another noob question

[PaulQwerty]

I have spent many months reading through this forum and would like to thank all the many excellent contributors to this forum.

Having visited and tried a couple of different ebikes available to buy in the UK I was left a little disappointed at the 250watt power which is the legal requirement in the UK. I weigh around 100kg and live in a very hilly area of East Devon in the UK and would like to sometimes tow a trailer with up to 100kg. I don't need huge range maybe 10-15 miles between charges hence finding my way to this wonderful resource of knowledge.

These are my thoughts so far, all comments welcome.

Bike - I would like a full suspension mountain bike - good for strength, comfort and handling
http://www.decathlon.co.uk/rockrider-63-2013-mountain-bike-black-id_8208677.html

Due to the weight and terrain I was leaning towards one of cellmans MAC kits, the uprated 12t looks good on a 26inch DH19 disc compatible rim, using the 9fet 30 amp 36 to 72 v inf 4110 controller, half twist throttle and ebrakes.
http://em3ev.com/store/index.php?route=product/product&path=36&product_id=138

11t top gear cassette
http://em3ev.com/store/index.php?route=product/product&path=41&product_id=63

5 x ZIPPY Flightmax 8000mAh 3S1P 30C - this will give me 55.5v and 8ah
http://www.hobbyking.co.uk/hobbyking/store/__32214__ZIPPY_Flightmax_8000mAh_3S1P_30C_UK_Warehouse_.html

I still need to think about charging solutions. From what I have read on here people using lipo tend to bulk charge without bms most of the time with HVC. Using balance charging maybe once a week to ensure the entire pack remains balanced.

I was thinking of using cycle analysis to set a LVC to ensure I do not over drain the batteries.

Any thoughts and suggestions would great!

 

[melodious]

Due to the weight and terrain I was leaning towards one of cellmans MAC kits, the uprated 12t looks good on a 26inch DH19 disc compatible rim, using the 9fet 30 amp 36 to 72 v inf 4110 controller, half twist throttle and ebrakes.
http://em3ev.com/store/index.php?route=product/product&path=36&product_id=138

Depending on your terrain and topography the 12T seems to be overkill unless your hauling ALOT of shite. 10T or 8T is the norm. If you don't mind a bit of personal information, please tell us where closer to where you live besides the country of the UK. It would help us to help you There are a lot of UK members here with a lot of years of experience riding above the 250W limit your general area.

I've read that European authorities are quite "wise" to modified E-bikes above the set European standard

 

[parajared]

The 6s 5ah batteries (http://www.hobbyking.co.uk/hobbyking/store/__9176__Turnigy_5000mAh_6S_20C_Lipo_Pack.html) offer more bang for the buck at $44.20 for 111 watt hours vs $45.89 for your 88.8 watt hour zippys.

Anyhow, it is going to be easier to keep the fiery little bastards balanced if you get higher cell count batteries. In the 6s example you would make either three 6s 10ah bricks for 66.6 volts or two bricks for 44.4 volts. You would solder the red wire to the red wire and the black wire to the black wire and put on a parallell harness like this one to connect the balance leads of two batteries together. Then you would have either two or three 6s 10ah batteries. Get a multicharger and now you can balance all three (or two) packs every time you charge.

Still not sure how this works. Fear not, here is a picture of how to do this (this pack is 6s 20ah): trust me this is way better, way cheaper than the octo-wire hell you see most people doing.

 

[footloose]

2 cents worth of opinion from another relative noob...

Re the bike. For reasonable speeds over reasonable terrain, I'm not convinced full suspension on a bike is worth it. And the rear suspension really minimizes available space in triangle -- ideal space for mounting batteries. Maybe go for a bike with just front suspension? Or even no suspension? Then go with some nice wide tires for a nice ride.

