Electric Bikes

Budget motor trials

I understand that £1000+ for an electric bike kit is a lot of money, as some people have told me “That’s a lot of petrol” so would a kit around £500 be any good? I will be trying some over the coming winter, I don’t drive so hope it will help with cycling in the usual wind and rain, wish me luck and get in touch if you would like to know how it’s going.

Here we go (almost)

I ordered two kits, one 250w front hub motor with twist throttle and 10Ah LifePo4 battery (which I will be trying this spring) and a 500w rear hub motor with thumb throttle and 15Ah LifePo4 battery, the kits had not been dispatched after a week of placing the online order (29th October) and no communication had been received, when I emailed to ask when they would be sent I was told the batteries would need to be made before sending order (nothing on website about this) still with no communications the motors and accessories suddenly arrived mid November, again I emailed, to be told batteries are being tested and would be sent in the next couple of days, they arrived on the 25th, almost a month after placing the order.

Here we go

The first impression getting the motors out of the box is “that's a big wheel nut!” 21mm in fact, this is something else you will need to factor in to the weights you will be hauling a 21mm spanner, the second is “that’s a lot of wiring” it seems the cheaper the product the more loose wiring you get. The weights and prices for the kits are as follows:

500w rear hub - 6.6Kgs (including 6 speed freewheel)

15Ah battery - 5.5Kgs (5.2 including canvas bag)

500w controller, throttle and all that wiring 0.9Kgs

Cost not including rim/spokes/wheel build/ and carrier (for holding battery) £511

250w front hub - 4.4Kgs

10Ah battery - 3.5Kgs (5.2 including canvas bag)

250w controller/throttle and all that wiring again 0.7Kgs

Cost not including rim/spokes/wheel build and carrier (for holding battery) £445

I built the rear hub into my rim, the spoke holes in the hub are way bigger than they should be at 3.5mm!! so I recommend using 13g spokes and spoke washers, now the fun begins as you start hitting problems, the width this hub was spaced to was 145mm my dropout were 130mm (not uncommon for 6 speed bikes), I reduced the left side spacer by 5mm, there was no tolerance for doing the same on the drive side, and spread my frame to 140mm, easily done with my steel frame but not so good on aluminium frames, next the tab washers where too chunky to fit in the dropout slots so filed to suit, with the wheel in I fitted the throttle and connected everything up, next job reset the gears, this should have been straightforward as it was originally a six speed but I could not get the chain onto the lowest sprocket as the gear mech hits the hub, this problem is not down to the bike, I have tried the wheel in other six speed bikes with a variety of gear mechs (short and long cage) and it is not possible to fit a spacer behind the freewheel as there is no tolerance to increase the spacers on the axle (with the narrow heavy hub, dishing the wheel is not something I would recommend) options are to set the gears to use just five gears (missing the lowest gear which you will need when the power runs out!) or fit a five speed freewheel allowing you to fit spacers and therefore use of the lowest gear sprocket.

First impressions on trying are it is a quiet motor with good power yes this motor is not for use on the roads being over the 250w (continuous) output but I wanted to see if the claims manufacturers make about these motors are true (ie. speeds of over 20mph), well not quite, the unassisted speed was 18mph so with a little rider input 20mph is easily achieved, but above this it is not efficient due to the increased rolling mass weight. The canvas bag holding the battery is not made to measure (they are the same size no matter which battery you order) and I found that because there are no internal straps to hold the battery in place it moved to the point where it would start coming off the side of the carrier that it was attached to, for the remainder of my trial I placed the battery and controller in a pannier. The system soon developed a fault of losing all power, the only way to rectify was to disconnect the battery lead and reconnect, it has been a random fault during my 1000 mile trial mainly when using the 15Ah battery so for the battery performance trials they are based on the 10Ah battery, they are also conservative figures, firstly, because I don’t want to kid you this bike is hard work to use without the assistance, an extra total weight of 10kgs might not sound a lot but it made the bike very sluggish on anything but the flattest road , and secondly I always used maximum throttle, on the throttle there are three lights indicating full (green) half (amber) and empty (red) which are not very accurate to the point that once the green light has extinguished the range and hill climbing capacity is poor, and well beyond the half way point, so with care and using the full capacity range could be extended, the 10Ah battery range was:

Unassisted range 15 miles

Assisted range 20 miles

Overall Impression

You might be disappointed with some of the quality, like the paint flaking off the hub almost immediately, and the cheap wiring connections that occasionally separate but it does the job at a reasonable price and apart from the cutting out problem I had which the company says can be rectified with a higher rated BMS (battery management system) of which I am still waiting for, the unit performed well in the extreme winter conditions and was very useful hauling heavy loads in my trailer that a 250w motor would struggle with (something those European bureaucrats that determine the legal limits of these motors don’t understand) the best point is they make a bike that is not obviously electric or expensive, would you be happy leaving your £1500+ electric bike around town?. The most frustrating part of this trial was dealing with the supplier and if you wanted me to supply one of these motors you would need to be patient as they only work at one speed.... slow!