Cellphone Camera Reveals eBike "just right for you"

Mike leroy

Active Member
A doctor takes your temperature to judge your health. Thermal images taken from a cellphone are like thermometers in homes, cars or a doctor's office. Judge motor power, battery capacity and brake size that best matches your particular environment and purposes from thermal images. Like Goldilocks said, "this one is much too hot, this one is too cold, but this one is just right".

A heart rate monitor can control the Impulse 2 bike motor on a Kahlkoff eBike. Your pulse rate and motor RPM can be surprisingly similar! The bike computer pulses battery power to the motor, rather than blood. Equating motor temperature with your heart rate should give you some idea of how hard to push the bike motor. The primary concept is a thermal image is color-coded for temperature to indicate the electrical effort.

The automobile industry has a long-standing history of using "Star Plots" to visually diagram differences between cars. Suppose we rate aspects of a bike ride on a scale from 1 to 5. We can also include personal information, i.e., our Heart Rate.

Star plots diagram the "big picture" or holistic viewpoint. We use bike "Heat" or temperature from the thermal image to judge the outcome of all the combined factors of the ride.

The following Star Plot illustrates a typical ride. All bike considerations are rated a "3", on a scale from 1 to 5. We also score our personal information , i.e., Heart Rate, as a "3", or average.

The following Star Plot tries to convey an under-powered bike because the outcome, Heat, has the highest score of "5". The bike was overheated.

If we scored Heat as too cold, "1", for another bike, then that motor is over-powered. The potential power was never utilized, so we overpaid for the bike.

To evaluate the bike from a holistic viewpoint, we considered the outside temperature, bike speed, additional weight, steepness, etc.... You can compare anything relevant to your particular situation.

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As you may have gathered, you could rely on your sense of touch to estimate temperature, on a scale from 1 to 5. A thermal image is exact. Certain motors have a tendency to overheat suddenly. In this case, thermal images are necessary. You will need a thermometer to calibrate your sense of touch with 140F, the optimal temperature.

Matthew McConaughey epitomizes my feelings in a YouTube car commercial.

Optimize and protect the bike electrical system from damage. Collaborate with riders in your www.NextDoor.com neighborhood to gradually increase electrical demands, until a particular eBike reaches the point of diminishing returns. In other words, the situation when an eBike is too hot -- can be CALIBRATED by all riders in a neighborhood. eBikes that remain too cold are overkill. A major reason for heat is the copper wires both inside the motor and connecting to the battery through the computer. Relate copper wires to veins in the human body.

My goal is to carry 50 pounds of food from the store. I might add ten pounds on each trip until I find the heat limit. I might need to add air pressure at the gas station on the return trip, due to a 30% increase in total weight. Asking a Nextdoor.com neighbor resolves uncertainty, doubt and hassle. Finding the best set of tradeoffs has costs in terms of "time and materials".

I started a www.NextDoor.com group called "Neighborhood Electric Vehicles". The NEV group aim is to collect local requirements and limits for a very specific area. A star plot is a good way to visualize tradeoffs. I believe my Nextdoor.com neighborhood is about a one mile radius.

Tools like this make great products go "viral" on the Internet. In other words, an early adopter struggles to customize a solution that genuinely improves his/her circumstances. Neighbors take notice and follow suit. Sometimes the stumbling block to gathering "critical mass" is the "chicken-or-egg" dilemma.

What pattern becomes apparent in the following map? Did you notice statistical "clustering"(i.e., two or more green parcel lots)? Clustering is the result of adjacent neighbors cooperating. Isolation (i.e., large pink gaps) is the opposite of clustering. The map leaves no doubt concerning the neighbors on the same [web] page!

A local expert must establish a viable, enduring solution for a particular purpose. A bike owner is perceived with more credibility than a dealer. Otherwise, you exit the market like Best Buy due to a 30% product return rate. A "shotgun" approach is probably less appropriate than a "rifle". EBikes are very powerful, special purpose tools that seem to reflect the rider's personality.

The speed of information flow is astounding. I smelled cigar smoke coming from the bushes in a park at 8am. Within one hour, a house across the street was robbed. By the end of the day, I was able to make the connection about the lurking thief using NextDoor.com.

Most people are struck by the higher eBikes speed. Fewer people realize an electric motor powers the faster bike. Posting questions to neighbors resolves the mystery in a less daunting and more hospitable manner.

