Possibly the easiest question in the world..ever

[Pete]

Well, not quite. But you might not have read this if it was another thread saying help wanted for newcomer!
For the past couple of weeks I have been lurking round this forum trying to glean information that would be useful in helping me choose an assisted bike. I thought it would be easy, how little I knew! The more I read the more I realised I needed to read and however much I learned, there was still more to learn. The expertise of some on this forum is outstanding, people like flecc and others. However, there is a limit to how much you can absorb and make sense of for ordinary mortals like me.
I realise that although I have learned quite a lot by just following threads and reading FAQ's there are a few fundamental things I don't understand. Like these two:

1. MOTORS From a practical standpoint is there an obvious clear choice between the Panasonic crank drive setup and the hub type motors, which to me seem to have significantly less to go wrong. Or, is it horses for courses and if so, which motor for which course?
I read through one of fleccs longer pieces, he writes in a nice clear style and I felt quite confident that he was demoting the crank drive into second place then right at the end seemed to be saying the opposite. Now this is my fault for not fully comprehending, or perhaps it has been overtaken by newer technology. Whichever, it does underline the difficulty someone with little knowledge has in making sense out of sometimes opposite points of view. So, for example if I come on here and announce my new hub drive bike will I get a flurry of responses saying, why did you buy that, you should have gone for a Panasonic drive. Or not.

2 BATTERIES. This is similar to my first question, in other words I am asking a simple question that probably only has a complicated answer! Is there a clear winner in the battery type stakes? Again I thought I was getting there only to be cruelly confused at the last. The question - one type, the li-ion type I think, seemed to deliver a good range but it was very detrimental to the battery to let it run right down between charges, and I think it was suggested that they should not be discharged below 1/3rd. So when a range is quoted for this type does the figure take this into account or is it only a theoretical figure based on full discharge which you are not supposed to do?

Thanks for reading

Pete

 

[OneWayTraffic]

I will just briefly answer your questions by summing up what you've read. Crank drive systems have lower maximum efficiency than hub systems. However for certain applications the advantage of gearing outweighs the extra complexity. Those applications would include really steep hills and possibly towing as well. They will climb any hill, while a regular geared hub or especially direct drive (not common in the UK except on imported kits) will stall out. However if you already have a bike, and climb hills with it, don't worry too much with this; any hills you can climb now will be far easier with a motor, any motor helping.

Lithium batteries are really the best available as of right now. LiMn is the common type which you will encounter in 90% of bikes out there right now and is very reliable and offers good safety and power/energy density. You can use all the charge i.e. ride it until the BMS cuts out the motor but for maximising the life of the battery it's better to keep them between 30-100 charged. For winter storage you want them at 60% state of charge. A voltmeter could help here. They should never be discharged to zero volts, which will certainly destroy them.

The good news for you is that if you buy an off the shelf bike, one of the main brands, then you won't really need to worry about this too much. Just charge it the night before, take it out and ride it and then plug it in at night. The inbuilt electronics do a fair job of safeguarding the battery for you. You can expect 2 years out of a battery, though some have been known to last for 3 or more and some (usually pre 2008) would die much faster. The technology is developing very rapidly.


Same for the distinction between hub and crank drive. If you go for one of the better brands, then it won't really matter all that much for 90% of people out there. If the bike fits you and you treat it well, you can't really go far wrong. Couldn't say that 4 years ago!!

 

[z0mb13e]

Hi Pete,

I would suggest trying to get a test ride on one of each type. Once you understand the options, the difference seems (to me at least) to be one of preference.

Hub motors often come with throttle control (as well as pedelec) while (most) crank drive bikes are peddle assist only and vary their power input based on the amount of effort the rider is putting in (torque sensor).

I've never ridden a Panasonic type bike, it just didn't appeal.

As for batteries their are better informed people on here to debate that, but I can tell you that li-ion type batteries will have a battery managment system built in that will stop the batteries from being damaged - they will switch off the battery before they are empty. I would expect the quoted range to take this into account.

 

[Haku]

You can expect 2 years out of a battery, though some have been known to last for 3 or more and some (usually pre 2008) would die much faster.

I can vouch for that, I use my UM36 daily and the Panasonic li-ion battery I used with it is almost 2 years old now, it'll still get me about but the range is nothing like when it was new, I'd always carry the charger when going to friends/work.
With winter almost here I needed a replacement because the cold really hampers the range, I was lucky enough to get one off eBay for £100 off normal price, it's a year old but has had almost no use and been topped up every 6-8 weeks, last night I did a journey with it that would have flattened my old battery to the point where I crawl on the last hill home, I could have easily done that journey 3-4 times over on the replacement, so I'm very pleased

I expect someone who doesn't use it nearly as much as me would've gotten more than 2 years of good range out of the same battery, I do tend to ride it hard as the old battery has had well over 1000 charges now.

 

[tillson]

As others have said, you really should try both systems. I have very little experience of hub motored bikes as mine is the Panasonic system.

All I can say about it is that the motor system has been faultless and I have been using it daily for the past 18 months in all types of weather. For me, I find the Panasonic system very natural and intuitive. It seems to integrate seamlessly with the leg muscles. Using the three levels of power available, I find that I can build on my fitness by using the lower power setting or if I am feeling lazy after a busy day at work, come home on the higher setting with minimal effort.

Speaking personally, there is nothing that I would change about the Panasonic system. Because it adds to your pedal effort by determining how hard you are pedalling and then driving directly onto the chain, it makes the system a sort of leg muscle amplifier. This combined with the various power settings makes it very versatile.

However, this may not be everyone's cup of tea, but you should certainly try a Panasonic system before making your final decision.

