My Kona Smoke 29'er

[WonderProfessor]

I'm going to hate shelling out $100 for a pair of Schwalbe Supremes but I want them

-R

Good tires are worth every penny! For me, I would pay almost any amount to get bicycle tires that performed as well as steel-belted, radial automobile tires. When was the last time you had a flat tire while driving your car? I absolutely hate flats. They steal your time, your most precious commodity!

[Russell]

I decided to splurge and ordered a pair of Schwalbe Marathon Supremes (28x2.0, 700Cx50) to replace the Continental City Contact tires (700Cx47) since I couldn't find an exact replacement for the one blown tire. The Continentals with a perfectly smooth, hard 1cm center section may have rolled faster, I'm not sure, but the Supremes are wonderfully comfortable tires, they absorb shock far better than the Continentals and handle great too.

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I don't care too much for the reflective stripe on the sidewall so I darkened it with a Sharpie and close up it looks sort of purple but further away it's not real noticeable, it also still reflects light as you can see below in the non-flash Vs. flash pictures. I did prefer the look of the Continental's since their logo matched the yellowish Kona decals but whatcha gonna do.

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One other change I made to the bike in the search for comfort was adding a Cardiff Wessex leather saddle w/ springs. I ordered this before I received the Schwalbes because I didn't think the tires alone would offer as much improvement as they have. I'm not sure I care for the saddle however. I've only been on two rides with it and it's not broken in yet but I just can't get comfortable on it, nor can I keep up a good spin rate on it. I think like the original Kona saddle it's too wide for my bum. Oh well I can always sell it on eBay.

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-R

[WonderProfessor]

I've only been on two rides with it and it's not broken in yet but I just can't get comfortable on it ...

That's because the original design for upright bicycle seats was taken from various torture devices built in the Dark Ages.

For the life of me, I can not understand why recumbents are not more popular.

[adrian_sm]

For the life of me, I can not understand why recumbents are not more popular.

A friend of mine has a Lotus Elise. Beautiful car. But you have to be really defensive when driving it. Being so low tall vehicles don't see it, they see over the top of it.

I feel a bit the same about recumbents, the lower ride height would get me more nervous on the roads with cars. They have a hard enough time noticing a normal upright bike.

[GASSTINKS]

Those tires look great, as does the entire bike. When my pair of Marathon Plus wear out (I've got at least 2,000 miles on them currently without any flats), I'll try a pair of those 700x50 Supremes. Not sure if they would fit in my frame, though.

About upright bike vs. recumbent visibility: I've ridden both and can attest to the fact that you're just as INVISIBLE on an upright bike to drivers. HIgh-vis clothing, flashing led lights, and neon dummy flags help a bit, but not much. Most of the time I'm cut off by drivers it seems as if they are making a deliberate choice to ignore I'm in the bike lane beside them. Helps to have good brakes.

[WonderProfessor]

... about recumbents, the lower ride height would get me more nervous on the roads with cars. They have a hard enough time noticing a normal upright bike.

Sigh. Yet another myth propagated onward toward bicycling eternity ...

Recumbents are actually more visible than uprights. They are still odd enough that motorists notice them more than upright bikes. I can not tell you how many times motor vehicle operators have swerved towards me trying to get a better look. In the 1990's, drivers would pass me, stop their cars and get out to ask me about the bike. It is different now that recumbents are far more prevalent but they still are enough of an oddity to get themselves noticed. The low height is a red herring unless it is one of those very low trike recumbents where the rider is almost lying on his or her back. In this case, a large flag is warranted.

Disclaimer: The above does not apply when the motorist is either (1) driving with their eyes diverted to either [a] a mobile electronics device, [b] a newspaper or other reading material, [c] a porn flick displayed upon their illegally installed video monitor, or [d] the nearest sexually-explicit billboard advertisement. It also does not apply if they are (2) slapping their ill-behaved children, or (3) applying make-up, or (4) driving while under the influence of recreational pharmaceuticals, or (5) any number of numerous other tasks that motorists believe are far more important than the immediate task at hand, i.e. operating their motor vehicle.

Whether upright or recumbent, please be vigilant.

P.S. Recumbents are actually far more safer than uprights. You can not fly over the handlebars of a recumbent. The center of gravity is much lower and the weight is distributed more toward the rear wheel. Rather, you will fall sideways. A broken hip is far less deadly than a broken neck.

P.P.S. Recumbents also are faster and more efficient than upright bikes. Recumbents are banned from bicycle races because there is simply no contest between riders of like ability. The rider on the recumbent will far out pace the rider on the upright.