The beach tires were the conspicuous difference I noticed on the first eBike I encountered. I asked the owner about the tires, oblivious to the battery and motor. The big impression the bike left on me was how effortlessly the eBike passed by all the traditional bikes. I know he would let me try his bike, which I greatly prefer over going to a retail shop.

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A FLIR thermal lens attached to your cell phone camera depicts "waste heat". Waste heat is energy taken from the battery that does not add power to the wheels. Waste heat indicates whether the eBike matches your needs.

A laser thermometer is less expensive and a more special purpose device. Mounting the laser on your handlebars provides realtime temperature of controller, brakes, battery or motor, just like the dashboard in a car.


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For example, the eBike in the above picture, has a glowing hotspot, centered around the rear axle.



Contrast the eBike picture with the bicycle and motorcycle pictures. Please note the wheel colors are a mirror image of each other. The bicycle hub is colored like the tire. You may notice the purple bicycle water bottle is close to room temperature.

Motorcycles and bicycles have stood the test of time.

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You could simply take thermal images of demo or rental ebikes to determine most appropriate for your situation. Please see the attached example map for an idea how to test bikes in a systematic manner, based on science. The idea is to take thermal images at specific energy consumption levels to compare bikes in an unbiased and meaningful manner. The basis for comparison is:

http://www.rohloff.de

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My guess is bicycles and ebikes are designed to 30mph standards, because it corresponds with USA tire standards. Downhill coasting speed for a 5% grade is 30mph. General standards may not apply to your specific situation. For example, the 5% grade is the lowest standard in the above table. My guess is eBikes provide the greatest hill-climbing benefit on hills between 5% and 10% grade.

Olympic ski jumps are about 80% grade. A USA flight of stairs is generally about a 65% grade. The maximum USA wheelchair ramp legal limit is 8%, which is the angle cars start to bottom out. An 8% grade takes eight times more physical energy than a flat surface.

My neighborhood is best represented by the 10% to 20% grade cases. From my experience and calculations, a 10% grade is the borderline when running/walking is the no slower than pedaling a bike. In fact, I usually outrun the few serious cyclists who attempt the hills in my neighborhood. Since the geology is an extinct volcano, an 18% grade falls in my primary route.

Bicycles are demystified when one realizes bicycles are gyroscopes. Bicycle "wobble speed" is 9mph, and is my minimum uphill speed requirement. Below 2.5mph a bicycle cannot balance and topples over like a spinning top. Bikers characteristically stand up and exaggerate lateral movements at wobble speed, with each turn of the crank arm, in an unrhythmic cadence. Like Palm trees swaying in wind gusts. A great deal of precious energy is lost in lateral movements by pushing full body weight down upon the pedals. Riders are often distracted with balancing the bike.

Runners can generate higher RPMs and direct all leg/foot power vertically up the hill. I train with an iPod metronome set to 80-100 beats/minute. A runner's lowest gear lies in his ankles, by fully extending the foot. Pedestrians gawk, smile, or chuckle when they see me catch and pass a bicyclist. Today, I raced a woman up a 7% grade. I started from a stop, while she was pedalling at about 5 mph. I blasted past her at 9 mph. She lagged far behind at the top. We both had a good laugh and exchanged comradeship by high-fiving.

Runners have an advantage over bicyclists above 15% grade, but comparisons are hard to draw. I have often beat bicyclists by several minutes up to skyline on the Archery Fire Trail in a huddart park. The comparison is indirect, because they must climb the hairpins on a kings mountain road. Kings mountain road is deadly and I do not even drive on it. I have seen over 100 near-miss collisions or accidents between bicyclists, deer and vehicles. A hike down into the steep gulches reveals all sorts of frightening accidents.

eBikes have a golden opportunity to shine above 10% grades, traveling above wobble speed (9mph). However, this steepness requires some tweaking with gear ratios and wheel size. Twenty-four to twenty-six inch wheels facilitate hill-climbing. A 400% gear ratio should suffice. A 300% gear ratio is typical for many bicycles. Higher gear ratios push bikes into more traditional vehicle gearbox territory, oil-filled integrated rear hubs.

The sweet spot, in terms of cost-to-benefit ratio, is traveling above wobble speed in 5% to 15% grades. A 15% grade is 15 times more effort than the same effort on flat ground.

