The eBike thread

Bigus

Guards won’t be one bit bothered unless you’re completely acting the eejit.

unkel

Bigus wrote: »

Guards won’t be one bit bothered unless you’re completely acting the eejit.

Still a 250W sticker on a motor that can easily do 1,250W might help

SlowBlowin

I have a question, has anyone built an eBike with batteries in panniers ? Surely Madlad/Unkel on some prototype bike ?

If you have what were the effects on handling, any other downsides apart from wiring ?

Nothing serious, just settling a pub argument with a friend/idiot who said 6 leaf batteries in panniers was the way he would go. Could you really go round a corner with 25kg of battery flapping round the rear wheel ?

SlowBlowin

SlowBlowin wrote: »

I have a question, has anyone built an eBike with batteries in panniers ? Surely Madlad/Unkel on some prototype bike ?

If you have what were the effects on handling, any other downsides apart from wiring ?

Nothing serious, just settling a pub argument with a friend/idiot who said 6 leaf batteries in panniers was the way he would go. Could you really go round a corner with 25kg of battery flapping round the rear wheel ?

Never used panniers for batteries but used one of these and it worked great.

I had 66 v 10 ah of lipo in it and had plenty of space, i had it mounted on a seat post rack, really convenient as it was super easy to put on and take off.

https://www.topeak.com/global/en/products/rear-rack-bags/857-mtx-trunkbag-dx

unkel

Very slick, but that bag costs almost as much as my 59V 12Ah battery

Any details of how you connected it to your saddle? That bike must have been very rear heavy with motor, battery and controller all weighing all the way back on the rear axle

unkel

unkel wrote: »

Very slick, but that bag costs almost as much as my 59V 12Ah battery

Yeah but it was very convenient and I could store more than just the battery in it.

I really miss that bike because it had so much power, could do 60 Km/hr easily and it was easier to pedal without power than my Bosch bike , when my legs got tired on hills I could press the throttle and give my legs a rest, not so with the legal crank driven bikes and the Bosch makes you work hard, my old Bosch has only 50 Nm of torque , sure a lot better than nothing but not as good as having 160 lol.

I was pulling about 3,5 Kw from the battery with the above setup it was a lot of fun

I was running 5.5 Kw ( from the battery ) with a direct drive hub at one stage, peak power was a lot more, the acceleration was mental and of course having no gears to change meant I got all the smoothness and continuous power a hub provides. Those were the days....... Only Lipo can do that kind of power !

Joe1919

SlowBlowin wrote: »

I have a question, has anyone built an eBike with batteries in panniers ? Surely Madlad/Unkel on some prototype bike ?

If you have what were the effects on handling, any other downsides apart from wiring ?

Nothing serious, just settling a pub argument with a friend/idiot who said 6 leaf batteries in panniers was the way he would go. Could you really go round a corner with 25kg of battery flapping round the rear wheel ?

It depends on the weight. Here is my personal experience. At one point, I had a two 36v batteries (9ah + 11ah ) fitted in a pannier bag (with some extra bungi straps for security/stability) and a steel strong pannier battery rack. The setup was secure and strong but was heavy, with rack about 2.5kg and batteries weighing over 6 kg, giving an overall weight of over 8.5 kg, and worst again, the center of gravity of weight was far back behind the rear axle, as I needed the foot clearance. Worst again, the bike was a rear hub driven bike (motor and controller extra weight about 3 kg). Anyhow, the bike was definitely very heavy at the back and a bit unstable, and hard to handle with basically an extra 11 -12 kg in the rear. I had also a problem with rear spokes breaking every approx 200 miles.
Last winter, I decided to tidy this arrangement up by fitting a lighter (less than 1 kg ) alloy rack and using a lighter battery (with higher density 3.5 ah cells), reducing the weight by over 3kg and it made a difference. (older batteries had heavier 2.2 cells) I was also able to get the remaining weight more forward on the rack.
Anyhow, from my experience, if the batteries and rack are light, its ok but can become a problem if battery is heavy. Rack batteries work better on front hub motors, and are often used with low step (unisex/ladies type).

Spokes won't break if the rim and spokes are the proper spec for the job, I never had a problem with spokes even running 5+ kw, I never had an issue with the heavy duty rim and spokes supplied with em3ev mac 8T motor and into that I was pulling 3.5 Kw. Had no issue with other hubs either.

If spokes are breaking then this is a bad quality kit.

The rear of a hub bike is heavy but I found once used to it it was fine, for normal cycling I'd still prefer the powerful geared hub setup above over crank drive. The only think with rear hubs with power is that torque arms are essential.

For slow steep trails chain drive is king, we don't have many if any trails in Ireland anyway that would require such a setup and I'm not too sure Farmers would be too Keen if I were to cross their land on a Ebike ?