P.P.P.S. And no, they are not hard to peddle up hills! What you do is gear down and spin faster. I have seen many recumbent riders sprint up hills quickly. (Not me. My knees are more important than my pride.)

P.P.P.P.S. Dontcha' just hate sanctimonious forum posters that do not know when to quit showing off their knowledge of a topic most cyclists don't want to hear about?

[dogman]

A recumbent could be invisible, behind or beside another car. So if you are hiding behind the car, how are you seeing what is on the other side? I wouldn't call that the bike's fault, but the bike rider. You can pop out from behind a van and get killed on a regular bike just as easy.

Riding out in the streets, being predictable to the cars is very important to saving your life. But on a regular bike, wearing yellow, I still get right crossed regularly when I want to cross a crosswalk going straight ahead with the crosswalk light saying walk. Makes you want to carry a flag on a 10 foot pole to wave under their noses. Hey, guy using the crosswalk with the signal saying walk here! They still don't see you even when you have been parked side by side for about 3 minuites.

[Russell]

36V revisited

Ever since I purchased a 48V/10Ah LiFePO4 battery I’ve turned into something of a power hog using as much as 66% more energy per mile as I once did when I rode my first E-bike early this year. Back then I could stretch a 36V/9Ah SLA pack (5.4Ah usable) to 32 miles. When I switched to using 3 Bosch Fatpacks (~6.4Ah max) I got a little faster and used slightly more energy but I was still able to stretch the little pack out to 32 miles and once even 37 miles, admittedly with a conservative throttle but still using the motor to assist at least 80% of the time. Back then it was pretty easy to run in the 6-7 Wh/mile range since the Bafang on 36V wasn’t capable of high speeds. Still even when I added a 12V SLA in series with the Fatpacks I was able to keep energy use in the 7-8 Wh/mile range while boosting average speed by at least 1 mph. Again since the SLA would die at just over 4.7Ah I needed to conserve most of the time. Much of that restraint flew out the window when I got the 48V/10Ah battery and ever since I’ve been using power in the 10-11 Wh/mile range with that dipping to 9 Wh/mile only on longer than normal rides. The 10-11 Wh/mile range isn’t bad but that’s because there is still one tiny thing holding me back…the Bafang motor. If I were to use full power all of the time I’d not only probably consume double the power, I’d send the poor little Bafang to a premature grave from over-heating.

This brings me to the purpose of today’s ride at 36V, to answer the question “could I ride with greater efficiency at 36V…or at all for that matter or had I just gotten lazy”. Anyway the other reasons for the ride at 36V were to discharge the Fatpacks since I don’t know when I’ll use it again this late in the season and because it’s chilly out (47F, 8C) and a slower ride with less wind-chill seemed like a good idea.

The power drop at 36V compared to 48V was instantly noticeable as was the need to use far more throttle. On the plus side, the motor operated more quietly. It didn’t take too long for my internal speed-O-meter to adjust and on the bike path portion of the trip I settled into spinning one gear lower and perhaps 1.5 mph slower than at 48V. With virtually no one else on the path today there were no ‘rabbits’ to pursue or riders approaching from the rear to egg me on either so it was a nice serene ride. Once off the path the wind and grades were more noticeable than at 48V but it wasn’t until I hit the wide open road that the lower speeds felt, well…pokey. The last 4.5 miles of this route is mostly a lightly traveled frontage road with for the most part a 50 mph limit. With the 3 Fatpacks half-empty and an unfavorable wind full throttle and pedaling yielded speeds of 18-20 mph. Generally at 48V I’m flying along this stretch at easily 5 mph faster. I ended the ride at the slowest average speed I’ve done in a long time, 16.4 mph. I have noticed with the advent of colder temps my speed has dropped on the past few rides so it’s partly that. Aside from the lower speed I didn’t make any effort to conserve power using the throttle most of the time to provide some assist and I ran full or near full throttle the last 4.5 miles of the 18.2 mile trip. The end result was 7.96 Wh/mi, not stellar but I have no other rides at 36V on this bike to compare it to at this locale.

