E-bikes (page 2) - CycleBlaze

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E-bikes (page 2)

Gregory GarceauTo Scott Anderson

I'm weakening, Scott.  I don't wear that jersey all that often any more.  It's a little too tight these days.  Either my pectoral and abdominal muscles have bulged out from so much cycling, or the jersey has shrunk.  So I've decided to give it to you.  Send me a forwarding address and your credit card number and expiration date.  I'll take it from there.

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1 month ago
Mark BoydTo Gregory Garceau

I have the original LHT, upgraded a bit,  and it has been my upright touring bike in Europe since I flew to Budapest with it in May of 2008. I didn't have to fly with a bike again, despite touring in Europe, most of the  years between 2008 and 2015 when I flew with my Giro to Hamburg. The last time I toured in Europe was 2018. In 2019 I decided to stay in the US and 'collect  - ride through' the last three of the lower 48  states. That tour ended in Canada because of my back troubles and then COVID hit. I don't know when I'll get back on my LHT.

It would be easy to convert my LHT to an e-bike, but more expensive in Germany and here and I'd have to deal with lots of regulations about e-bikes. 

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1 month ago
Steve Miller/GrampiesTo Mark Boyd

My image of ebike stems from the Mosel bike route in Germany, where it seemed the vast majority were e assisted riders, who were older, staying in guest houses, and pottering along at far lower speeds than the usual younger riders of much lighter unloaded regular  bikes. The  admittedly annoying phenomenon of riders with throttle bikes and fat tires bombing along past everyone is something I have not seen much. But even more annoying (and dangerous) are the gas scooter people permitted on cycle trails in Netherlands.

I am not at all concerned about how people choose to travel, from roller blades to jet planes. In terms of blogging, it's self regulating because we only have to read blogs that we find interesting. In terms of safety, I think 25 kph is plenty fast on a bike trail, and I am more crabby with the 50 kph lycra warrior peleton than with the 25 kph e biker.

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1 month ago
Mark BoydTo Steve Miller/Grampies

One of the issues of converting a bike to an e-bike in Germany is that e-bikes that can be legally ridden on German bike trails must be limited to 250 watts of power from the motor and 25 kph speed. These are legal limits and they are enforced. Similar regulations exist for other EU states and the UK.

One of the bikes I have e-biked has firmware that can be used to set and enable/disable those limits so that it can be legally used in Germany and some other EU countries. I discovered that that setting was on by default when I was running out of energy on the steepest climb I regularly ride. I had no problems on that climb on using the older, less sophisticated firmware, on the same TSDZ2 motor/controller with the same battery. On the system with the newer firmware  I had to find out how to turn that setting off.

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1 month ago
Steve Miller/GrampiesTo Mark Boyd

I am glad this is a forum and not our blog, because we are delving into a pretty abstract and geeky area. I think there are questions of the true wattage - power output of a motor, how long it could keep that up without overheating, its "official" rating, and any software controlled power output limit. In the U.S. where power is revered, probably the wattage of motors, like up to 900 or more, is exaggerated by manufacturers. But in Europe where the legal limit may be 250, then motors may routinely just be labelled 250. Maybe, as in your case, motors may be capable of more than 250 but for legal purposes are limited to 250.

One clue is this compliance label from Reise Mueller:

That "EN 15194" could be a testing standard that the bike conforms to, unless Reise Mueller takes any pages from VW!

Anyway, the smallest rated motor I seem to be able to get here for our Bike Friday conversion is nominally quoted in the advertising as 350W. I'll check to see if that can be limited in the controller, but honestly I can not see any gendarmes flagging down us aged Bike Friday riders to put their steeds on a dynamometer, or something!

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1 month ago
Steve Miller/GrampiesTo Steve Miller/Grampies

The plot thickens a little bit. The motor I bought (Bafang 310) maybe is rated at 250. But the seller (Grin Technologies) says:

"The nominal power rating of 250W from Bafang doesn't mean a whole lot. These motors can put out 20 Nm of torque continuously and upwards of 40 Nm for short times without overheating. At higher speeds (like 40 kph) this translates into a solid 600-700 watt continuous power levels, while the corresponding power at lower speeds is more like 200-300 watts. Usage beyond 50 Nm is not recommended as there is high risk of stripping the gears."

They follow this with graphs that show the power output varying with RPM, and indeed going as high as 600 watts at some medium rpm and totally tanking at higher RPM. Too hard for me!

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1 month ago
Mark BoydTo Steve Miller/Grampies

Yes, it is complicated. The motor used, the battery used, and the firmware used by the controller that is the interface between them, are all involved. In my case, the TSDZ2 kit with the open source software installed on the controller  can have a power output limit between 250 watts, using a 36 V battery and 750 watts, using a 52 volt battery. As you mentioned, using the higher power output limit can destroy the actual motor by heating the permanent magnets up to the temp that causes them to permanently loose their magnetism if run at too high a power output for too long. 

The software I use actually can monitor magnet temperature and shut down the system before the magnet temperature gets too high. However, that requires connecting a temperature sensor to to controller and mounting it on the actual motor. This is non trivial and not necessary in my installation which currently uses a 36 volt battery. My experience is that, when the 250 watt limit is on, my system shows a power output max of 220 W, and when it is off, a power output max of over 300 watts. For comparison, I can still produce about 300 watts for a short period of time on a very steep climb and sustain about half of that when climbing a long hill. 

With the motor adding about 300 watts, I regularly climb, unloaded, short 20% grades. On my only e-biked tour, using an assist setting that asked the motor to roughly match the power I generated, I was able to climb two 4 mile long, hills with 8-9% sustained grades - I coasted down them at over 40 mph-  at 4 to 5 mph on my loaded bike without being totally wiped out or overheating the motor. The effective temperature - in north eastern TN last July - was over  100F so there was more problem with me overheating than the motor overheating. 

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1 month ago
Jacquie GaudetTo Steve Miller/Grampies

I live with a "lycra warrior" and know many others.  They aren't young guys, though, and I don't think they can go quite that fast unless gravity-assisted on a descent, though I can't be sure since I can't keep up.  Plus, they generally avoid bike paths as being too crowded with slow riders.

The scary ones, to me, are the middle-aged people who got an ebike as their first bike after having not ridden a bike since they got their drivers' license.  Some of them are downright dangerous, both to themselves and to others.

Here in Victoria for the past 3 weeks, though, I've twice seen groups of adults taking a bike skills course, something I never saw in Vancouver.

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1 month ago