Are there any laws against this does anyone think ? considering crossing farmland is not so big a deal these days, didn't they relax laws or something to do with insurance to make crossing farmland a non issue and perfectly legal ?

unkel

Deleted User wrote: »

Cool looking forward to some pics and motor review.

First good ride with the dog this morning. Hooked up my 14S3P Vruzend kit 52V nominal battery pack freshly charged to 58.8V

Max speed 30km/h on throttle alone with me sitting up straight. Pulling over 1030W from the battery during initial acceleration. Not bad for a strictly 250W (48V) motor

As expected with a geared hub motor, there isn't an awful lot of torque, so it will not pull me up a steep hill from standstill. Plenty of poke for everything else though. In case you are wondering, I was carrying the battery in a back pack

Tyres were put to 20PSI which is probably too much for a fat bike, even when riding almost exclusively on hard surfaces. Must bring that down to about 15PSI and try again

nokiatom

unkel wrote: »

First good ride with the dog this morning. Hooked up my 14S3P Vruzend kit 52V nominal battery pack freshly charged to 58.8V

Max speed 30km/h on throttle alone with me sitting up straight. Pulling over 1030W from the battery during initial acceleration. Not bad for a strictly 250W (48V) motor

As expected with a geared hub motor, there isn't an awful lot of torque, so it will not pull me up a steep hill from standstill. Plenty of poke for everything else though. In case you are wondering, I was carrying the battery in a back pack

Tyres were put to 20PSI which is probably too much for a fat bike, even when riding almost exclusively on hard surfaces. Must bring that down to about 15PSI and try again

Poor dog

unkel

unkel wrote: »

As expected with a geared hub motor, there isn't an awful lot of torque, so it will not pull me up a steep hill from standstill. Plenty of poke for everything else though. In case you are wondering, I was carrying the battery in a back pack

LOl I think you mean with that geared hub and power setup, Geared hubs have plenty of torque with the right motor , controller etc.

A MAc 8T was able to pull me up a 14% hill at 50 Km/hr 52 volts !

But looking good, a BBSHD would look the business on that bike.

unkel

nokiatom wrote: »

Poor dog

Maybe I should have explained (did I not do this already on this thread?), the hardware on the bike is just to get the dog safely via public roads to the park / canal, where there is no traffic and she goes off the lead.

The dog is a very muscular and fit Labrador, but as most of them, she tends to put on weight if not exercised enough. An occasional long run / hike (10k +) sorts that out. The daily 5k walk, even if brisk or long ball throwing / retrieve session, just doesn't cut it.

And for the record, she can't keep up at 30km/h for a few hundred meters, but she isn't far behind either!

BarryM

Is that a starting handle sticking out?

unkel

You mean the dog lead with spring bar???

John Hutton

unkel wrote: »

You mean the dog lead with spring bar???

Does that work well? I'd be worried about the dog dragging the bike over ha

unkel

John Hutton wrote: »

Does that work well? I'd be worried about the dog dragging the bike over ha

It works very well. The force of the dog giving the bike a big pull, is largely absorbed by the big spring. This contraption was sold as suitable for up to medium dogs. Labradors are a medium size breed and mine is female, so a good bit smaller and lighter than a male. But she is very strong and about 30kg, so about the max this can safely take. The fact that I'm over 100kg and the bike plus battery etc also well over 30kg helps for stability obviously

BarryM

unkel wrote: »

You mean the dog lead with spring bar???

Jaysus they think of everything.... I live in a remote area, the idea of a lead for a dog is alien.
We did have a guy around here who drove his cattle driving the hi-ace, with the stick out the window.....

Great idea:D

unkel

Made a decent profit on the turnaround of a fixer upper Velocifero scooter, so I've a Cannondale Bad Boy 4 2016 coming in this evening (EUR150 on adverts)



Linky


Looks like a good candidate for a mid motor setup :cool:

(I'm getting there, Mad_Lad, next up is your LiFePo4 batteries and a proper balance charger )

Can't justify going for the BBSHD because it offers very little above the BBS02B, which can output about the same power as a BBSHD with 48V if you use a 52V battery

I guess this is still the cheapest, shipped from the EU (so no taxes) at USD385 shipped (EUR344) including either the P750C or P850C colour display (which of these would be your preference - I need speed, wattage and voltage displayed at a minimum?)

Linky

John Hutton

I got the 750, seems good to me, it's neat.

unkel

Aye the BBS02B has a 25A continuous current controller (as opposed to the 30A controller of the BBSHD), but with a 52V battery fully charged (58.8V) that means it will be good for 1.5kW, which seems adequate to me

Only alternative setup I can think of is a 3kW direct drive rear wheel. This would need a 52V LiFePo4 battery and a minimum 60A (programmable) controller :cool:

I want to do both

loughside

unkel wrote: »

Can't justify going for the BBSHD because it offers very little above the BBS02B, which can output about the same power as a BBSHD with 48V if you use a 52V battery

NO! Totally different internal design.

