UK newbie needs advice on 1st Ebike Build.

[loxster]

Firstly let me say a big Hi to all of you on this fantastic forum, I stumbled upon you whilst on holiday 10 days ago ( on my daughters I pad when I could get my hands on it lol).

I've been wanting to build some kind of E-bike for a while now but never knew where to go for information, help and advice until I discovered you knowledgeable guys on here.

I've had a quick flick through some of the posts and looked at your pics of " before and after" and I must say I am Very impressed but still none the wiser lol!

Some of the posts are from a few years ago and I know the technology changes rapidly so any help/advice on the latest kit will be invaluable.

My original idea was to add a front 500w motor/battery kit off ebay (Chinese dealers and plug and play so to speak) to my Boardman Team Hybrid, but after researching on here it sounds like a Steel fork is a "must have" (my bike as a full carbon fork and tapered steerer) so I have decided to sell this bike and am now looking for ideas on a suitable candidate ( my idea was to source a GT mountain bike off Ebay around £300)

Any other suggestions welcome.

My criteria are these:

A) I am 6ft tall and 190lbs if this helps.
B) I would like to pedal as well as have the ability to use a throttle when I''m feeling lazy
C) My daily commute is aprox 9 miles each way with one good hill of about 500 metres.
D) My thoughts are at least 1000w motor , 48v lifepo4 20 Ah battery , Controller?? No idea as I don't even know what this is (told you I was a newbie lol )
E) I would like to mount the battery in the triangle of the frame to even out the weight.
F) Use a twist throttle.
G) can you get 48v bottle type batteries? Seen 36v 9 Ah ones on Ebay.co.uk and like the stealthy looks of these.
H) Budget of around £750 ( this is for the Electric side of the bike and not including the bike) I know a lot of vendors on Ebay use US$ so whatever £750 is in dollars.

Have I missed anything?

I'm hoping some of you guys will spare me your precious time and knowledge and help me to achieve my goal ( the wife thinks I'm having a mid-life crisis lol.)

Thanks in advance Jay. :wink:

 

[dogman dan]

A typical 36v direct drive motor kit will suit your needs just fine. But these medium powerful kits have 22 amps controllers, and run best on 15 ah of battery. They will put a lot of strain on the little 9ah bottles. Those are for use with the small, low wattage gearmotors, that come with 12-15 amps controllers.

Running the 36v kits on 48v works fine. A 48v 15 ah battery will get you more speed and power, producing 1200w under max load. You'd have about 20 miles of range, at speeds of 25-27 mph.

Those GT's make good ebikes. But so will your existing bike for rear motor, if it's a 7 speed gear on the rear wheel.

 

[loxster]

Thank you Dogman for your reply.

Just been looking on Ebay.co.uk and I've found a dealer in china who will do me a 48v 1000watt rear wheel kit with 48v20ah li-on battery for £569 delivered, Is this a good price?

Reading on here... Aren't li-on batteries dangerous (catch fire etc) the wife will be really annoyed if I burn the house down

If someone could take a look at the item and let me know their thoughts i'd be grateful, item no' is 151077091470 on Ebay.co.uk.

After a few emails to and from each other he made me the above offer but I don't know enough about these things to know if the quality of the parts are any good so all advice is welcome.

Think i'll be going with a good quality mountain bike as my base bike, been looking and there are a few good steel bikes on Ebay with quality suspension forks and decent specked parts which should be within my budget, Steel bikes are supposed to ride a bit smoother than Aluminium due to their flexing properties..is this correct? .

Getting itchey fingers and can't wait to get the ball waiting so please let me know your thoughts on what to get.

Many thanks Jay.

 

[d8veh]

Just in case you don't know, it's illegal to us that stuff in the UK. The limit's 250w and 15 mph. If you want to go over that, you best build something stealthy, which means something like a 500w geared motor and concealed batteries, or maybe one of the new Bafang crank-drives.