My rule-of-thumb is 5NM per grade percent. In other words, 70NM may travel at wobble speed(10mph) on a 12% grade for 275 total weight, as a very general estimate.

Are weight-sensing racks missing from the controllers torque equation? Without the ability to tweak climbing features, a general purpose eBike provides little or no benefit. Gravity is unfriendly towards additional loads, e.g., carrying 50 pounds of groceries. My goal is to replace my car with an eBike. As hard as I try, 50 pounds on a 10% grade forces me to keep my car, which I rarely drive. I can comfortably walk with 35 pounds or run with 10 pounds in an expensive, Mountain Smith fanny pack.

I understand some eBikes have acceleramoter or altimeters to sense incline angle. I am sure motor RPMs can be controlled to deliver higher torque by adding another sensor(s). More power in Watts may be unnecessary. Watts = Torque x RPM. Alternatively, Torque = Watts / RPM. The bike controller algorithm only needs to slow the motor down when climbing uphill with heavy loads.

In other words, a software update could provide customized torque settings.

The controller is like your cellphone. Be sure your controller can be updated. Bosch supports upgrades via the USB port from a retailer. How you upgrade an Internet purchase is unclear to me.

Much less expensive and faster than renting bikes is to ask other people to ride the route on the map. The most important action is to give your friend a FLIR lens for their cellphone. If they take thermal pictures at all the places indicated on the map, you can easily and fairly compare different bikes.

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BTW - if you follow this route, it will take you to beautiful Stulsaft park. Take the "Silverhill Mountain Lion" park warnings seriously. I came across a deer kill and SML tracks in the mud around Christmas. A deer was killed in a backyard in the past two weeks. I see at least a dozen deer each week. Many mountain lions live in this area. San Mateo county posts sightings on a regular basis for mountain lions.

I want an eBike for transportation first and recreation secondly. I run two miles to my local store for groceries and carry 10-35 pounds of food back. I need hill climbing power, which seriously overheats motors carrying loads, in 10-20% grades. More importantly, I need great brakes, because downhill coasting speed exceeds the 35mph speed limit. My estimates indicate 90NM of torque.

Racks that can support 50 pounds is still an unresolved issue. Racks that attach to seat posts have much lower weight limits. The most appropriate racks may need to be built into the frame. Ideally, I would like to distribute the weight evenly on both wheels. I do not know if this is possible with a full suspension mountain bike..

I am going to draw the line at 48V systems. I need 750 to 1kW. I have not found an appropriate solution from the major bike manufacturers. I plan to buy a new mountain bike and install an 8Fun/Bafang BBS02 750W drive.

The HPC Supermundo may be a great choice! Based on Urban Commuter M-Drive designed for the HPC Supermondo, Yuba Mundo, Xtracycle Edgerunner, and Surly Big Dummy.

I am reluctant to do so because there is no cost savings. I also prefer buying from a company that will service the bike over the next five years. I will try to pedal without a motor to a store further away, with gentler hills. I can run up a 7% grade above ten mph. I have no idea how running translates to biking. I will give training a few months, perhaps I can manage without a motor by tweaking the gear ratios.

In case of emergency or inconvenience, the bus bike rack is my fallback. So, the frame must be diamond shaped. I favor a mountain bike for safety reasons. The Schwable ProCore tire tubes have two air chambers, which gives better emergency control. The additional weight increases the risk of a flat tire. The ProCore system basically consists of two inner tubes. The YouTube video shows racers running the tires flat.

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I can wait another year, because I am a runner, not a cyclist. I am encouraged by the rapid advances.

The BMW Evolution C electric scooter is a better option for me now, but BMW North America is not importing them.

A thermal image may answer some of the following questions concerning energy efficiency and safety:
  1. Which bikes make best use of expensive batteries?
  2. How to visually gauge the efficiency of your eBike on hills and at different speeds.
  3. Best brake size regarding stopping distance, for your conditions and motor type.
  4. How an oil cooled rear hub affects stopping distance, e.g., Rohloff IGH.
  5. How much more waste heat does a hub (e.g., Outrunner) motor produce compared to a center-mounted (e.g., Inrunner) motor ?
  6. What affect does a through-axle have on hub temperature?
  7. How to optimize the financial investment in your electrically powered SYSTEM, I.e., how to minimize wear-and-tear.
  8. When does a 26" wheel perform better than a 29" wheel, based on specific purposes, e.g., hill climbing torque vs. Flat ground high speed?
  9. When does tire tread or air pressure have a significant affect upon performance?
  10. Does your environment and purposes require special copper wiring in the motor (I.e., motor velocity constant).
  11. How should the motor attach to the frame to shed most heat through the frame (I.e., functions as a radiator) ?