After a brief rest and a little snack I loaded up the 48V battery for another trip. I wanted to see what the power consumption would be if I rode the exact same speed over the same route as I had just done at 36V. It took a light touch on the throttle to do it but It seems I had quickly adjusted to the lower speed, in fact due in part to being less fresh than the first ride I found at the half-way point I was running at about a 0.4 mph deficit. No matter once out on the country roads I spun up the legs and the motor to quickly make that up. The challenge was keeping the speed to 18 mph on that last 4.5 miles of open road which took only about half throttle at 48V. A half-mile from home I hit the same average speed as before then just held it there. The result was perhaps not surprising; to cover the same distance at the same speed I used an almost identical amount of power, in this instance 7.78 Wh/mile for 48V compared to 7.96 Wh/mile for 36V. The difference was it was easier to ride slower at 36V, which also should come as no surprise.

Before I purchased the 48V/10Ah battery I went back and forth between it and a 36V/15Ah version. I would likely get better range with the latter but the former is definitely more fun and with a lot of self control it can be ridden at the same speed resulting in lower power consumption per mile.

Oh yeah and the answer to “have I gotten lazier?” is; well perhaps a little but I still come home from each ride sweaty and heck I rode 36.4 miles today and 3,700 miles this year, that’s gotta be worth something.

-R

[sparky]

Hey Russell,

Really interesting test. Thanks!... I, like you, crave the speed of 48V LiFe, so there's no going back. In fact, I'm thinking about adding a booster "turbo button" to mine for a boost for speed on long, flat sections...I'm running a 48V 16Ah Ping v2 and a 72v C'lyte controller. Seems like I should be able to add at least 12V more and still have some overhead for the controller.

For your booster pack, did you use any diodes or anthing like that? Was yours "always on" or did you switch it in (aka turbo button)? Any recommendation for this application? I'd like to use something light, something other than SLAs... thanks!

Scotty
(PS I'm in the Twin Cities...what part of WI are you?)

[kevo]

Russell.

While generally a lurker on endless-sphere, I must say your posts have inspired my ebike ambitions with Bosch 36V packs.
Thank you so much for all your posts and feedback on incredible ebike progress.
-K

[Russell]

Hey Russell,

Really interesting test. Thanks!... I, like you, crave the speed of 48V LiFe, so there's no going back. In fact, I'm thinking about adding a booster "turbo button" to mine for a boost for speed on long, flat sections...I'm running a 48V 16Ah Ping v2 and a 72v C'lyte controller. Seems like I should be able to add at least 12V more and still have some overhead for the controller.

For your booster pack, did you use any diodes or anthing like that? Was yours "always on" or did you switch it in (aka turbo button)? Any recommendation for this application? I'd like to use something light, something other than SLAs... thanks!

Scotty
(PS I'm in the Twin Cities...what part of WI are you?)

I don't so much crave the speed of 48V as I get used to it and anything less feels slow. My 36V Bafang is no speedster at 48V with a top speed of 23.5 mph but it still provides some good assist at 25-26 mph allowing me to ride faster than all but the swiftest of Roadies. On average I don't ride all that much faster on 48V than on 36V but of course any extra speed is all from the motor meaning power consumption rapidly rises with small incremental increases in average trip speed.

My 12V9Ah SLA booster was used in series with a pack made up of 3-36V 2.2Ah Bosch Fatpacks. The Fatpacks do not have a BMS to worry about and of course neither did the SLA so I did not need any protection diodes. Because the capacities were close I simply put them in series. In practice the SLA would die at about 4.7-4.8Ah, well before the LiMn Fatpacks, so while I tried to limit my use to that level I didn't care about getting long life from the SLA's. I got 3 of the SLA's with my first kit and quickly ditched them in favor of the Bosch Pack however using them as a booster was a way to put them to some use.

Today the temps here in Southeastern Wisconsin reached the low 60's and since that's a rarity now I had to get out and ride. I once again chose to ride on the little 36V/6Ah pack all by itself. All it really took was a change in mindset to ride more slowly and for much of the ride I didn't miss the extra voltage, in fact the less hurried pace is more serene especially on the narrow and wooded bike path portion. After a while I found I wasn't using much power so instead of turning for home early as I had planned I continued around my full 31 mile course. In the end I used less power than I have in quite some time, just 6.2 Wh/mile, and still had a thoroughly enjoyable ride, the only difference was the lower average speed of 16.4 mph. I'm wondering now if I should not have gone for the 36V/15Ah pack instead of the 48V/10Ah


-R

[sparky]

... I'm wondering now if I should not have gone for the 36V/15Ah pack instead of the 48V/10Ah


-R

Thanks for the help on the booster!

Let me know if you want to unload your 48V/10 to help you finance a 36V/15....would like to build a bike for my speed freak wife!