 

[CogHog]

Most of the bikes on this forum are illegal and in the USA we do have a 750w max. My buddy is putting bikes together in Ireland and can supply you with a ride on his bike. Also sell you any option you need like a laced rim with motor or just a motor and spokes. Controllers, batteries. He's about 230 miles miles NE of you. Does not hurt to chat. Should be starting up the business soon. PM me if you need his email. I will copy this post to his email and he may PM you.

Robert

https://www.facebook.com/boostbikes.keith?fref=ts

 

[loxster]

Hi,

Thanks for that, I would be interested to see what ideas/ prices he has to offer me.

If you could ask him to get in touch through this forum i'd be grateful.

Many thanks Jay.

 

[dogman dan]

Perhaps I should have pointed that out, about the 250 w limit. Much will depend on how you ride, do the cops already hate you, and the general attitude in your locality. Many can ride illegally powerful bikes with no problems. Other towns have some jerk cop who lives to pull over ebikes.

Once in a while, we get a guy who just can't understand why cops keep pulling him over. He's on that bike, because of all the DUI's or drunk in public busts.

Most of the lithium battery fires involve the Lithium Cobalt chemistry. Chances are, your choice is Lithium Manganese. Nevertheless, do take some basic precautions. Charge outside if convenient. If you must charge inside, at least don't lean the bike on the curtains while you charge it. Try to give a charger room to spark without starting the room on fire. So don't place the charger on a pile of old newspapers.

A steel bike with a rear hubmotor is a very good combination for your first ebike. If you get one with 1 1/8 headset, you will also be able to upgrade to better shock forks in the future if you like.

The other decent bike for the first try is a beach cruiser with v brakes and 7 speed rear gears. It can take either front or rear hubmotors with ease.

Really cheap alloy frames do feel like the cheap turds they are. A cheap steel bike generally lacks that floppy feel from side to side. The cheap alloy frames flex like crazy. But a really good quality alloy frame will feel good. The really nice thing about steel bikes for the first try, is that they are very forgiving. You can weld on them if you need to, or bend the dropouts wider if you need to.

 

[friendly1uk]

It sounds like your already a keen cyclist. Are you wanting to do 20mph effortlessly, Or are you looking for a moped?
I think without full suspension 20mph is probably enough. Upper 20s if you have big soft tyres. If you want to do 30mph your carrying a lot of kinetic energy and should also wear a motorbike helmet. It is hard to know where too draw the line though.
20mph gets you places while still feeling like a cyclist. More importantly you still look like a cyclist, which is good from a legal point of view. It is also good for safety. Motorists don't assess the speed a cyclist is approaching, they just look at distance and go for the gap, based on a bikes typical speed. When your doing 20mph vehicles will often try to overtake you just because your a bike, then fail and pull in behind again. It is a dangerous game going fast on a cycle while sitting comfortably.
Most motors will make it to 20mph, but a mini motor with a 20mph headwind might be quite useless. Especially up a 500m long hill. You would have to run realistic power levels or it would burn. This legal stuff probably won't cut it for you. A 500w geared motor seems like a better proposition. I run one at 15 amps, which a bottle battery might supply. I do 8 miles regularly with a 5ah pack, using between 3 and 4 ah and I'm a couch potato. I could put the same power in to a 250w mini motor, but it would cook too easily. Just being bigger offers better torque and better heat dispersal. It is 4.5kg though. Least a geared hub offers no resistance to pedaling though if you have too.

 

[loxster]

Hi,
Thanks for the replies and advice so far.

I am a keen cyclist ( when time permits) and I do commute to work(on my hybrid) and do the local trail centre on my Canyon nerve AL29er so I do have a bit of fitness, I can maintain 19-20 miles per hour on flat roads and have span out in top gear when the terrain allows so I am already capable of breaking the 15mph speed limit that the UK is limited to.

My goal here is to create a bike that will propel me in the mid 20's mph with me pedalling so to make any commute I do feel like i'm only using 50% effort if that makes sense, But if the situation allows i'd like the capability to do 30mph without pedalling.
Basically to speed my commuting up whilst reducing the effort I expel.