Re the motor etc. I have a Mac 10T / 9FET 3077 controller / 50V 12Ah NCM battery. Love the setup. Has torque in spades, with top speed ~30 mph. I live in very hilly area and weigh ~80 kilos. Programmed it for 30A max, ~1500W. Not sure you need the 4110 controller -- advice I've heard is that 3077 is a bit more efficient.

About the rim... how about going with one of the wider Alex rims instead of the DH19? I have the DM24, like it, it mounts a wide tire pretty nicely. Was looking at the DX32 last night (another thread). It looks even better for mounting a wide tire.

Lastly, and opinions vary on this, but... LiPo batteries just aren't worth their inherent risk to me. I've been happy with the NCM battery from EM3ev. Pretty small, pretty light, pretty good energy density, and pretty good chance of not burning my house down :wink:

 

[PaulQwerty]

Due to the weight and terrain I was leaning towards one of cellmans MAC kits, the uprated 12t looks good on a 26inch DH19 disc compatible rim, using the 9fet 30 amp 36 to 72 v inf 4110 controller, half twist throttle and ebrakes.
http://em3ev.com/store/index.php?route=product/product&path=36&product_id=138

Depending on your terrain and topography the 12T seems to be overkill unless your hauling ALOT of shite. 10T or 8T is the norm. If you don't mind a bit of personal information, please tell us where closer to where you live besides the country of the UK. It would help us to help you There are a lot of UK members here with a lot of years of experience riding above the 250W limit your general area.

I've read that European authorities are quite "wise" to modified E-bikes above the set European standard

Thanks for the reply
With regards to the 12t - this is exactly why I posted here - I would like to be able to tow around 100kg up a 1mile (1.6km) hill which averages around 6% but has peaks of 15%+. I realise that 10t and 8t are more popular and offer more top speed but how much weight can I haul with these up steep hills at lowish speeds without fear of over heating the motor, as you can probably tell, top end speed isn't that important to me, at my time of life I am looking for a hobby that promotes my health but with a practical benefit as well. I envisage cruising at around 20mph (30kph) with a very low cadence - hence the 11t (teeth) final gear cassette - btw do I need to get spacer to make this work? I am assuming the rear cogs on the donor bike will not fit the mac? Also I note on cellmans site that's 6 gear cassette fits fine between the standard drop outs but isn't available with 11 teeth final but the 7 speed with the 11 teeth final requires prising the drop outs slightly further apart, I am wondering how easy it is to do this with Aluminium frame bike?
Its can get confusing talking about 10t (turns) motors and 11t (teeth) gears - much confusion for me when I first started my research

I did mention in my OP that at the moment I reside in East Devon, UK. That should suffice for local members to contact me.

I believe, rightly or wrongly that UK authorities ie the police could enforce many laws in this country but choose to put the doctrine of "keeping the peace" at the top of their agenda and rightly so in my opinion. I am not saying the average police officer couldn't correctly identify a marginally illegal ebike, I just think that if it was being used reasonably they wouldn't care, after all, we are talking about a motor, battery and controller combination in step with the N American market so its not as though I am proposing an outrageous 60mph monster!

 

[PaulQwerty]

The 6s 5ah batteries (http://www.hobbyking.co.uk/hobbyking/store/__9176__Turnigy_5000mAh_6S_20C_Lipo_Pack.html) offer more bang for the buck at $44.20 for 111 watt hours vs $45.89 for your 88.8 watt hour zippys.

Anyhow, it is going to be easier to keep the fiery little bastards balanced if you get higher cell count batteries. In the 6s example you would make either three 6s 10ah bricks for 66.6 volts or two bricks for 44.4 volts. You would solder the red wire to the red wire and the black wire to the black wire and put on a parallell harness like this one to connect the balance leads of two batteries together. Then you would have either two or three 6s 10ah batteries. Get a multicharger and now you can balance all three (or two) packs every time you charge.

Still not sure how this works. Fear not, here is a picture of how to do this (this pack is 6s 20ah): trust me this is way better, way cheaper than the octo-wire hell you see most people doing.

