Cost-Benefit Comparison: Brakes for Fast Electric Bikes

Mike leroy

Active Member
Are you interested in 35mph uphill speeds? How about the downhill trip? Coasting speeds on my hill easily exceed 50 to 60 mph. What do you need to know to make braking at high-speeds as safe as braking at low speeds? How much reaction time and distance actually exists when a car turns into your lane? What Anti-lock Braking Systems (ABS) equivalent is available for bikes?

The punishment downhill racers exert on their brakes inspires confidence.


This is my neighborhood -- only 14 miles of one road. How do accidents in your area compare?

http://almanacnews.com/news/2013/11/22/the-troubled-beauty-of-skyline-boulevard

"According to California Highway Patrol accident records, between 2003 and 2012, there have been 205 accidents on Skyline Boulevard between Page Mill Road in Palo Alto and the northern edge of Woodside (roughly mileposts 3 and 17). About half those accidents have involved two-wheeled vehicles: bicycles in 18 of them and motorcycles in 92, with fatal injuries killing two bicyclists and eight motorcyclists.

With the odds permanently stacked against the bicycle in a collision, the best course is not to have one. Flashing daytime lights are a must, she says, a small investment with big safety returns in that the lights give motorists a clue."


I feel certain that eBikes will be banned from my neighborhood bike lanes. The only viable option is an electric bike over 750 watts that must be registered as "motorized cycle" with CA DMV and requires a CA M1 motorcycle license. Every local I have spoken with immediately concedes that fact due to the popularity, road conditions and exhausted road capacity. My local roads simply cannot accomodate electric bikes in the bike lane, because riders will be constantly passing conventional bikes on single lane roads. Some bike groups of one hundred or more conventional bicycles are a moving road block for electric bikes incapable of the 35mph speed limit.

I am convinced registering a 45mph electric bike with CA DMV as a motorcycle is my only viable, long-term option.
 
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I plan to buy a 4000 watt HPC Revolution, as depicted in the following picture. Either Magura MT5 quad piston or MT7.

(Link Removed - No Longer Exists)
The bike is capable of 45+ mph on flat land. My hill has coasting speeds in excess of 50mph. The speed limit is 35mph. What braking capacity do I need?

I thought I had identified all the major accident-prone areas on my road. I thought a stop sign where people make left-hand turns, going uphill was the greatest danger. While walking downhill, I noticed the FedEx truck turning left against the opposing downhill traffic is more dangerous than the stop sign. The reason is the FedEx truck had about 10mph of momentum. The FedEx driver cut off the downhill traffic. All the downhill cars in both lanes had to suddenly brake very hard to avoid hitting the slow truck. A driver turning left from the stop sign is very unlikely to run the stop sign.


MT5
Class adapted for use on cycles, motorcycle racing's proven 4-piston technology creates an absolute maximum of braking force. No matter how difficult the trail terrain, our 4-piston technology and novel new ergonomics in the brake lever give you a performance package which will fill you with confidence. The MT5 is also perfect for S-Pedelecs. The aluminium, two-finger brake levers are ergonomically perfect for your hands, allowing you to easily and accurately apply the braking power you need, even during long braking actions. Our use of Carbotecture® technology in the brake handle housing keeps the MT5's weight down to a minimum and provides optimal braking performance.

  • ergonomic, 2-finger, aluminium brake lever
  • Carbotecture® housing & handlebar clamp
  • adjustable lever reach All-in-one,
  • 4-piston brake calliper with banjo
  • magnetiXchange brake pistons for easy brake pad replacement
  • weight only 380 g
  • Compatible with all MAGURA Storm and Storm SL discs
Color: Polished Black Anodized
Warranty: 5-year leakproof guarantuee for brake levers and cylinders after providing the original proof of purchase.

Technology
Additional parts for your MAGURA product...
Weight ~380 g (with 160 mm Storm SL-Rotor)
Colour Black (Master), Black (Caliper)
Technical features Full hydraulic dual piston floating caliper
Hydraulic system Open, with expansion chamber
Intern. standard mounting (IS) Yes, adaptor
Pad wear adjustment Automatic
Postmount mounting (PM) only front Yes, direct mount
Disc diameter (mm) Front 203/8, 180/7, 160/6 Rear 203/8, 180/7, 160/6, 140/5 (ONLY Storm SL)
Centerlock compatible Yes, with adaptor
Transmission medium MAGURA Royal Blood mineral oil
Brake hose MAGURA disc tube easily shortened
Hose fitting caliper RHR - Rotateable house routing
Brake pads Organic 9.1 Performance (4 Pistons 2 Pads) 8.1 Performance (4 Pistons 4 Single Pads)
Material fitting bolts Steel
Brake lever and caliper Carbotecture SL (Master), Aluminium forged (Caliper)
Lever blade Aluminium
Reach adjust Yes
OPD (caliper in one-piece design) Yes
BAT (bite point adjuster) No
EBT (Easy Bleed Technology) Yes
2-Piece Lever Clamp Yes
Dual Docking for trigger shifters Yes
magnetiXchange Yes
Feel-Safety-Ergonomic Yes
Accessoires