I don't know if this bike is known to many people on this forum but i'm about to bid on a Voodoo Wanga steel mountain bike (Ebay uk),
It comes with Roxshox Reba forks , Sram X9 drivetrain and Avid elixir cr disc brakes ( fairly decent spec) so i'm guessing this would make a good base bike for my project ..Any opinions?

So considering my speed and distance requirements would 1000w 48v motor and 48v lifepo4 20AH be sufficient or overkill?

Thanks in advance for any advice.

 

[CogHog]

The 9 pound weight BMC Torque motor at 48v will fit that bill. I ride slow and pedal to save battery and get 19 watt hour per mile. Or go 30 mph no peddling and get 33whpm. And I can carry my bike up to my second floor apartment every day after work and I am 60 now. Speed is there when you need it to merge through traffic. I will tell Keith to call on you here.

 

[MadRhino]

Build on the rear, use a slow motor in that 29er wheel.
Buy the biggest tires that will clear the frame.
Doesn't hurt to be illegal if you build stealth and behave wisely.

 

[Drunkskunk]

I've heard of the Voodoo Wanga. It has a reputation for the worst paint on any bike, But otherwise a great frame. MTBR gives it some good reviews: http://www.mtbr.com/cat/bikes/xc-hardtail/voodoo/wanga/prd_365008_1527crx.aspx
The one thing you'll want to be sure of, is the rear gearing, More than a 7 speed cluster on the rear will make fitting a rear hub motor a problem.

Since you enjoy pedaling, you may prefer a geared hub that will freewheel when you're not runing the motor. An 8T MAC (BMC clone) should exceed your needs at 48V, but a 10T will be better if you have any steep hills to conquer, although a little slower.

http://em3ev.com/store/index.php?route=product/product&path=36&product_id=107

 

[footloose]

Jay --
My weight, route, and desired pedalling-vs-throttle proflle seem similar to yours.
I build a bike using components from EM3ev (Mac 10T, 48v / 12Ah battery, 9 FET controller).
Used 26" rather than 29" wheels, but believe it would still do very well with larger wheels.
Would offer you a test ride, but our respective locations might make it difficult :wink:
My experience, if it helps:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=50664

 

[loxster]

Hi all,
Before spending money on a different bike I was wondering what the general opinion would be on using my existing bike ( Boardman Team Hybrid) as the base bike for my project.
If you would be kind enough to google images on it and take a look at the frame etc to see if it would be safe/ strong enough and let me know if there are any issues with it I would be grateful.

Just for info perposes it weighs 10 kg and has a full carbon fork!
It as 10 speed SRAM apex rear mech and X5 10 speed shifters, would I have to swap these to a 7 speed set up ?

All replies welcomed, thanks Jay

 

[d8veh]

You really need a light-weight build with that Boardman. Also, you need a cassette motor otherwise you'll spoil your nice gears. There's three relatively cheap cassette motors:
1. The Q140 comes in two different speed versions 201 rpm and 328 rpm. One is a bit too slow and the other a bit too fast.
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2013-85-BG4T.8Y0YY
Have a look at Chas's build, which explains the speed problem
https://www.endless-sphere.com/forums/viewtopic.php?f=3&t=49691&start=25

2. The MXUS MX04 is a bit bigger and can handle more power. It has a bit more torque than the Q100/140. It's 270rpm, so will assist to about 24 mph. It has good power up to about 21 mph but then it tails off to its maximum. I've got a couple of these that I'm selling on Ebay.
http://www.ebay.co.uk/itm/181216589468?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

3. The Bafang CT comes in a couple of power versions, but they're the same size and weight, so no point in getting the lower power one. The 500w one at 36v is also 270 rpm, but has more torque than the MXUS, so will accelerate briskly to about 22mph and then topping out at about 25 mph.
http://www.bmsbattery.com/ebike-kits/589-q11-48v1kw-front-driving-hub-motor-e-bike-conversion-kit.html

All the above speeds are for a 700c wheel. They'll be slower in a 26" wheel.


