Switched from SWXB to Q100H

eHomer

Esteemed Pedelecer
Aug 20, 2012
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I fitted an Ebay kit 3 years ago to my German Alubike, a full suspension step through hybrid with 700c wheels.

With help from the forum I've gradually upgraded the parts, now keeping just the original lithium iron 36v 10ah battery.

I first changed the KU65 controller for a BMSbattery S06S sine wave controller and lcd display. That was a big improvement, more flexible PAS levels, and a bit quieter.

I've now just changed the front wheel motor from the original Bafang SWXB 250w 36v to a Q100H 350w.

I'd posted a thread about trying to buy one from a UK supplier to save the shipping cost from China, but Dave talked me into just buying the motor and building the wheel myself. Great advice, as always.

I finally followed his recommendations fully and used 14g spokes, and it turned out really well, a very satisfying build with a very true and nicely tensioned rim.

I've just returned from my regular 22 mile run and the difference between the two motors is quite surprising. even though the Q100H is physically so much smaller, it's much quieter and more torquey than the SWXB. It's the 260rpm version running at 36 volts, in a 700c wheel.

I found that PAS level 2 was ample assistance, giving me an average of about 16-18 mph with moderate pedalling. PAS level 5 went up to 20mph plus easily, even on the 36 volts.

The Garmin graphs show the run, and the photo of the lcd panel shows only a quarter of the 10ah used up after 22 miles.

I had also fitted a 328rpm Q100 to my recumbent trike, in a 20" wheel, and was impressed with that too.

They're both small enough to almost be taken as dynohubs, yet more powerful and quieter than the old SWXB.
alubike with q100h.jpg q100h in alubike 700c rim.jpg gps data.jpg
 
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awol

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Sep 4, 2013
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Nice. It does look a tiny motor, any idea of it's weight before assembly?
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
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I've made a couple of mods to my conversion upgrade.

As I'm running the 260rpm Q100H in a 700c rim, I think I'm at the top end of how high geared it can be, so I'm taking precautions against overheating.

I can't do much about the motor other than making sure it doesn't slug away at too low a speed, but I've altered where the controller is installed. The original KU65 and now the upgraded S06S where housed in the small plastic box section at the front of the battery holder in the rack. It was always fairly tight in there with the lead connections stuffed in as well. I've been thinking that it's insulated out of the airflow as well, despite the controllers being finned aluminium cases.

I therefore copied what I did on my other ebikes, and fitted the controller inside a diecast aluminium weatherproof box from Maplin. The controller is fastened tightly inside with a layer of heatsink paste, so the whole box becomes a heatsink as well. There's sufficient spare space to neatly hold the connections as well.

I then used the vacated space in the plastic nose of the rack battery holder to fit one of those cheap wattmeters. I had a duff spare one that flashes at 48v but works fine with 36v batteries. I cut a window slot in the plastic and stuck the original clear plastic window over it. It now makes a very convenient "fuel gauge" for whatever battery is in the rack.

I've just been for another 10 mile test ride. I tried various levels of assist and also a one mile run flat out with no pedalling, where the bike maintained a steady speed of 20 mph.

The countryside around here is fairly flat, but that's offset by the fact that I weigh just under 100 kg.

I felt the controller box and the hub motor after each test, and it was barely warm to the touch.

The 260rpm Q100H in the 700c rim is surprisingly torquey , as well as giving a good top speed for a 350w 36 volt motor.

It makes no bones of pulling sharply away from a standstill to 20 mph, so I don't need to change gear downwards before stopping. A quick flick of the wrist gets me quietly up to cruising speed again with no need to pedal, (then I give assist).

alubike wiring.jpg controller case.jpg wattmeter in rack box.jpg
 
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jackhandy

Esteemed Pedelecer
May 20, 2012
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the Cornish Alps
The countryside around here is fairly flat, but that's offset by the fact that I weigh just under 100 kg.

]
Just looked at your elevation chart _ Are you sure your Garmin's not broke? ;)
Makes even the Camel Trail look steep!

Like your fuel gauge _ Makes mine look a tad home-brewed: Must make a proper bracket for it.:)
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
635
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Just looked at your elevation chart _ Are you sure your Garmin's not broke? ;)
Makes even the Camel Trail look steep!

Like your fuel gauge _ Makes mine look a tad home-brewed: Must make a proper bracket for it.:)
Yup, England's little Holland.

No wonder bikes have always been so popular there. :)
 

cwah

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Jun 3, 2011
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www.whatonlondon.co.uk
Where did you buy the spokes and rim for your Q100H?
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
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164
Where did you buy the spokes and rim for your Q100H?
The rim was from the original front wheel on the Alubike that previously had a dynohub on it.

The spokes were from a UK based Ebay seller derekscyclesonline and was ebay item number 111217126025

It's still a current listing, with a wide range of lengths, in black or silver. Although it only says 36, they did actually send 39, and they came the next day, a very good service.