Storm Rotor
Storm Rotor (Steel): appr. 10% lighter than predecessor, enhanced durability, high braking performance, optimized wear features, 203, 180,160 & 140mm discs available, IS 6-hole and centerlock compatible with new centerlock adaptor.

ADAPTORS FOR ALL DISC BRAKE MODELS ›››
ShiftMix E
fits with SRAM-Trigger shifters


MT7
The MT7 stands for maximum braking performance and stability in extreme conditions. In the tough, bike-testing worlds of Enduro and Downhill, the additional braking power of the 4 brake pistons is a positive safety factor. The aluminium, two-finger brake lever - with toolless adjustment - and the adjustable bite point provide the necessary ergonomics for perfect brake control, even in difficult terrain and on long downhill runs.

  • Carbotecture® SL brake lever housing and aluminium handlebar clamp
  • Ergonomic, 2-fingerbrake lever
  • Toolless adjustment of lever reach and bite point
  • Forged 4-piston brake calliper with banjo
  • magnetiXchange brake pistons for easy brake pad replacement
  • weight only 375 g
  • Compatible with all MAGURA Storm and Storm SL discs
Color: Mystic Grey Anodized
Warranty: 5-year leakproof guarantuee for brake levers and cylinders after providing the original proof of purchase.

Technology
Weight ~375 g (including 160 mm Storm Rotor)
Colour Black-Fluro-Yellow (Master), Mystic Grey Anodized (Caliper)
Technical features Full hydraulic dual piston floating caliper
Hydraulic system Open, with expansion chamber
Intern. standard mounting (IS) Yes, adaptor
Pad wear adjustment Automatic
Postmount mounting (PM) only front Yes, direct mount
Disc diameter (mm) Front 203, 180, 160 Rear 203, 180, 160
Centerlock compatible Yes, with adaptor
Transmission medium MAGURA Royal Blood mineral oil
Brake hose MAGURA disc tube easily shortened
Hose fitting caliper RHR - Rotateable hose routing
Brake pads Organic 9.1 Performance (4 Pistons 2 Pads) 8.1 Performance (4 Pistons 4 Single Pads)
Material fitting bolts Aluminium
Brake lever and caliper Carbotecture SL (Master), Aluminium forged (caliper)
Lever blade Aluminium
Reach adjust Yes (tolless)
OPD (caliper in one-piece design) Yes
BAT (bite point adjuster) Yes (tolless)
EBT (Easy Bleed Technology) Yes
2-Piece Lever Clamp Yes
Dual Docking for trigger shifters No
magnetiXchange Yes
Feel-Safety-Ergonomic Yes
Accessoires

Storm Rotor
Storm Rotor (Steel): appr. 10% lighter than predecessor, enhanced durability, high braking performance, optimized wear features, 203, 180,160 & 140mm discs available, IS 6-hole and centerlock compatible with new centerlock adaptor.

ADAPTORS FOR ALL DISC BRAKE MODELS ›››

ShiftMix E
fits with SRAM-Trigger shifters
 
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I research and write articles in fits-and-starts, as my spare time permits. Writing an article usually takes one full week. So, check back regularly.
 
Just buy a scooter or motorcycle. No one is going to pedal an 80lb bike around. Just save some of the weight and lose the pedals. Seriously this is not an ebike by any means. Might be able to out run a hungry mountain lion, but I doubt it. Nice thing is the mountain lion will only eat the rider, lol.
 
Mike,

I'm just trying to have some fun posting and am excited about the new world if ebikes. With your "unique bike" comment, which I take that as a compliment, and I hope it was, since I don't think there are many DB ebikes out there yet or on this forum, I call an end to this. With that I pledge a flag of truce, never to post anything that you might feel is negative about your posts again. You are truly dedicated to that in which you believe and that is a good thing. The world needs more people dedicated to a cause for change to take place. In the mean time I'm going to "stalk" J.R., lol, and when I find him chastise him vehemently for getting involved in this, lol. I'm a big boy and can take care of my own affairs, so he will be severely reprimanded when I track him down, lol. Until then just enjoy life as I know you do.
 