Thanks for your advice. I see what your proposing - looks good for the money - would you be kind enough to recommend a charger that can balance charge both configurations?

 

[d8veh]

Regarding the gears: The MAC motor takes free-wheel gears that screw on a thread. Your bike will probably have cassette gears (free-hub) that go on a spline, so they won't fit.

Everybody has their favourite charger. Mine is the BC168 because it charges individual cells (up to 6 at a time) through the balance leads. They don't like accidental shorting though.

 

[Chalo]

Bike - I would like a full suspension mountain bike - good for strength, comfort and handling
http://www.decathlon.co.uk/rockrider-63-2013-mountain-bike-black-id_8208677.html

Strength, no; comfort, yes/maybe; handling, no. Expect a suspension bike to cost three times as much as a rigid bike of comparable quality, materials, and sophistication. Expect it to weigh at least 25% more than an equivalent rigid bike, but not to be as strong as an equivalent rigid bike. And understand that a single pivot rear suspension design such as the one you linked to will not fulfill the promise of a suspension bicycle (though it will work OK as a weak electric motorcycle pretending to be a bicycle).

11t top gear cassette
http://em3ev.com/store/index.php?route=product/product&path=41&product_id=63

DNP freewheels (the item you linked to is not a cassette) are widely acknowledged to be low quality, failure-prone units. Yes, you get the 11t sprocket. But no, you do not get a good freewheel. If you don't pedal, it doesn't matter.

From what I have read on here people using lipo tend to bulk charge without bms most of the time with HVC.

People using lipo without BMS tend to burn their battery down every so often, sometimes taking their bike and/or house with it. Be aware of what you are getting into.

A better bet for reliability and cost-effectiveness would be a rigid bike with a Shimano freewheel and a LiFePO4 or LiNiMnCo battery.

 

[PaulQwerty]

2 cents worth of opinion from another relative noob...

Re the bike. For reasonable speeds over reasonable terrain, I'm not convinced full suspension on a bike is worth it. And the rear suspension really minimizes available space in triangle -- ideal space for mounting batteries. Maybe go for a bike with just front suspension? Or even no suspension? Then go with some nice wide tires for a nice ride.

Re the motor etc. I have a Mac 10T / 9FET 3077 controller / 50V 12Ah NCM battery. Love the setup. Has torque in spades, with top speed ~30 mph. I live in very hilly area and weigh ~80 kilos. Programmed it for 30A max, ~1500W. Not sure you need the 4110 controller -- advice I've heard is that 3077 is a bit more efficient.

About the rim... how about going with one of the wider Alex rims instead of the DH19? I have the DM24, like it, it mounts a wide tire pretty nicely. Was looking at the DX32 last night (another thread). It looks even better for mounting a wide tire.

Lastly, and opinions vary on this, but... LiPo batteries just aren't worth their inherent risk to me. I've been happy with the NCM battery from EM3ev. Pretty small, pretty light, pretty good energy density, and pretty good chance of not burning my house down :wink:

Hi Footloose

"Full Suspension or not full suspension - that is the question" - many a night I have fallen asleep with that conundrum running through my thoughts! Bet I am not the only one!!

The hard tail option with enough space for one of cellmans triangle packs is very attractive plug and play option but pushing £500 landed with a charger compared to £250 for the lighter HK lipo and charger. 4kg vs 2kg plus I like the thought of suspension for comfort and safety when negotiating some of the poor road surfaces here.

I was leaning towards the 4110 controller because it can handle up to 72v which gives me more scope for matching combinations of lipo bricks without fear of exceeding the controller. I like the idea of being able to reconfigure/repair the battery pack in the future.

How many rear gears do you run - did you get an additional gear cassette from cellman - what final drive ratio do you use and how do you find your pedal cadence when cruising on the flat????