[Russell]

I'm wondering now if I should not have gone for the 36V/15Ah pack instead of the 48V/10Ah

-R

Within an hour after writing that line I had purchased a 36V/20Ah battery through eBay. Comprised of 100 small cells and boasting unimpressive specs it would never be my first choice especially at the retail price. My 36V/6Ah Bosch pack however has 60 cells and that works well and besides for $220 delivered it was a pretty good bargain…if it works. Well today the postman delivered it so of course I had to try it out right away. It came with a compact little 2A charger which is woefully underpowered for such a large pack. The pack was already mostly full, I forget the voltage I read, but I put it on the charger for a short time just the same. The charge voltage got up to a wee bit over 42.0V and it wasn’t done yet but I was impatient to ride so I disconnected it. I also opened the charger and dropped the open circuit voltage to 42.0V from 42.4V to go easier on the cells and hopefully extend the life of the pack which the previous owner said had 20-25 cycles on it.

The battery was purchased here by the original owner;

http://www.campsolution.com/li-ionbatterymodule36v88ah288whwithpcbready40x1865010s4p-3.aspx


Here it is packed in my rear Topeak bag;

snug as a bug in a rug

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I hit the road at 11:30 local time on a gray overcast 55 degree day with a brisk wind. The pack voltage started out at 41.9V so while the Bafang was not as fast as with the 48V pack it was still fairly strong. I wanted to test the capacity of the pack but didn’t want to ride forever to do it so for the first 20 miles I used close to full throttle much of the time easily pedaling at 19-20mph. At 25 miles out with 7Ah used already the motor felt noticeably weaker and I started to fret over if I’d even be able to squeeze 15Ah out of the battery. It wasn’t any help that as I turned back I was headed into the wind, it also feels slower on open roads than on trails or suburban streets. At 10Ah used I had traveled 35 miles, definitely not an economy run as I have done over 30 miles on 6Ah(36V). At 38 miles I stopped briefly to scarf down three fun-sized snickers bars (mental note: pick up more candy for trick or treat ). From this point on it was full-throttle at all times. I noted at 13Ah used I was still getting 3 amps of assist at 19 mph, which is meaningless to the reader but told me the battery was actually delivering pretty much what it should at this point. Just before 14Ah used I climbed a short 12% hill and at the top the speed fell to 8 mph with pedaling vs. 11 mph, also with pedaling, with the 48V LiFePO4 pack. I tried shifting to my small chainring but the steel cable had rusted in position from never being used. Two miles from home and I got rained on, not much mind you but it hadn’t warmed up a bit and I was getting a little chilly. When I arrived home I had completed my longest e-bike ride yet at 49.8 miles at an average speed of 17.3 mph and consumed 15.170Ah/570.1Wh. That’s a high 11.45Wh/mile but not unexpected given my limited input, especially on the first half of the trip. The battery resting voltage at the end was 37.22V and that along with the Vmin of 34.66V told me I plenty of juice to spare…maybe even 5Ah????

Come spring I’d like to use this battery for some much longer rides and if I pick a nice day when I’m feeling especially energetic who knows I may even try for a century which should be possible if I would limit power consumption to the low 6 Wh/mi range. For every day use though I think I’ll stick with the 48V/10Ah LiFe battery. While I don’t ride all that much faster with the 48V pack I do like having the reserve to be able to easily spin up to higher speeds. If the weather holds I think I’ll load the 36V/20Ah pack on my Raleigh ebike presently running a 24V GM Mini Motor and heat that puppy up a bit .



-R

[Russell]

The little motor that has never let me down in 3,000 miles up and quit on me today. The only good thing was that it died 4 miles from home instead of 15 or worse during the two proceeding rides which took me as far as 25 miles from home. I have been pushing the motor hard lately and today back on the 48V battery was no exception however the failure itself came swiftly, as I reached the top of a hill the motor simply quit. Applying the throttle resulted the motor making a hammering sound indicative of a hall sensor failure. I was hoping it was a connection or controller problem but alas no the connections were all fine and the motor has the same problem on an identical spare controller but runs on my sensorless unit. Oh well I was planning on taking the Bafang apart for a full inspection sometime during the winter this failure simply moved up that timetable.

-R

[docnjoj]

[quote="Russell"]The little motor that has never let me down in 3,000 miles up and quit on me today."