The bigger the motor you get, the bigger the battery needed. A big battery will spoil that bike. If you want a big battery high power solution, it would be better to get a cheaper stronger bike. It's not that your Boardman can't take it. It's just wasting everything that's good about that bike.

Here's some lightweight batteries that can give good current for higher power. I haven't tried one yet, but at least the cells should be good:
http://www.aliexpress.com/wholesale?SearchText=36v+11.6+panasonic&initiative_id=SB_20130911145949

If you want to use pedal assist, it's best to get a controller with a LCD display so that you can set the level. Without the display, most controllers give full power when you pedal, which is not what you want.

 

[loxster]

Hi Again,

Phase 1 of my project is now complete... the base bike.

Just won a GT Aggressor XCR (2010) model on Ebay, The guy says it's in great condition and needs nothing.
Spec is....140mm Marzochi bomber 15mm through axle fork ,shimano deore and xt components, Wheels nothing special so I will upgrade the front one to a stronger one( maybe a downhill strength one).
If you would be kind enough to google this bike and take a look, Feel free to give any good/bad points and let me know of any problems you can foresee with it i'd be grateful.

One question I have is, Do I need to use the brake levers that have a cut off switch built in or could I have a separate cut off switch mounted on the bars in case of emergency?

Now the fun/ nightmare ( delete as applicable) really starts.....What motor, controller, bms , battery etc etc to get.

The bike is a 26" wheel version so if any one could recommend me any of the above and let me know where to get them from it would really help.

Thanks Again.

 

[d8veh]

If you want to use PAS, brake cut-offs are essential, otherwise advisable.Before deciding on a motor, you need a clear vision about how fast you want to go, how far and how much pedalling you want to do. If you're happy with 22 mph, A Bafang 500w CST will go very nicely with it. You'll be able to use your nice cassette gears without having to downgrade to crappy free-wheel gears. It'll have more than enough power for what you want. It's smooth, quiet and relatively light. You could use a high power bottle battery that will have enough range to do your return trip - more if you pedal. It has to be the high discharge one like the one below. Total outlay about £600 including shipping and duty. Here's your shopping list. You have to decide which throttle you want, but the small plain thumb throttles are most likely to fit. You might want to get two or three different ones in case of fitting problems:
http://www.aliexpress.com/item/36V-WaterBottle-E-bike-battery-Panasonic-cell-NCR18650/902910322.html
http://www.bmsbattery.com/ebike-kits/589-q11-48v1kw-front-driving-hub-motor-e-bike-conversion-kit.html
http://www.bmsbattery.com/36v/450-a-pair-of-ebike-torque-arm.html
http://www.bmsbattery.com/controller/548-s-led770-e-bike-led-meter.html
http://www.bmsbattery.com/controller/550-s-led770-e-bike-led-meter.html
http://www.bmsbattery.com/ebike-parts/570-pas-pulse-padel-assistant-sensor.html
http://www.bmsbattery.com/controller/552-s06-250w-imitation-torque-square-wave-controller.html
http://www.ebay.co.uk/itm/SUPER-LARGE-electric-bike-plastic-controller-case-box-200-100-70mm-for-24-72v-/130979104643?pt=UK_Bikes_GL&hash=item1e7ef68783

Get one or two of their spoke keys as well. It'll save a lot of both later, and they only cost $1.