Mike
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Mike leroy

Active Member
Thermal image of FET controller for a go-kart. I often wonder about the Controller, because it connects the battery to the motor. The wires can be a thin gauge and may present a weak link in the system. FETs have caused overheating.

http://www.etotheipiplusone.net/?p=3096
 

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calvin

Active Member
Ahem, where to start? Let's see....
  1. How much heat is transferred to the rear axle by the chain from the center-mounted motor? Answer: None.
  2. Does the rear axle, hub, spokes and rim function like a radiator for hub motors? Answer: No.
  3. Can tires become over-heated or unsafe, if the wheel functions like a radiator? Answer: The wheel does not function as a radiator.
  4. Does a belt driven bike conserve battery power or lower motor temperature? Answer: No.... Can't answer any more questions because my kernel panicked.
 
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Mike leroy

Active Member
Ahem, where to start? Let's see....
  1. How much heat is transferred to the rear axle by the chain from the center-mounted motor? Answer: None.
  2. Does the rear axle, hub, spokes and rim function like a radiator for hub motors? Answer: No.
  3. Can tires become over-heated or unsafe, if the wheel functions like a radiator? Answer: The wheel does not function as a radiator.
  4. Does a belt driven bike conserve battery power or lower motor temperature? Answer: No.... Can't answer any more questions my kernel panicked.
Calvin,

What is the model for heat dissipation ?
What accounts for the difference is tire temperature ?
 

Mike leroy

Active Member
Ahem, where to start? Let's see....
  1. How much heat is transferred to the rear axle by the chain from the center-mounted motor? Answer: None.
  2. Does the rear axle, hub, spokes and rim function like a radiator for hub motors? Answer: No.
  3. Can tires become over-heated or unsafe, if the wheel functions like a radiator? Answer: The wheel does not function as a radiator.
  4. Does a belt driven bike conserve battery power or lower motor temperature? Answer: No.... Can't answer any more questions my kernel panicked.

Calvin,

My intuition tells me the sweet spot for ebikes is between 5% to 10% grades as Neighborhood Electric Vehicles (NEVs). My interest is transportation, not recreation. EBikes make economic and emotional sense below 10% grades, as NEVs. My neighborhood exceeds 10% grades. I rarely see anyone pedal faster than 4mph. I easily outrun most bicyclists due to the steepness.

My intuition tells me an eBike will absolutely NOT work in my neighborhood. I am trying to reason that an eBike could work reliability on hot CAlifornia days in my neighborhood. Your answer resonates with my intuition, not reasoning.

Only 3 roads are available to me: a 10%, 15% and 20% grade. The 10% grade is usually very busy with commuting traffic, and only rarely viable. 70NM of torque may work on a 15% grade, but I have reservations about a 20% grade.

I ran to the store this morning on the 20% grade. I walked back with 30 (thirty) pounds of groceries on the 15% grade. The trip is 2 miles in each direction. The temperature was very cool this morning. I was drenched in sweat when I returned. It is safe to assume 200W of pedalling effort.

How would I calculate the Bosch motor temperature for this activity on an 80F day?

Your answer makes it very easy for me to abandon this exercise. my understanding is the optimal temperature for motors of this type is 140F. That only leaves 60F of electrical heat. I have read that people have cooled motors by 90F by filling the motor with oil.

How could an air-cooled engine generate less than 60F, pushing 250-275 pounds up a hill that averages a 10% grade, for 2 miles, at 10mph (wobble speed) ? I live on an extinct volcano. The slope increases with distance in a non-linear fashion.

My intuition tells me the motor will overheat or operate inefficiently without a cooling system. I would like to overcome my intuition with reason. But facts are difficult to find. I do not believe opinion. I would really like to believe it is possible to avoid overheating or inefficient operation of the motor on a hot day.

I am very comfortable with running.

Thank you,
Mike
 
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calvin

Active Member
Calvin,

What is the model for heat dissipation ?
What accounts for the difference is tire temperature ?