 

[Pedalo]

Mainly from reading this forum I got this impression:

-Would you like to put some effort in? (i.e. pedal a bit!)
-If no
- {{ buy a high powered hub motor with throttle control e.g. Wisper, Ezee}}
-Else
-{{
- Do you like to pedal with high cadence?
- If yes
- {{ Consider a Cytronex }}
- Else
- {{ A Crank drive motor might be best for you. e.g. Kalkhoff, E-motion}}
- }}

Probably a bit simplistic. Steepness of hills, range etc also has a bearing but do try before you buy if you can.

 

[flecc]

The seeming contradiction in my article concerned the ability of both types on the steepest hills. The drive through the gears types have very little limitation in this respect while hub motors are left wanting on the steepest, leaving the rider to make up the shortfall if they are able to.

If you are a powerful rider in a very steep hill area you might well be ok with a powerful hub motor, but if you are not a strong rider and have to tackle the very steep hills, 1 in 7 upwards for example, the drive through the chain is the choice.

In most areas of Britain with hills rarely exceeding 1 in 10, either type is fine for any rider.

But as said by others, there's a big personal preference element in this as well, so always try both types before buying since they are very different in their nature.
.

 

[Fecn]

- Do you like to pedal with high cadence?
- If yes
- {{ Consider a Cytronex }}
- Else
- {{ A Crank drive motor might be best for you. e.g. Kalkhoff, E-motion}}
- }}

There is also the option to use an 11-tooth motor cog on the Panasonic system to raise the cadence. The cog costs £15. However, doing so will result in a bike which assists to well above the legal limit (unless you change the hub gearing to compensate).

 

[Phil [OnBike]]

Test Rides

Hi Pete,

It really is a good idea to try out the various technologies available to you from the popular manufacturers - There is no one bike to suit everyone.

I'm not sure where you are based, but you're welcome to come to OnBike in either Kidderminster or Presteigne where you can try out a range of Panasonic crank drive bikes from E-motion and Monark, plus a range of hub drive bikes from eZee, Wisper, Powabyke etc...
We have about 20 demonstration models at the moment that you can try out one after the other - a great help if you are not too far away!

If this is of any interest to you, just let me know.

Cheers

 

[Sir_Bob]

oudie

the answer is easy just get one that fits your needs. i am very big so need an xxl. If you have a gammy knee like me make sure you can make your leggy straigt.

thx

bob

 

[Pete]

Thanks for all the advice

I'm afraid I have been away since starting this thread so just read the responses. Not only are there several replies, some of them within hours, but the amount of material in them is great. I have noticed looking through this forum over the past few weeks how willing everyone is to give their time and experience and I have to commend you all.

The common sensible thread running through all the replies is to try out as many types as you can and I am making arrangements to do that. In advance of that though I have a few queries arising out of your replies:

If you are a powerful rider in a very steep hill area you might well be ok with a powerful hub motor, but if you are not a strong rider and have to tackle the very steep hills, 1 in 7 upwards for example, the drive through the chain is the choice

I wish, but no I'm not a strong rider. If I opted for a hub motor is there any preference between front and rear hubs. I was thinking for example that with a front hub, which has less of the weight on it, you could perhaps spin the wheel on slippery surfaces and come a cropper? On the other hand it would give you two driven wheels - a biking 4X4, so it would be better on poor surfaces?

There is also the option to use an 11-tooth motor cog on the Panasonic system to raise the cadence. The cog costs £15. However, doing so will result in a bike which assists to well above the legal limit (unless you change the hub gearing to compensate).

I am getting on a bit and have never been a cyclist so my cadence tends to be high as I choose easier ratios to pedal. I assume that this would change on assisted bike. Is there a cadence that is generally accepted as being optimum, or is it just a matter of personal preference?

while (most) crank drive bikes are peddle assist only and vary their power input based on the amount of effort the rider is putting in (torque sensor).

Do they also provide power depending on how fast you are pedalling or is it just the resultant pressure on the pedal?
Do Hub motor setups with pedelec respond to pedal pressure (and rate) in the same way?

a battery managment system built in that will stop the batteries from being damaged - they will switch off the battery before they are empty. I would expect the quoted range to take this into account.

If the battery management system does this why are there quite a few warnings on the forum about not running batteries into the ground or they won't recover/have a shorter life. How could this happen? In storage?

Lithium batteries are really the best available as of right now. LiMn is the common type which you will encounter in 90% of bikes out there right now and is very reliable and offers good safety and power/energy density. You can use all the charge i.e. ride it until the BMS cuts out the motor but for maximising the life of the battery it's better to keep them between 30-100 charged.

Can the BMS be tweaked so that it cuts out at this 30% level or am I not understanding, does it do this anyway?

It seems like all batteries have a maximum number of times they may be charged, say 300

Do they retain good efficiency up to this point or is it a gradual taper. I think I read somewhere on the forum that one type, LiFePh? had showed no deterioration over many months (9?)

Is the maximum number quoted for full charges from this say 30% level, or do partial charges count towards this.

Following on from that is there a particular battery type that takes kindly to charging from a part charged state? In other words if you regularly ride to half the batteries capacity is it better to charge after each ride or after 2 rides?> Which will give the longer life?

One reason I am asking this is that I am not a commuter, I am retired, so my riding will not be to such an intense pattern as every day. I will likely often put the bike on the car and drive somewhere to ride. I already have a small inverter in the car which I use for computer, coolbox, chargers for phones etc and I was thinking that I could use this as I drove between rides to top up, but not if it would significantly reduce the batteries life. Is this idea feasable anyway, what do these chargers draw - the inverter is rated at 350 Watt continuous and 500 Watt peak?

Well I think that is enough to be going on with!

Many thanks

Pete