 

[loxster]

Thank you D8VEH for taking the time to go through and search me out a shopping list of parts but and it's a big but, I really want the top speed to be somewhere around the 30's mph and not low 20's so would I have to step up to 48v and 1000watt to achieve this??
It's a shame they cannot do a 48v battery in the bottle shapes because I think that looks really good and keeps weight central ish on the bike.
If I'm being honest aswell, I'd like to have enough range to do at least 20-30 miles on one charge at a decent speed , would the list you gave me do that??
Rice wise you came on under budget and it would look stealthy to the untrained eyes so I commend you on that but I can't help thinking ( in my inexperienced mind) that I would have regrets not going for a more powerful system from the start.
This really is a one time only deal( so the wife tells me) so I want to get it right first time if possible.
Once again many thanks for taking the time out to look for me and if possible I look forward to any more reccomendations you may have.

 

[friendly1uk]

You could put the 500w CST with a 48v 12Ah frog box and see 30mph. At a more realistic 20mph you should see over 20 miles. You might see 50 just pottering along. At 30mph your not really getting very far though.

The frog box is useful. The part that stays on the bike can house a 6fet controller. These give 15amps which is ok for a cst with 44.4v and equates to about 26mph with no pedal effort. You would need a modified one for 48v performance. Perhaps just a 17 amp shunt mod. I need to look at this too, as it's possible that the fet's can just be swapped for better one's with no other modification to the board. It won't turn up the power, but it means that you can turn it up more when you do. Bridging the gap between the 6fet and 9fets 22 amp performance. It is a tidy controller the 6fet, with no heat issue's in our climate. It also has a frame box designed for it. Like a sunglasses box with a couple of tube straps along one edge. The controller doesn't quite cut it for you in it's standard form though. Even the capacitors might need swapping once you look inside. Someone might mod one for you though, if you thought it worthwhile.

On the other hand, this frog is 3.26kg in about the worst place possible.

I'm just doing the math. That frog spec is too light. You would still want it in the frame though.



I use rc lipo. A 48v 5Ah battery might weigh 1.6kg and the bms and connectors another 100g. That should get 10 miles at 20mph. I regularly do a 7.5 mile run on 3Ah doing appropriate speeds up to 27mph. Then I take a half mile detour coming back, and use 2.8Ah. Only about 2 miles of each leg can be done at high speed. The rest is varied, but 20mph is my target speed along open boulevards. Any faster and you are deafened by wind noise and a lot of people will pull out too late. Women can't do objects in space. They know how far away something should look before pulling out. Based on there near miss score sheet. A trial and error thing, like 'if it's not past the bus stop, I can go' What they can't do, so don't try to do, is judge your speed. If they look twice you have a better chance, but on the whole many just pull out. I had one today while I was doing around 20, She at least left the bike lane free so I could undertake her. Then she was very hesitant to pass me. Probably expecting me to hurl abuse. I didn't even look though, It is just part of riding.

 

[d8veh]

Thank you D8VEH for taking the time to go through and search me out a shopping list of parts but and it's a big but, I really want the top speed to be somewhere around the 30's mph and not low 20's so would I have to step up to 48v and 1000watt to achieve this??
It's a shame they cannot do a 48v battery in the bottle shapes because I think that looks really good and keeps weight central ish on the bike.
If I'm being honest aswell, I'd like to have enough range to do at least 20-30 miles on one charge at a decent speed , would the list you gave me do that??
Rice wise you came on under budget and it would look stealthy to the untrained eyes so I commend you on that but I can't help thinking ( in my inexperienced mind) that I would have regrets not going for a more powerful system from the start.
This really is a one time only deal( so the wife tells me) so I want to get it right first time if possible.
Once again many thanks for taking the time out to look for me and if possible I look forward to any more reccomendations you may have.

This one has recently been posted on our UK forum.
http://www.pedelecs.co.uk/forum/classifieds/15716-cube-bafang-55-5v-lipo-30mph.html
Sacko builds some nice bikes and knows what he's doing, not like the lash-ups you see on Ebay. You'll note that he says it does 12 to 15 miles at 30 mph. To do 20 miles, you need substantially more batteries.