The rim width I chose was the one that I thought was a direct replacement from the donor bike - I thought this would avoid clearance and aesthetics issues - I don't want to change the front wheel tyre combo unless there are some good handling/safety reasons mainly due to cost

In terms of safety, I think all batteries can be dangerous, as can be the explosive liquids found in ICE. I am lucky in that II have out buildings with power and external power outlets. I intend to take every precaution whilst I familiarise myself with this new and exciting technology.

 

[Chalo]

For what it's worth, MAC motors impose a great deal of dish/offset, and you should consider using either an offset drilled rim that reduces spoke asymmetry, or a wide rim that contributes more lateral rigidity.

 

[PaulQwerty]

For what it's worth, MAC motors impose a great deal of dish/offset, and you should consider using either an offset drilled rim that reduces spoke asymmetry, or a wide rim that contributes more lateral rigidity.

Hi
I was hoping that by buying a motor already laced into a rim from cellman I wouldn't have to worry about "offset drilled rim" but if your saying that it is just a consequence of using a thinner rim with a MAC and it can be minimised with worthwhile effect and does not cause clearance issues on the proposed donor bike then I would be happy to order the MAC lased into a 26inch DM24. I would then just need to buy a suitable tyre. I am guessing it is the rim width and tyre combo that could cause clearance issues?

 

[dogman dan]

For what you want to do, I'd still go with EM3ev, but get his slowest version of the DD motor.

Why? Towing uphill will overheat any motor, even the 12t. The dd motors have better heat radiation, so they can take a bit more abuse. And, once abused, they typically need only new halls. The slow one will tow your load, and get to 20 mph on 48v, not towing. Not likely that you want to go any slower than that eh? It has no spoke dishing, so it will go fine over the bumps.

FS or no, Well for me, once you destroy your lumbar disks, it's FS or frock it. But that's my back, that built hundreds of houses in my youth. My gut feeling is that the speeds involved when towing a load mean you need only front suspension, if any. It is nice to have a moderately good shock on the front, better control in the bigger potholes, and some reduction in road vibration transferred to the hands. This makes a difference on a long ride, like 40 mile or more.

So Id say just look at good quality bikes with just front suspension that is fully adjustable, rebound and preload adjustable. That way you get some suspension for that "oh no" pothole you saw too late, but still have good frame space for the battery.

 

[PaulQwerty]

I also suffer from a bad back so would like FS. When I am not towing I would like to enjoy the bike for purely leisure activities. Cruising on the flat at 20mph is fine but I also enjoy the thrill of going down hills a bit more quickly so FS just for that odd occasion when I have to go over bad potholes and drain covers. I still have reasonable power in my old legs, just really struggle with my endurance on hills.

I was favouring geared over DD due to the weight savings and I had read many people favoured geared in hilly areas. However using lipo I can quite easily get 66v 30a 10ah, thanks to parajared that should do the trick in one of cellmans slower wound DD's. I like some of the benefits of DD - quiet, regen, fewer moving parts, not so keen on the lack of freewheel for human power only cycling though.

So many choices..

 

[d8veh]

This suspension seat-pin is as good as decent rear suspension for comfort. It's nothing like those cheapo ones. I have bikes with proper air suspension and the NCX is just as comfortable.
http://www.ebay.co.uk/itm/SUNTOUR-NCX-SP12-SUSPENSION-SEAT-POST-NEW-MODEL-UNBELIEVABLE-COMFORTABLE-/290886050905?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item43ba28e459

 

[footloose]

You have outbuildings?
You are living the good life!
Disregard my comments re LiPo.
If I had separate structure at home,
and no need to store or charge battery
at office during day, I'd go with LiPo.
LIving as I do in crowded California,
have to be a bit conservative.

 

[footloose]

Double post. iPhone. Oops.

 

[999zip999]

Get a D.D. motor with an old comoly frame bike used and cheap. Buy one with good derailer for 100.00 in the U.S. as they were 600.00 dollars bikes with japanesse bearing. A NMC for a small size battery or I like lifepo4 48v. Or lipo and store and charge in a barbaque.