controller that supports them.
Click to expand...

I have regen now. What's eabs braking solution never heard of it?


What I like about hydraulic brakes is the apparent easy 2 finger pull and adjustment. Though the truth is I don't have enough experience on them. I've read lots of the for hydraulic, mechanical and even v brake arguments, seems like everyone just like what they like.....
 
Something a bit odd. Surly Larrys. 4" wide tire on 65mm wide rims running at 25lbs, so I have a lot of tread in contact with the road.

Thats not a recomendation for those tires at that speed. They get hot. But it takes a stout brake to skid that much tire in contact with the ground, and my BB7s do it fine. Then again, a quality hydro would do it fine too, but hydros don't add anything extra.

A lot of this is about feel. Some people like the super light feeling of drippy brakes. 1 finger stops instead of 2 finger stops, and fluid smooth feeling of the lever. Personaly I find the slight lag when releasing the brake as anoying as fingernails on a chalkboard, and I want the brake stiff enough that I can feel it's bite point through thick gloves.

BB7 also have pads available at almost every bike shop. Even walmart carries them.
 
I like what I'm reading about maguras price is definattely good, $200 front and rear though no rotors, if I get magura rotors its between $60 to $80 dollars depending on which I get plus adapters. This is another deal on avid r I just ran into.
Full package for $268 including rotors and adapters, very tempting.
http://www.ebay.com/itm/2012-AVID-C...Cycling_Parts_Accessories&hash=item20ca4cbf1f

Good hydraulic brakes comparison
http://www.bikeradar.com/mtb/fitness/article/how-we-test-hydraulic-disc-brakes-24345/

Seems like the magura mt2 and code r are pretty much on par performance wise. With the code r having a few little extras.
Price seems good.

Gatorbrakes, overkill huh, looks like I can get good performance for $150 less...
 
dimpirate said:
I have regen now. What's eabs braking solution never heard of it?
Click to expand...
Regen braking turns the motor into a generator and uses that as braking power, although it's really not the generator load slowing the bike. Once the motor/generator slows to a speed it can no longer generate enough energy to recharge the battery pack, you lose all it's braking power and the wheel freewheels at that point. That normally happens at 4-8mph, with the amount of braking power reducing as it approaches the slower speeds. EABS braking reverses current flow into the motor putting a reverse load on the motor, thus using small amounts of current rather than using the motor to generate current. It will bring your bike to a complete stop with a lot more braking power than regen braking. My controller has both, but I use regen braking because it provides plenty of braking power for me along with my normal brakes. But if you need lots of braking power, eabs braking will certainly give it to you. I've heard some people have called regen braking eabs braking in error, so make you need to know what you are really getting in a controller.
 
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