From my own experience, doing any more than 25 mph on a bicycle on UK roads is not very pleasant. Brakes, tyres and suspension are all on their limit. Cars and trucks don't see the speed: They just see a bicycle, so they just pull out on you as if you're not there. If you have an accident, there's no disguising a massive battery pack and motor, and a bike that looks like an electric motorcycle. Also, you have to spend your whole time looking out for cops and feeling guilty. Doing 30mph sounds like a bit of fun, and indeed it is for a short blast, but unless you build a bike with wide rims and tyres and proper suspension, you'll soon find it stressful.

Don't get me wrong, I'm not against 30mph in any way. Neither am I any sort of wuss. I also ride sports motorcycles (normally flat-out). I've built my own 30 mph bicycles, so I'm just passing on my experience. If you want 30mph, a motorcycle (electric or IC) does it much better and cheaper with no risk of losing your licence.

 

[knighty]

UK here too (Sunderland)

just wanted to say I do 40mph everywhere on one of my bikes and no-one every bothers me

I got a 1000watt 48v kit on ebay, a 72v 10ah battery from bms battery, and then a 72 controller on ebay

how good are you with electrics ? - it could well be worth buying yourself some cells/bms (battery management system) and connecting it up yourself, that way you fit them to whatever shape you want

I don't have a lot of faith in those bottle batteries at all :-o

 

[loxster]

Hi,

After giving it some serious thought and seeing some of the builds others have created my thinking is to go down the stealthy smaller is better route, I'd like to create a minimalist build that looks discreet and would be fairly light.

My thinking after reading some of your replies is that maybe I would be better off going for something that will comfortably do 20-25mph with me assisting as I still want a workout and don't really want to create a moped if you know what I mean.

After looking at various builds I don't really want a great big hulking battery on the bike and simplicity would be key for me with my "no knowledge" ebike building back ground.

I really like the look of this bike I found on Ebay uk..Item number 151109855526 , Shame they don't do a more powerful version as I think it looks fantastic and very minimalist, Love the bottle battery style and small hub motor .

If any one knows of any kit that would match the looks of this but out perform it and would be easy to put together please let me know what and where to source it from please.

Dehv8, You have some pics on the pedelec forum and one of your bikes features a system very similar to this, looks great but i'm guessing it will be too slow for my requirements?

Thanks for all input so far.

 

[d8veh]

If you're talking about the Oxydrive kit, it can assist as high as 24 mph, but it's relatively low power, so you only get that speed if you're light and pedal hard. 250w will give you an average speed of 12 to 18 mph depending how hard you pedal. A headwind will slow you right down. Here's another one I built, that's still relatively light at about 23 kg IIRC. It pulls hard to about 21 mph, and with light pedalling, it'll cruise at about 22mph, topping out at about 24 mph.

http://www.ebay.co.uk/itm/Electric-bike-goes-up-steep-hills-very-long-range-GPS-tracker-fitted-excellent-/141062344572?pt=UK_Bikes_GL&hash=item20d7f88f7c

 

[dogman dan]

Have a look at this website, of a vendor many of us on ES trust. The 10T Mac kit is very popular. It will seem to disappear behind the freewheel and the brake disk on the rear. You should see 30 mph or very close to it, with 48v.

Definitely rear motor with that fork. It's a through hub, so not compatible with motor kits at all.

48v 20 ah is very large and heavy, 48v 15 ah will carry a lot nicer. EM3ev's triangle bag and battery works great if your bike has a triangle.

You don't need brake cutoffs, those are really a legacy from brushed controllers that often failed in full throttle mode. Brushless controllers don't really need them.

But your 9 speed shifter will not play well with a 7 speed freewheel. So you may have to rig something for that. The simplest might be an old fashion bar mounted shift lever, or a new brake and shifter in 7 speed. Your chain will be too narrow too.

 

[dogman dan]

Googling what might be similar to the bike you bought, it looks good for the triangle battery bag. So get a battery that will fit in one, if you don't buy EM3ev's battery too.

It's the best way to carry a battery in the triangle I've found yet. VERY good product. Make sure what you buy for a battery will fit in that bag.