Electric kits for your own non electric bike?

[Mary Jane]

Hello.

I have a specialized mountain bike. It fits my frame very well indeed. My hubby has an electric machine and I fancy a bit of propulsion as well. (cant have him beating me home all the time )

I have managed to test drive an ezee torq as my brother owns one, but the frame wasnt large enough, and my foot kept kicking off the ignition key, (if you dont mind me saying, its is in a bad place) so I kept disengaging the battery with my heel. (a tad frustrating).

My own bike has a lot of miles beneath her, but as I love it so much, is there a possibility of building my own electric bike by adding a kit or such like to what I already own and love?

Any thoughts? And better still, any recommendations?


Mary Jane

 

[flecc]

Of course we don't mind you saying it Mary Jane, especially as you're absolutely right, it is a bad place for a key to stick out. I believe later models from eZee have their key modified to a less deep profile.

The obvious motor that springs to mind for a mountain bike is the Currie Electrodrive, often recommended for this purpose. It's an old design and a bit more noisy than newer motors, but is tried and tested. It normally uses old type lead acid batteries, so your heavy mountain bike will get much heavier yet, though you can opt for newer NiMh batteries at a price. Kits from Electrodrive costing from a bit over £300.

Alternatively, any of the front wheel hub motor kits will give you a newer design alternative, and electrodrive can also supply those.
.

 

[Ian]

Hello.:
my foot kept kicking off the ignition key, (if you dont mind me saying, its is in a bad place)

You're right Mary Jane, it is in a bad place. I broke one key by kicking it, then cut off the remaining keys to stop them sticking out.

 

[lectureral]

Mary Jane

I would recommend the Curry - I fitted it to my MTB and have been very happy. You can see the result here.

I like the fact that I am still riding my own bike. The kit is a bit of a fiddle to fit - mainly the motor to the back wheel and getting it all back in between the forks. I did it at my local bike shop and got some help - took about 1.5 hours total. It is a very strong hill-climber which was important to me and the weight (despite the lead acid batteries) has not been too much of a problem. I paid just a bit over £300 - bought it off eBay from Tony Castles - see eBay.co.uk: CURRIE ELECTRO-DRIVE ELECTRIC BIKE UPGRADE KIT (item 150119656113 end time 15-May-07 18:12:23 BST)

 

[allotmenteer]

Hello Mary Jane

I like the idea of a kit as you can get to keep your own bike. However be aware that in practice this may not always be the case. You should do a lot of research and ask a lot of questions to make sure a kit is suitable for your intended bike before purchasing.

For example, I have a rear hub motor kit from electricbikesales.co.uk which overall is a good kit but is one which I have had some problems with.
First off the rear hub motor only takes screw on type freewheels. This will limit you to 7 speeds, something like a 14-28 sprocket. This wll be a problem if you have a 8 or 9 speed freehub cassette on your bike (as on the bike I intended fitting it to).
Also the width of the hub motor is about 150mm so I had to bend the frame a bit. If your bike is aluminium (like my Marin) then I do not recommend bending it as it will probably damage it. I decided to buy a steel framed bike to fit the kit to. Of course being a cheap and nasty bike I don't expect it to last or be serviceable so I shall just run it into the ground and then I shall probably go for a ready-built electric bike or a kit which will 100% be suitable for my Marin.

Even when I got the motor to fit on the cheap bike I found that both a 6 and a 7 speed sprocket wouldn't fit as it fouled on the frame / had a really bad chainline. I could have bent the frame more but as the chainline was no good at all I decided to go to a 5 speed instead. I have found though that with the motor you don't really need so many gears anyway. I have even removed the front grip shifter and only have the throttle on the left hand handlebar.

I carry the battery in a pannier at the moment which is ok as the centre of gravity is low. Some kits have batteries on top of a rear rack which can affect handling badly. I certainly didn't like the weight up so high.
Eventually I hope to get round to making a bracket for the battery and fitting it to the downtube using the bottle holder.

Overall I have found that a kit can be a lot of work although they are a relatively inexpensive way to get into electric biking. Mind you I ended up buying a £79 cheapo bike and spending about £200 on various bits and pieces (including a new nimh battery) to get my bike up and running. After all the effort I am left with a fairly decent kit on a rubbish bike which was not really my intention when I set out. Ah well, when I've done 6000 miles on the bike (instead of using the car) the kit shall have earned it's keep.

If I was to start again I would most likely go for a Torq or one of the new 50cycles bikes. I really don't have the time to faff around with kits.

Not trying to put you off a kit but just letting you know they can be tricky and a lot of hassle.