I am sorry to hear of the motors demise on 48 volts. I really miss the "punch" since I have been on 36 volts, Soon since I have the gears if they get mashed, to repair with 1 steel. I haven't fried a Bafang yet (just the gears) and I ride pretty conservatively for a big guy on a big trike but I was using 20 Ah/mile or more with the 48 volt Ping. Good luck with repairs, Russell!
otherDoc

[Russell]

I hooked up 5V between the red and black hall power wires and checked the yellow, blue and green wires. The Yellow wire did not change states as I rotated the wheel backwards.

started the autopsy.

After 3,000 miles and two-thirds of that on 48V I expected some wear on the gears but they look great.

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-R

[marshy]

The little motor that has never let me down in 3,000 miles up and quit on me today."

It's a sign Russell, a sign. Go the ecitypower cutesy motor!!

[dogman]

It would be cheap and easy to get an identical bafang, and just pop the motor and gears into the laced wheel.

Over on the Aotema controller thread, Docnjoj reports that the sensorless controller runs his bafang fine. Perfect for motors with blown halls.

[Russell]

I found a frayed red wire which supplies 5V to the hall sensors.

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I spliced in a new wire however it did not help, the "Yellow" hall sensor was still dead. I didn't see anyway I was going to be able to replace the sensor but then I thought of something else...

Behold the first 24V 250W GoldenMotor Mini Motor which was delivered to me with a cracked flange.

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The case for the Mini is different than my polished QSWXB however I always figured the GM Mini to be a Bafang QSWXH. A quick check with the calipers confirmed the motor cores were the identical diameter therefore I swapped the covers and slid the Mini motor core and gears right in the old Bafang case. Reterminated the motor phase leads with Andersons, reinstalled the wheel and spun 'er up...and it looks like it is golden

-R

[Russell]

I'm feeling under the weather, the two recent 50 mile rides in the cold chilled me to the bone and softened me up where I felt pretty lousy during yesterday's 31 mile ride especially when dragging my butt up a 8% hill with no motor assist. Still I wanted to see how the "repair" would work out on the road and took the bike out for a quick 2 mile test ride. I was sent a replacement 24V 250W Mini from GM which I installed on my Raleigh E-bike a while back so I knew what to expect however the low-end torque of the 24V Mini really does pale in comparison to the 36V Bafang. The 36V Bafang even at 36V could spin the front tire from a stop but the 24V Mini at 36V generates very little thrust. The 24V Mini does have speed, about 23 mph on a 36V pack compared to about 18 mph for the 36V Bafang on the same battery, however where I don't mind the lower torque on the Raleigh I would prefer a stronger motor on the every day Kona so I will likely replace the Mini on this bike.

-R

[docnjoj]

That is really interesting, Russell! So the geared GM and Bafang are essentially identical! Good info for us Bafang lovers. Did you have any difficulty opening the cases for either motor? Oops, I just looked at the photos and both seem to have the old screws, which were easy to open. The new one, well, we will see when the time comes!
otherDoc

[Russell]

The newer GM Mini is quite easy to open. The older Bafang on the other hand has an almost invisible seam between the cover and the case which I thought might be a bear but all it took was a sharp utility knife to crack it open. The case diameter of the older Bafang is about 9mm larger than the Mini so I was pleasantly surprised to find the cores were the same size

Mini (top) Bafang (bottom)

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Still buying the 24V GM Mini was an experiment for my other bike as a way to use the 36V controller and battery I had and still get some decent speed. It works in that way however 700C wheels are a bit too big for the 24V Mini to produce good thrust. The motor can essentially be thought of as a "36V 20 inch" model with its 9.1 Revs/V compared to the 36V Bafang's 6.4 Rev's/V so it would perform better in a smaller wheel. I'll be replacing the Mini on this bike and while I'm at it I'd like to get an eZee or Puma but I suspect due to price I'll end up going with one of the new Cute motors, another 36V Bafang or 36V GM Mini.

-R

[Russell]

Oops I broke it again

In search of more low-end grunt from the 24V Mini I soldered up the shunt to restore the controller to around 22A max. The extra amps could be felt but it didn't provide all that much more thrust and it still didn't spin the front tire the way the 36V Bafang would even at 15A. The next step was to use the 48V pack on the 24V Mini, something I had already done on my other bike which received a 24V Mini a while back, that motor survived and I'm figuring on replacing this motor anyway so what the heck.