I have both the BBS02 and the BBSHD... the HD is a long way ahead in terms of effortless torque, think 6-cylinder diesel Merc,

if you can stretch go for the HD

unkel

Couldn't justify it. EUR344 for the BBS02B and EUR598 for the BBSHD from the same site. Makes the BBSHD look very poor value for money at nearly twice the price!

If I had a long daily commute, needed to do it at the fastest possible speeds (>50km/h) continuously then maybe I could justify it (like samih) just for the sake of reliability (over powered, over engineered, better cooling) given the money savings you'd have over using public transport, a car or even a motorbike.

Joe1919

unkel wrote: »

For me anyhow, there is two ways to think about mid-drives. The first way is to think big and think heavy, with high power and controllers that take a heavy current and need a strong and heavy battery.
The second way is to think small, and light, with a lightweigh motor and controller that takes a modest maximum current (15amp) but with gears and perhaps a little pedaling to get you where your going.
Anyhow, if considering the second lightweight route, I would consider the 36V 350W TSDZ2 with throttle (optional) for 280 dollars. Of course, my decision would also be prejudiced by the fact that I have a good supply of 36v batteries but there is a 500w 15 amp 48v version for 300 dollars.
http://www.pswpower.com/ven.php?cargo.2018-4t-hkfj

PS good article on BBSHD
https://ebikechoices.com/bafang-bbs02-vs-bbshd/

unkel

Funny you are saying that, Joe1919. Turns out my new bike was not the 2016 model that was advertised (with 700 wheels) but the older 2014 model (with 650 wheels)

Got a bargain and should have checked before handing over the money, so I'm not gonna look for my money back. It ain't no keeper though. Can sell it on as is, or convert in the cheapest possible way (either hub or direct drive or even mid motor) and sell on

I've just sold my last 36V batteries (with the scooter) and was only going 52V from now on, so any 48V kits out there that are really cheap and will work with above bike?

While I continue my lookout for a full suspension or hard tail 29er with a large frame for a Bafang mid drive conversion...

unkel

At GBP109 including shipping to Parcel Motel, this is cheap.

Linky




I think it's just wheel (without tyre) plus controller. I have some spare throttles. No sign of any rear cassette though?

A geared hub is all you need in Lucan, unless going on long steep slow trails I wouldn't bother with the Mid Drive.

it would be interesting to see if your geared hub could take more power.

Not LiFeP04 batteries, go with LiPo, smaller and lighter than LifeP04, I just bought recently a LiFeP04 battery for my radios part because of the safer chemistry but also part because the voltage is spot on for the radios.

With LiPo you got the power to make any battery size you want, for instance I had 12S 10 Ah once with the 8T Mac just to give me a boost when out cycling, and it worked a treat, gave me tonnes of amps and around 50 Kph from a battery about the size of 2 large boxes of matches !

unkel

Deleted User wrote: »

it would be interesting to see if your geared hub could take more power.

It's rated for 250W and 48V. And I already measured 1030W (at 59V) out of it (well out of the battery)

You reckon I could send something like 2000W to it for bursts of say 20s-30s (on the flat)?

(I'm not gonna blame you if it goes up in schmoke LOL, just looking for your opinion based on your experience)

If you reckon that can be done, I will need to get myself a hefty (programmable) controller and some lipo batteries methinks...

What would you recommend?

Joe1919

unkel wrote: »

You reckon I could send something like 2000W to it for bursts of say 20s-30s (on the flat)?

The is a thing called 'core saturation' if you try to push too much current through a motor.i.e The motor iron laminates magnetically saturate and pushing more current only results in more heat. The motor you have (if I can remember) is fairly similar to the front mxus xf07, (2.8kg, 1:4.4 reduction ).It is a lot lighter than say the mac i.e. It has a lot less iron in its core. Having said that, I would google around, using the similar xf07 as a reference to see what its limits are.

unkel

If current is the issue, I can up the voltage. Just make a different battery and get a different controller (was planning to anyway). How does 72V * 30A sound? Would still give me well over 2kW

unkel

@Mad_Lad - if I should stick to 52V, are these lipo packs good value for money?

Linky


USD 140 for 2, so EUR125 for a 14S 5Ah pack, would need 4 for a 14S 10Ah pack (520Wh nominal) but will get 10% discount for being a first time buyer, that's EUR225 in total

Not cheap given that I have just bought 624Wh nominal of 18650 packs with built in BMS for just EUR100, although I do appreciate the oomph you can get out of these lipo batteries