We don't need a theoretical model for heat dissipation... the empirical proof is in your thermal imagining, it indicates that the hub motor is glowing.... the heat from the windings moves by way of convection and IR radiation to the shell. Some people put oil in the motor to facilitate this heat transfer. Read through this long thread: http://endless-sphere.com/forums/viewtopic.php?f=2&t=48753 . Endless-sphere is the best place to go for answers to arcane or obscure questions. In this forum we are more focused on factory built bikes and their specifications, and equipment. ES is for minutia.
Notice in your imagery that the spokes are cool, so they can't be heating up the rear tire. The rear tire is hotter than the front because it receives more friction than the front due to its weight load and because it is the powered wheel. My ebike's rear wheel is more worn than the front because of these two facts.
BTW, When I first got my ebike, I was in a state of euphoria for a couple of weeks or more and was a bit over enthusiastic in my postings here. Court can attest to that.
 
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calvin

Active Member
Calvin,

My intuition tells me the sweet spot for ebikes is between 5% to 10% grades as Neighborhood Electric Vehicles (NEVs). My interest is transportation, not recreation. EBikes make economic and emotional sense below 10% grades, as NEVs. My neighborhood exceeds 10% grades. I rarely see anyone pedal faster than 4mph. I easily outrun most bicyclists due to the steepness.

My intuition tells me an eBike will absolutely NOT work in my neighborhood. I am trying to reason that an eBike could work reliability on hot CAlifornia days in my neighborhood. Your answer resonates with my intuition, not reasoning.

Only 3 roads are available to me: a 10%, 15% and 20% grade. The 10% grade is usually very busy with commuting traffic, and only rarely viable. 70NM of torque may work on a 15% grade, but I have reservations about a 20% grade.

I ran to the store this morning on the 20% grade. I walked back with 30 (thirty) pounds of groceries on the 15% grade. The trip is 2 miles in each direction. The temperature was very cool this morning. I was drenched in sweat when I returned. It is safe to assume 200W of pedalling effort.

How would I calculate the Bosch motor temperature for this activity on an 80F day?

Your answer makes it very easy for me to abandon this exercise. my understanding is the optimal temperature for motors of this type is 140F. That only leaves 60F of electrical heat. I have read that people have cooled motors by 90F by filling the motor with oil.

How could an air-cooled engine generate less than 60F, pushing 250-275 pounds up a hill that averages a 10% grade, for 2 miles, at 10mph (wobble speed) ? I live on an extinct volcano. The slope increases with distance in a non-linear fashion.

My intuition tells me the motor will overheat or operate inefficiently without a cooling system. I would like to overcome my intuition with reason. But facts are difficult to find. I do not believe opinion. I would really like to believe it is possible to avoid overheating or inefficient operation of the motor on a hot day.

I am very comfortable with running.

Thank you,
Mike

My bike has a 36 volt 500 watt motor that is pushed by a 15 amp hour battery, it suffices for the flats here in Phoenix. You will need at least a 48 volt system with a 500 watt, preferably 750 watt motor.... Get a least a 15 amp hour battery, then you've got a chance. Also, I know from personal experience, that riding your bike in the summer heat is going to damage the battery.. if I want to ride my bike this summer... I've got to get out of town!
 

Mike leroy

Active Member
Calvin,

Thank you. You have confirmed my intuitive guess.

I started a "Neighborhood Electric Vehicle" group on Nextdoor.com. I believe geographical areas vary too greatly, even within my town, to get appropriate advice.

I do not own any bike. I am considering buying an eBike. I trust an eBike solution exists, but it will take tedious tweaking and a great deal of research.

I look at my hills. My immediate reaction is an electric bike will not climb my primary road, an 18% grade. I do not want to give up without giving ebikes a fair chance. I love the eBike concept!

I wrote Bosch, Haibike, Felt and Focus the following:

Hi,

My road is an 18% grade for 275m (rises 50m). The next 1100m are a 7% grade, followed by 900m of 2% grade. I often carry 30+ pounds of food 2 miles from the store on my road in a fanny pack and backpack. The overall grade is 10%, on an extinct volcano.

I take this route 5+ days per week, partly on a park fire road. I am looking to replace my car with an eBike as a Neightborhood Electric Vehicle. My primary intent is to use the bike for transportation, not recreation.

I weigh 175 pounds and can run up the hill easily. I outrun most cyclists on a parallel road that is half as steep. I am drenched in sweat afterwards.