The weather today with temps in the low 70's, in WISCONSIN, was a real gift so I headed out for my usual 31 mile route. The thrust was still fairly low and acceleration into the wind is slow but give it some pedal power and 30 mph can be hit quite easily. On the flats the top speed of the motor alone was about 29 mph. A few high speed runs had used considerable power so I backed off and settled down to a a high-normal pace. Aside from right off the line however I was generally pleased with the motor on 48V though it did take a light touch on the throttle to ride under 20 mph.

Near the end of the route are a few good hills to check the climbing performance and while the low end is lacking if I kept spinning to keep the speed up it climbed quite well, almost 3 mph faster than the 36V Bafang at 48V/15A actually. Peak amps/power was 21.59A and 1,086W, respectively though on the hills the controller held just under 20A. That's a whole lot of power to pump into a 250W Mini and as I've said on other occasions and threads if you pump 1000W into a 250W motor continuously something is gonna break...and it did

After climbing two 7-8% hills at full power followed by a longer full throttle 3% climb and then holding top speed for another mile the motor completely quit. There was no response at all this time around from squeezing the throttle. I did notice the WU meter was reading higher than normal with a standby current of 0.15A compared to 0.03-0.04A. The meter read normally when I disconnected the hall sensor cable so it looked like another dead sensor. I was beginning to wish I would merely turn my gears into peanut butter as that's a pretty simple fix. I pedaled the last 3.5 miles wishing I had my ecitypower controller on this bike since that one would get me home without halls.

When I got home I checked the hall cable and found the red and black wires were shorted; wonderful I thought another useless motor. After opening the motor I found something that gave me some hope. I poked around the motor with the ohmmeter connected between the red and black leads and found the short opened up when I pried up a couple of wires. It turns out the wiring they use for the hall sensors does not have a high-temperature insulation and in the heat a looped red and black wire melted together! I repaired the wires and applied some shrink tubing and that seemed to have done it...hallelujah.

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The last thing I did was open the controller and undo the shunt mod to restore it to around 15A peak. If the good weather sticks around I may even get a chance to try out the repair.

-R

[docnjoj]

"Houston, we have a problem"! I have put 1500 peak watts through my Bafang and so far no destruction. I guess it is a matter of time! Thanks for the update, Russell!
otherDoc

[Russell]

Temps here in Wisconsin are still quite mild (mid 50’s) so I got out to test the repaired GM Mini Motor core in my Bafang case. With the controller shunt unsoldered the current now peaked at 16.11A and peak power was down to 813W. Due to that lower current level, which at full throttle was limited to about 14.4A, the top speed was down significantly to perhaps 24 mph. The motor alone doesn’t accelerate quickly so to check top speed in a limited distance I needed to help spin ‘er up to around 26 mph then run on the motor alone until it appeared to reach equilibrium. While the no-pedaling top speed is artificially limited now that 14 amps remained available all the way up to 31 mph and the current was still 10A at 33.5 mph or about the fastest I could spin my legs with my top 39/12 chainring/cog combo. In fact the 24V motor is wound so high that on 48V there is no speed I can go where I don’t have some boost available. On one hill I generally coast down and hit 36 mph tops the motor took me to 37.4 mph!

I was cruising at a higher than normal speed with a good number of high speed runs pushing both the motor and battery hard. It was then with some trepidation I reached the twin peaks of death as I call them (Nah I really don’t) where the Bafang met its doom and shortly thereafter where this Mini motor core hall sensor wires melted . Up the hills on part throttle the controller allowed a bit more current (~15.5A) and with power at about 730W the 7-8% hills were easy to climb at 12+ mph. I flogged the motor the remainder of the way home using more power from the battery than I ever have over this 31 mile route (9.3Ah/455Wh). The motor covers were only warm but when I did what Dogman sez and checked the axle I found it to be HOT (hot so it was uncomfortable to hold on hot).

I definitely pushed the motor hard today but I wanted to regain some confidence in it. I don’t want to go out on each ride wondering if the motor will last. My original Bafang lasted as long as it did (3,000 miles) because I kept power reasonable and tended to conserve the limited battery capacity I had. When I got the 48V/10Ah LiFePO4 battery I ran harder longer which likely contributed to a premature death of the Bafang and when unbridled with a 22A controller quickly overloaded the replacement Mini core wiring. Still to their credit neither motor twisted their gears in a knot or burned windings and who knows how much they would take with high temperature insulation on the hall wiring or no halls at all. This 24V core is however out of place on this bike which I prefer to ride closer to normal cycling speeds so while it works fine it will be replaced come springtime. In the meantime I think I’ll revert once again to 36V for the next ride, weather permitting (always gotta say that in November).

-R