Mike,

I'm just trying to have some fun posting and am excited about the new world if ebikes. With your "unique bike" comment, which I take that as a compliment, and I hope it was, since I don't think there are many DB ebikes out there yet or on this forum, I call an end to this. With that I pledge a flag of truce, never to post anything that you might feel is negative about your posts again. You are truly dedicated to that in which you believe and that is a good thing. The world needs more people dedicated to a cause for change to take place. In the mean time I'm going to "stalk" J.R., lol, and when I find him chastise him vehemently for getting involved in this, lol. I'm a big boy and can take care of my own affairs, so he will be severely reprimanded when I track him down, lol. Until then just enjoy life as I know you do.
I commend your approach. Forgiveness is easy and essential. I can let it go.

I am at the end of my research. I think I understand the technology to the point that it is no longer worthwhile to try to find other people to collaborate with.

My neighborhood is like swimming against a rip tide. Cars are king. Walking and running are the best "clean" and healthy ways around, as much as I hate to admit it.

I can make the technology work for me. I cannot change the unsafe road conditions.

Left hand turns in traffic makes the fast lane as dangerous as the slow lane. At first, I thought avoiding the right hand lane is the antidote. The more I study the fast lane, the less viable it seems. A FedEx truck making a left hand turn almost caused a pileup in both lanes this morning. The cars stopped about two feet before hitting the truck.

So, yes let it go. I wish it were also that easy to make the roads safe.
 
Yes, on this I can agree completely. Car/truck drivers are complete a - holes when it comes to bikers, and I am included in the list at times. Bikers are hard to pass and groups are even harder on roads with no bike lanes like most in Maryland, hills and turns, lots of them. There is a need for long range designated bike lanes in many states like in MD where we can feel to safely ride.

.
 
Yes, on this I can agree completely. Car/truck drivers are complete a - holes when it comes to bikers, and I am included in the list at times. Bikers are hard to pass and groups are even harder on roads with no bike lanes like most in Maryland, hills and turns, lots of them. There is a need for long range designated bike lanes in many states like in MD where we can feel to safely ride.

.
A Google VP, riding a bike, was killed by a FedEx truck. The left-hand turn is the culprit. I saw the same situation repeat itself on my street yesterday morning. The Google VP incident generated such media publicity that bike safety is now a major issue. The cops aggressively ticket bicyclists, too.

As soon as eBikes appear on my streets in numbers, they will be banned.

I can avoid the most dangerous road sections by riding a conventional mountain bike through the park fire roads. CA AB-1096 legislation makes a conventional bike the only viable alternative. 750 watts provides little benefit, at great cost, in my hills. The bus bike rack is a safer, faster and less expensive way to get up my hill, which has a 13% grade section. I hate to take the bus, but better than pedaling at 5mph. I run up the hill faster!

At least I now know which components to buy in a conventional mountain bike. I will probably spent more money on a mountain bike than a good 750W eBike would cost.

How ironic! CA AB-1096 eBike industry backers forced me to avoid buying an EBike. The legislation eliminated my only halfway decent eBike route. Ebikes are socially unaccepted in my area. The best strategy is to fly under the radar. But now that cover is blown. Foolish!
 
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Mike,

I'm just trying to have some fun posting and am excited about the new world if ebikes. With your "unique bike" comment, which I take that as a compliment, and I hope it was, since I don't think there are many DB ebikes out there yet or on this forum, I call an end to this. With that I pledge a flag of truce, never to post anything that you might feel is negative about your posts again. You are truly dedicated to that in which you believe and that is a good thing. The world needs more people dedicated to a cause for change to take place. In the mean time I'm going to "stalk" J.R., lol, and when I find him chastise him vehemently for getting involved in this, lol. I'm a big boy and can take care of my own affairs, so he will be severely reprimanded when I track him down, lol. Until then just enjoy life as I know you do.
and double Like.
 
The Magura hydraulic brakes on my Stromer are nigh on amazing. Lots of feel and control with a full pull that will put you on your head if you're not careful. The Stromer weighs 62-64lbs for comparison. Don't see a model # anywhere.
I would think the rotor would be a prime concern at those speeds. Gonna generate a lot of heat and warpage would likely be hard to avoid.
If I was going to go 45mph on the flats and 60(?) downhill, I'd just use motorcycle wheels and brakes. And frame. And suspension.
 
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