Can people in my physical condition pedal at 10mph with 50 pounds of groceries on your bike?

Let's assume my legs can generate 200W of power. if not, what is the most weight I could pedal at 10mph?

The rule-of-thumb I use is 5NM per percent grade for me to pedal 50 pounds of food uphill at 10mph. In other words, a 60NM torque will handle a 12% grade.

How hot would the motor get on an 80F day under these circumstances?
How likely is it for the motor overheat or become inefficient, assuming 140F is the optimal operating temperature?
Would this drain or damage the battery in an unusually fast manner at maximum assist?

Can I install front and rear racks on the bike? Which rack manufacturer would you recommend? Should I distribute the load evenly, I.e., 25 pounds on both racks?

I would probably replace the tires with a road tread, not knobby tires, although half of the trip is on metalled road surface. Which tires do you recommend that would work best with the Schwable ProCore tube?

What PSI do you recommend running Schwable ProCore on the bike?
Is a hard tail better with ProCore?

Do you recommend changing the rear cassette for better gear ratios? My area ranges from 10% to 20% grade.

Mike

PS: Using Rohloff gear display table to match grade percentage with gear ratios.

http://www.rohloff.de
 

Ann M.

Well-Known Member
Calvin,

My intuition tells me the sweet spot for ebikes is between 5% to 10% grades as Neighborhood Electric Vehicles (NEVs). My interest is transportation, not recreation. EBikes make economic and emotional sense below 10% grades, as NEVs. My neighborhood exceeds 10% grades. I rarely see anyone pedal faster than 4mph. I easily outrun most bicyclists due to the steepness.

My intuition tells me an eBike will absolutely NOT work in my neighborhood. I am trying to reason that an eBike could work reliability on hot CAlifornia days in my neighborhood. Your answer resonates with my intuition, not reasoning.

Only 3 roads are available to me: a 10%, 15% and 20% grade. The 10% grade is usually very busy with commuting traffic, and only rarely viable. 70NM of torque may work on a 15% grade, but I have reservations about a 20% grade.

I ran to the store this morning on the 20% grade. I walked back with 30 (thirty) pounds of groceries on the 15% grade. The trip is 2 miles in each direction. The temperature was very cool this morning. I was drenched in sweat when I returned. It is safe to assume 200W of pedalling effort.

How would I calculate the Bosch motor temperature for this activity on an 80F day?

Your answer makes it very easy for me to abandon this exercise. my understanding is the optimal temperature for motors of this type is 140F. That only leaves 60F of electrical heat. I have read that people have cooled motors by 90F by filling the motor with oil.

How could an air-cooled engine generate less than 60F, pushing 250-275 pounds up a hill that averages a 10% grade, for 2 miles, at 10mph (wobble speed) ? I live on an extinct volcano. The slope increases with distance in a non-linear fashion.

My intuition tells me the motor will overheat or operate inefficiently without a cooling system. I would like to overcome my intuition with reason. But facts are difficult to find. I do not believe opinion. I would really like to believe it is possible to avoid overheating or inefficient operation of the motor on a hot day.

I am very comfortable with running.

Thank you,
Mike
@Mike leroy , Aha! an old volcano; now its starting to make more sense. What everyone here has tried to do was determine how to help you get up a 10%+ grade..., and there are a number of solutions, non standard, beyond the 750watt /48V configuration. The thermal images are only valid for the specific time/temp/place they are shot, not a general evaluation unless you are comparing them to a specific benchmark and I don't see that here. They are a handy diagnostic tool--we use one in the shop when faced with odd electrical issues of one sort or another. Motors/controllers & wiring harnesses will show heat dissipation; its intrinsic to running an electric system and not necessarily a reason to ditch a product. Electric Rider and Golden Motor and others have a history with high voltage motors & battery systems. Electric Rider imports some decent product and has a good reputation for solutions for custom electric vehicles that need unusually high torque or high speed. Call them up, they're here in the US, real people pick up the phone, or email them; they're great on the communication.. They've designed motor systems for odd heavy items that have to climb steep hills like a 500lb, 3 wheel Tuktuk that's going to carry 250-300lbs of person on top of the bike's weight.

