Warren's 350 MAC mid-drive (finally) recumbent

Time for an update.

After another 800 miles, it finally got to where the motor would cut out in less than a mile, and it would take 15-20 minutes before it would work again. At this point I could get it to fail with the bike mounted on a stationary trainer. Turns out one of the motor hall sensors was shorting out. I ordered a new motor hall PC board, with leads and halls installed. I was off the bike for 25 days, waiting for parts. At that point I figured I would verify the problem once more, before tearing the motor apart. You guessed it. Everything worked perfectly for the next 170 miles. And now the problem is gradually coming back.

The puzzle is solved...condensation. Nothing else makes sense. When it gets to be a nuisance again, I will pull the side cover off, and go from there. I could drill a small hole in it to spray some sort of circuit board cleaner in, as some others have done. But, more likely, I will drill three, one inch holes, in the cover, and install mini-louvered panel vent plugs, from McMaster-Carr.

I am much relieved that the electronics are still good after 10,144 miles. I just installed my fourth set of tires, and chain. Without water in the works, I expect this setup to go at least 20K miles without trouble.
 
Nice bike!
Have you thought of using sensorless controller? The come for 25$ its always nice to have one in spare :)

If you run only 350w the a converted bafang swxb would also be an option. it might be slightly more effcient and the chain will last longer with the CB style drivetrain.
 
crossbreak,

Thanks.

I don't think I could run sensorless, with a geared hub motor. With the built in freewheel, wouldn't the motor have a 50-50 chance of starting backwards?

To clarify the chain situation...the chains are in practically new condition after 3,333 miles. I replace them, because they are inexpensive 8 speed chains, and I am hoping to never have to replace the cassette, motor sprockets, or chainring. It is an interesting experiment.
 
No. The turnig direction is defined. In middrives sendorless mode works even better since the chain has to be tightened :) it is also slghtly more efficient since the Controller always uses the perfect Timing. Sensorless is also more reliable.
 
Check your throttle and hall connectors. If they get dust inside, it makes the motor cut out. It could be nothing to do with the motor.
 
Veloman,

I have already caught it failing on a stationary trainer. Rotating the motor backwards, one of the halls would stay at 4+ volts. The other two would cycle between zero and 4+ volts. Everything looks clean and the halls and PCB are still glued solid. No apparent wire abrasion.
 
Since typically the hall lines are pulled up internally to the controller, it's possible there is a poor or broken connection between the hall inside the motor and the outside connection being measured at.
 
ammberwolf,

I am seeing 4+ volts continuously, when the hall is not working. That would mean a short, not an open. Am I correct?

If it is not a short, then the hall must be failed in the on condition. Is that the normal failure mode for halls, or do they tend to fail open?
 
Normally, a hall sensor *grounds* the connection when active, and otherwise the output is pulled up to "5V" (usually a little less than that) by internal resistors in your controller. Sometimes the resistors are on the hall board in the motor.

So seeing a continuous "high" on the hall line indicates the hall connection is open somewhere between your measuring point and the hall output, or the hall is defective in some way.



(If there is no pullup, like if your sense wires to the controller are not connected when measuring, usually you'll see what looks like no output from the halls, as they will be floating in voltage unless active, pulled down to ground for sure only whne actually "on").
 
If the wire is actually broken somewhere inside, then it could heal by being bent back to where it touches again. Or if it's got a hall lead broken off at the hall casing, it might also someitmes touch and sometimes not, kinda depends on vibration mostly. I've seen a lot of that type of problem in electrical stuff over the years, especially low-voltage low-current applications.
 
Yeah. It is maddening. Which is why I think I will switch to a sensorless controller.

I just got back from a 58 mile ride. It worked perfectly for the first 25 miles, then it cut out once. Rolling off the throttle, and back on fixed it. I could live with this forever. But at about 30 miles it cut out going up a steep hill, so I was cranking along in low for about 30 seconds, wondering if it would ever start. It took 2-3 tries before it worked. At this point it was 93 degrees, 59% humidity, 107 heat index, and a huge black storm cell was cracking lightning over my right shoulder! I don't need an electrical problem at times like that. :-(
 
Update:

I agonized about whether to try a sensorless controller all spring. I lost about 7 weeks of riding all told. Opinions were all over the map. So today I installed one of cell_man's sensorless Infineons.

http://em3ev.com/store/index.php?route=product/product&path=38&product_id=136

I can see why scooter guys wouldn't want one. It chatters about half the time, from a dead stop, with my feet dangling. But I never ride that way. I have no freewheel between my cranks and motor, so any time the motor is on, I am pedaling. I rode 40 miles, 20.2 mph average, 10.5 Wh/mile. It works exactly like it did with the sensored controller...before the hall failed! No more f__king halls. :)

10,426 miles, so far
 
Yesterday's ride was one of the nicest, so far, this summer. Low wind, low humidity, lots of high clouds covering the sun, but still bright, if you know what I mean. Never got out of the 70's.

107.6 miles, 5:25.40, 19.8 ave, 40.4 max, 9.0 Wh/mi, 11,000 miles total!!!

http://www.evalbum.com/4525
 
Warren said:
crossbreak,

If that is the case, why on earth would anyone bother with hall sensors? The additional parts, and potential for failure is huge.