Paul

 

[Mary Jane]

Thanks

Thank you for your replies.

For now is a waiting game. My main reason for not thinking of a torq is that the frame size is too small. I get very uncomfortable on it. So keeping my specialized was a lovely thought.

I looked at a bike on ebay as well, but saw a photograph of a man who was just over 6ft on it and again.... he was too bent up. So thats another one to bite the dust.

So far the only ebike that the frame will be ok for me is the Tidalforce, but they a) dont sell them in UK, and b) I dont think theyr e made at all anymore!

Mary

 

[Ian]

I looked at a bike on ebay as well, but saw a photograph of a man who was just over 6ft on it and again.... he was too bent up. So thats another one to bite the dust.

Mary Jane,

One size is supposed to fit all and yet people at either end of "average" seem to have difficulties, there are however things that can be done. A micro adjustable seat post will allow a bit more fore and aft adjustment of the saddle, a longer seat post would give more height if there is insufficient adjustment, a longer handlebar stem would give a longer reach and a steerer extension could be used to raise the handlebar height.

I had the opposite problem with my Torq, the bike was initially a bit big for my 5'6'' height, but an alternative seat post and an adjustment to the stem sorted things.

Ian.

 

[Canadian Cadence]

I feel I have to ring in here and recommend the Bionx 350 kit.
It does not have any of the disadvantages of most kits mentioned above.
It is an expensive kit but with 4 levels of assist and the throttle coupled with the strong unique hub drive and the regenerative modes and braking it is a real winner.
I am really looking forward to the results extra energy is about to post on the Bionx ( I hope they are testing a 350 and not a 250 ) and how it stacks up to the other bikes out there. I know that I have not found its equal yet.

I think the cost( to the UK) would be below the cost of a Torq and you would be using a bike that you are comfortable on. Here is some info on the 350 electric motor and battery electric bike conversion kit

 

[coops]

Torq too small?!

Hi Mary Jane

Just to add to Canadian Cadence's post, on pedelecs there's an excellent long review of the Bionx PL-350 kit by Nick, and also 2 shorter Bionx reviews , one a summary by Nick too.

I think this is the first time I've heard of a Torq being too small!! I'm curious to know if there is a height difference between you and your brother, and if the Torq was adjusted for you when you tried it: was the saddle position (both height and forward/rear adjustment) and handlebar elevation & forward/rear position adjusted at all? As Ian said, there are alterations which can improve the bike's fit, but those I mention are routine adjustments.

If you hadn't done so, try simply adjusting the saddle height so that you can just reach the ground with say the balls of your feet, and such that when you pedal your leg is almost fully extended on the downstroke, and see if that helps: don't worry about the key catching for now & if you want to try out the motor power, just switch the pedelec mode (on the battery meter, right hand side of handlebars) so that motor is on when throttle is turned even if you don't pedal. Just be sure to switch it back off when you stop or dismount, since inadvertently turning the throttle (its so easily done) may send the bike shooting forwards .

If I'm barking up the wrong tree I apologize, but just want for you to be sure its too small for you. I'm 6ft, & fairly big feet too, and my Torq's keys have the lower profile flecc stated, they are like a T with a slightly rounded top, and I've happily not had a single foot catching incident - I think the design now works very well in that regard.

If you still want to convert your existing bike, which I'd also initially wanted to do, I think the hardest design issue to overcome, other than finding a hub motor to fit your front/rear forks width without bending the frame, is where to put the 4 or 5kg of battery weight (normal for a 36V motor & ~20-30mile range) on the frame safely (i.e. not making the bike unstable or overstressing the frame) and securely (theft protected, for one: many custom made electric bikes batteries are "locked" into the frame when you turn off the power and remove the key). If you manage that, you still must decide how to control the motor: if you have front & rear derailleur gear changers on the handlebars, that would make it trickier to operate a twistgrip throttle while changing gear. You may want to alter your bike's gearing to make best use of the motor: legally you can do 15mph on motor only, but to match that speed on the pedals may require changing front chainwheel &/or rear freewheel/derailleur mech & chain length adjustment/replacement: so some new parts & tools may be required and many decisions may need to be made, as you see.

I think its fair to say that, once you've fitted a kit to your well-loved bike, then it won't be exactly the same bike anymore! for one thing, it'll weigh a minimum of 7-8kg more, and have lots of wires & new bits it never had before!

I gave up before I got to that stage, and just got a purpose-made electric bike . I hope some of all that helps you choose - good luck, and please don't be put off by what I said: it's a lot of fun to ride an electric bike & a good way to get around too .

Which bike does you husband have, out of interest? and do you think you could cycle ok on that?