With regards to overheating in higher temps & humidity; there's no perfect answer right now. You know the battery/motor/controller manufacturers would be ecstatic if one product answered 100% of the needs; no one is there right now, but that does not make what is available less valuable. Heating & cooling issues are very dependent upon the ambient temperature and humidity, thus no one solution. In addition, the motor wattage & battery voltage configuration will also affect heat generation. Some electric motorcycle manufacturers, like Brammo, use water cooled systems as a solution to the heat issue. Why don't you take the wealth of skills you possess and tackle the issue with an electric vehicle group--design the cooling system you need; this would benefit electric vehicles in general.

BTW, please use the thumbnail image size for pictures.
 

Mike leroy

Active Member
Ann,

I went to great pains to create a benchmark map. Please see the attached map.

The FLIR lens serves as a calibration tool, not a diagnostic tool, in my case.

The rapid technological advances encourages me to wait until an established company offers an eBike that meets my needs. I have waited one year, already. I am patient. Battery technology lags behind motor technology.

My intent is to understand and judge existing class 1 bikes with an FLIR lens. I want low-end torque, not high speeds. The 48V, 350+ Watt, 60+ NM TORQUE motors are orientated at 28mph Class 2 speed pedelecs. I really am not looking for a moped or motorcycle.

My preference is to leave the power assist at the lowest level. My challenge is getting up the 18% grade with 50 pounds of food at wobble speed(10mph), in 80F temps.

My conjecture is a FLIR cellphone lens can help optimize and avoid damaging the bike electrical system. You and riders in your www.NextDoor.com neighborhood gradually increase the electrical demands, until a particular eBike reaches the point of diminishing returns. In other words, the situation when an eBike is too hot -- can be CALIBRATED by ALL riders in YOUR neighborhood.

I started a www.NextDoor.com group called "Neighborhood Electric Vehicles". The NEV group aim is to collect local requirements and limits for a very specific area. I believe my Nextdoor.com neighborhood is about a one mile radius.

Tools like this make great products go "viral" on the Internet. In other words, an early adopter struggles to customize a solution that genuinely improves his/her circumstances. Neighbors take notice and follow suit. Sometimes the stumbling block to gathering "critical mass" is the "chicken-or-egg" dilemma.

What pattern do you see in the following map? Did you notice statistical "clustering"(i.e., two or more green parcel lots)? Clustering is the result of adjacent neighbors cooperating. Isolation(i.e., large pink gaps) is the opposite of clustering. The map leaves no doubt concerning which neighbors are on the same [web] page!

A local expert has to establish a viable, enduring solution for a particular purpose. A bike owner is perceived with more credibility than a dealer. Otherwise, you exit the market like Best Buy due to a 30% product return rate. A "shotgun" approach is probably less appropriate than a "rifle". EBikes are very powerful, special purpose tools that seem to reflect the rider's personality.

A local expert has to establish a viable, enduring solution for a particular purpose. Otherwise, you exit the market like Best Buy due to a 30% product return rate. A "shotgun" approach is probably less appropriate than a "rifle". EBikes are very powerful, special purpose tools that seem to reflect the rider's personality.


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Ann M.

Well-Known Member
Ann,

I went to great pains to create a benchmark map. Please see the attached map.

The FLIR lens serves as a calibration tool, not a diagnostic tool, in my case.

The rapid technological advances encourages me to wait until an established company offers an eBike that meets my needs. I have waited one year, already. I am patient. Battery technology lags behind motor technology.

My intent is to understand and judge existing class 1 bikes with an FLIR lens. I want low-end torque, not high speeds. The 48V, 350+ Watt, 60+ NM TORQUE motors are orientated at 28mph Class 2 speed pedelecs. I really am not looking for a moped or motorcycle.

My preference is to leave the power assist at the lowest level. My challenge is getting up the 18% grade with 50 pounds of food at wobble speed(10mph), in 80F temps.
I understand; your situation is an extreme. Sometimes real innovation comes from conquering the challenges of the extreme. More than a few times we've seen great product come in for repair or permanently damaged after the owner repeatedly pushed the item way beyond what it was spec'd for. To me, that seems like a great waste of $$ and material.
 

Mike leroy

Active Member
Ann,
I am trying to provide a way for people to gather their experience, so usage is within reasonable tolerances. Everyone wins.

I have broken racing skis in half and cracked the steel binding toe plate from jumping off cliffs. Nobody is happy when products are abused. The best we can do is collaborate, rather than venturing into undefined territory.