Historically, a sensorless controller required the cyclist to pedal upto 3-5 mph and so the lazy saps who wanted to ride their bike like a moped helped create the "sensored standard". However, for those of us who are perfectly okay with pedaling, sensorless works perfectly and I personally prefer it. I'm running a 5-year old sensorless controller and it's still running strong.

Also, it appears you need sensored if you want to run at 2+ kw with currently available products. (Well, actually, I think it's 2.8+kw, with Lyen's 72v 40A sensorless controller)
 
I lost seven weeks riding this fall, waiting patiently for my local sheet metal shop to shear and bend up my new battery box. The old one developed a crack about six months earlier, and I waited until it actually failed before I made another. Then the crappiest weather in years set in...but enough excuses. I did manage to roll over 12,001 miles before New Years. Looking back at my logbook, I only jogged 186 miles, rode 1,534 miles on my pedal bikes, and did 4,391 miles on the e-assist. Not that good, considering this was my first full year of retirement. :-(

Hoping 2014 will be better, Happy New Year!

http://www.evalbum.com/4525
 
Coldest winter in decades. No more than a few dustings of snow, but bitter cold. Only got 408 miles on the e-assist, so far, for 2014.

I replaced my last shift cable after 4777 miles as preventative maintenance, when I replaced chains and tires. This time I figured I would see how long it would last. It broke at the clamp bolt, on my latest ride, nine miles from home. Installing the spare I carry took two minutes. I got 5734 miles on this one. It will be time for routine replacement of tires and chains again in 600 miles. By then we should be into decent riding weather. :)
 
I have had this bike for three winters, so far. The winters are getting worse.

winter 2011-12 was 1573 miles, and I was still working full time!

winter 2012-13 was 1171 miles

winter 2013-14 was 1047 miles

But winter's grip has finally broken, two weeks into spring. :)

http://www.evalbum.com/4525
 
Today was perfect. Started at 11:20 am, 65F, almost calm, clear. The same, but up to 77F when I got home at 3:50 pm. I rode to a diner for lunch.

73.49 mi, 3:49.19, 19.2 av, 44.4 max (than you for the draft Cadillac), 10.4 Wh/mi. Used 9 cents worth of electricity. Saw 6 roadbikes...I think that may be a record.

Now at 13,334 miles. Time to replace chains and tires for the fifth time. I have been replacing them every 3,333 miles. This last time I didn't even oil the chains once. Pulled out of the package, and installed with the factory lube on them. Only wiped them off with a rag a few times after riding on wet gravel for miles. As always, I see virtually no chain wear. Measuring with a steel machinist scale, the distance from pin center to pin center is still 12". My chain checker shows almost no wear. You can see about 1/64" lengthening over the whole length of the chain. My goal is to see how long I can run the same cassette, and chainring.

I retensioned the spokes on the rear wheel back at 11,888 miles when I noticed a ticking sound, and found a loose spoke on the drive side. Other than the hall sensor problem, and a cracked battery box, this bike has been so reliable I can't believe it. Have not needed to repack wheel bears or headset yet. As play-free and smooth as new. Brake blocks look like new. Every couple thousand miles I hit the rims with emery cloth when they get grabby.
 
I spoke too soon. The other day I gave my front wheel a turn and it felt a bit rough, so I pulled the hub down. Not much grease left in there. More like black gunk. I wiped down the cones and cups, and looked at them with a loupe. One cone had pitted. The 3/16" balls also mic'ed a thousandth smaller than new ones. So I replaced the cone, and all 20 balls. New grease and all feels good after another 95 miles. I will add repack wheel bears every third tire change to my maintenance list.

Yesterday was beautiful, upper 70s, dry, but very windy. 18.1 average going out into the wind, 22.1 coming back.

63.60 mi, 3:09.50, 20.1 ave, 39.3 max, 10.7 Wh/mi. 13,432 total so far.
 
Finally took shots of the new battery rack from December. Also of my new right side mount and pannier for overnight rides. With the amazing Satiator charger from GrinTech, clothes, toiletries, food, etc. came to 12 pounds.

I got back yesterday from a credit card tour up to the Blue Ridge Mountains. The three nicest weather days, so far, this summer. In three days I saw maybe twenty bicycles. The only other electric vehicle was a Tesla on the Parkway!

Wednesday, home to motel. Missed turn added a few miles:
67.12 mi, 4:11, 16.0 av, 41.4 max, 9.6 Wh/mi, 3799' climbing

After shower and nap, motel to Ravens Roost to Tastee Freez and back to motel:
29.05 mi, 1:39, 17.5 av, 42.3 max, 10.5 Wh/mi, 3011' climbing

Thursday, motel to Vesuvius to motel:
63.21, 3:57, 15.9 av, 41.9 max, 11.5 Wh/mi, 6873' climbing

Motel to Waynesboro, riding around town, and lunch at Stone Soup, back to motel:
22.26 mi, 1:58, 11.2 av, 38.5 max, 6.4 Wh/mi, ~600' climbing

Friday, ride home:
64.67 mi, 3:44, 17.2 av, 37.4 max, 8.8 Wh/mi, 2507' climbing
 

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Three years on the road today, over 5000 miles a year. Rode to Gordonsville for a snack. Pushed a bit. Turned in my best average speed in two years.

48.46 miles, 2:13.19, 21.8 av, 38.0 max, 541.74 Wh, 13.83 Ah, 11.2 Wh/mi, 15948 miles total.

Still have my EV grin.
 
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