Dave was absolutely right, the 14g were much easier to fit than the 13g, with no forcing through the hub holes, and quicker to get tensioned up and true.
 

jonathan75

Esteemed Pedelecer
Apr 24, 2013
794
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Hertfordshire
Nice - I would love a setup like that. Everyone is selling 350w but are they legal? Can they even be made legal? I'm forking out a fortune at the moment for the privilege of buying a 350w which apparently has merely had "250w" painted on it at the factory, i.e. the Bafang CST 36v250w, double the price of the ordinary BPM 350w, and I keep wondering if there's some way of having a 350w run at 250w so that it falls within the ambit of the legislation. Does anyone have a link to the actual law in question? Can a 350w motor with 350w painted on it (and a 350w certificate) be run on the road, so as to fall within the limits of the legislation, e.g. by having the controller limit the amps or something? I'm at law school at the moment and can't risk a criminal conviction which could bar me from becoming a solicitor.
 
D

Deleted member 4366

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No, you can't run a 350w motor legally. It has to be nominally a 250w one to comply with EN15194 and 200W to comply with UK EPAC regs. You can legally over-volt (up to 48v) and over-current any motor that has those nominal ratings. You still can't go over 15 mph.
 
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jonathan75

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Apr 24, 2013
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Hertfordshire
Thanks. I would add to the distinction you drew between the UK EPAC and EN15194 requirements, that a number of EU law doctrines fundamentally prohibit the UK enforcing the 200w requirement (instead of the forthcoming 250w) - which I'll spare everyone the full detail of (unless anyone's really keen, ha).
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
635
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A while ago I naively claimed on this forum that my alubike was 100% legal with the 250 watt motor and got shot down in flames :rolleyes:, (quite rightly).

As it was already over 200 watts and didn't have the official UK approved manufacturer's plate, it was still technically illegal, even though it had a maximum speed of 15mph and had no independent throttle, only PAS.

Whilst I wouldn't flout the law outrageously with a high powered bike capable of moped speeds, my understanding from many informed posts on here is that the Police do use their discretion (and have even apparently been instructed so), because of the very backward UK laws on ebikes compared even with other EU countries.

Although the 350watt motor can reach 20mph, I ride at a maximum of 15mph anyway, since that is the point where wind resistance starts to waste battery range, and the 350w motor is much quieter than the 250w was.

I am surprised at how blatantly the law is broken with so many 30mph DIY bikes on Public roads and paths, who's owners even publish their own youtube footage for the prosecution !! :rolleyes:
 
D

Deleted member 4366

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While I think about it, If you have a Q100 that says 250w - 350w, cross out or otherwise obliterate the bit where it says 350w.
 

jonathan75

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Apr 24, 2013
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Hertfordshire
While I think about it, If you have a Q100 that says 250w - 350w, cross out or otherwise obliterate the bit where it says 350w.
Interesting. I think you'd need the exact legal instruments in front of you to decide what the wording could reasonably support. After all, if it says "250-350" what it means is not "this motor only runs between 250 and 350 watts", surely it means "this motor has a nominal maximum of 250 or 350 watts [dependent on something else e.g. a controller]"? Otherwise there wouldn't be any point in it saying 250w at all. It ought to just say 350w.

(Maybe you'd then have to show that your controller was set for the lower limit. Although there might be legislative wording about that too.)
 
D

Deleted member 4366

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The wording is clear: " nominal continuous rating". That would reasonably be interpreted as the number written on it or on its relevant spec sheet from the manufacturer. If you could provide reasonable evidence that your motor with 350w written on it has been tested and rated at 250w, you'd probably be OK, but you still have the word "nominal" to convince them about.

Strictly speaking, the Q100 has a nominal continuous rating of 350w, but if you put an X through the 350, you can tell them that there's two versions and yours is the 250w one.
 
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eHomer

Esteemed Pedelecer
Aug 20, 2012
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How about the legality of "200W - 500W" ? :rolleyes:

As illustrated by another recent thread on here about road legal scooters, I've just been looking at a listing on Ebay from a UK based business seller.

The title in itself, says:

"48V 20Ah, ELECTRIC PEDAL SCOOTER, MOPED, BIKE, SUPERB RANGE & PERFORMANCE
NO DRIVING LICENSE REQUIRED 100% ROAD LEGAL!

"Legal to ride in the UK in 200W 15mph mode from the age of just 14 upwards with no need for a driving license, insurance, MOT, road tax or number plate"
"15mph Restricted for on road use 25mph derestricted for
OFF ROAD USE ONLY*** "

from http://www.ebay.co.uk/itm/48V-20Ah-ELECTRIC-PEDAL-SCOOTER-MOPED-BIKE-SUPERB-RANGE-PERFORMANCE-/261626166797?pt=UK_Motorcycles&hash=item3cea227e0d

The letter of the law is getting very stretched, even with commercial advertising in th UK.

Hence my hope that although my tiny little Q100H hub motor is "250-350watts", it's far less blatant than most.

 
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Kinninvie

Esteemed Pedelecer
Oct 5, 2013
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Teesdale,England
My 2009 Chinese scooter is restricted to 15Mph but below the throttle is a 2 pin plug and when disconnected it will do 25Mph.
Of course this assumes that the wind is blowing hard enough in the right direction:eek:
 

Deere John

Esteemed Pedelecer
Apr 13, 2015
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Nice choice. Would you still recommend the Q100H 260rpm for a 700C bike? How about sound, is it quiet?

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