I'd drop Frank an email (I have ) and have a Bafang and controller on its way for my Peugeot DIY bike. He gives very good impartial advise and stocks the Bafang and Puma motors.

 

Das Elektrorad von Frank Scheftlein: Komplette Pedelec- / Elektrofahrrad Umbausätze und Ersatzteile von Bafang, Puma (eZee), Tongxin u.a.

 

Thanks for that, I have a mountain bike that would be perfect.

Hi Flecc,

 

Just thought that the Giant Lafree creation could have been one of yours, I was wrong to laugh at it, oops apologies.

 

Not one of mine Polar, but even if it had been, I'd appreciate the humour anyway.

 

Actually I thought you summed that bike up perfectly, having experience of the limitations of Lafree brakes and handling myself.

.

Polar, please excuse me if I'm teaching Grandmother to suck eggs, but something that occurs to me is that when I had my Agattu I thought it was great but I didn't get on with the higher assistance level being at lower pedaling cadence. To get the best assistance for hill climbing I had to stay in a higher gear and reduce cadence, when my legs wanted to change down to a lower gear and increase cadence.

 

I sold the bike on and went with a Tongxin motor which I really like, as it suits my riding style better, but it isn't as good on steep hills as the Agattu.

 

Having read posts on here recently I could have got around that on the Agattu to some extent by changing the motor sprocket from 9 to 11 teeth which would have allowed a somewhat faster cadence in lower gear, whilst maintaining more of the motor assist, for hill climbing and might have resolved the problem.

 

It might be worth considering going back to standard gearing at the hub with increased motor sprocket and see if that works for you before changing bikes.

Prices

 

I'm really impressed with the range of the Cytronex bikes, I only get about 20 miles from my 10Ah bat, but that is on Hi most of the time. 45miles with two batteries is a good distance, shame the price has just gone up.

 

I am afraid we are all just about to see a price hike as the price of raw materials continue to soar.

 

All the best

 

David

I'm really impressed with the range of the Cytronex bikes, I only get about 20 miles from my 10Ah bat, but that is on Hi most of the time. 45miles with two batteries is a good distance, shame the price has just gone up. I'm with you on the snow, a real pain, rain and wind not a problem but snow and ice is a no go. Bring on spring.

 

Hadn't noticed the price had gone up - though it wouldn't surprise me now that I'm considering getting a new one.

 

Where did you hear about the price rise?

Polar, please excuse me if I'm teaching Grandmother to suck eggs, but something that occurs to me is that when I had my Agattu I thought it was great but I didn't get on with the higher assistance level being at lower pedaling cadence. To get the best assistance for hill climbing I had to stay in a higher gear and reduce cadence, when my legs wanted to change down to a lower gear and increase cadence.

 

I sold the bike on and went with a Tongxin motor which I really like, as it suits my riding style better, but it isn't as good on steep hills as the Agattu.

 

Having read posts on here recently I could have got around that on the Agattu to some extent by changing the motor sprocket from 9 to 11 teeth which would have allowed a somewhat faster cadence in lower gear, whilst maintaining more of the motor assist, for hill climbing and might have resolved the problem.

 

It might be worth considering going back to standard gearing at the hub with increased motor sprocket and see if that works for you before changing bikes.

 

I'm a beginner at this so no problem, I'd really like to try a different front sprocket, it is smaller at the front for higher cadence ? Any idea where to get one from, 50cycles show none in stock. I agree with some of the reviews about the way it makes you use a lower cadence, spinning faster is definitely easier on the knees and more natural to more experienced cyclists.

 

I am afraid we are all just about to see a price hike as the price of raw materials continue to soar.

 

All the best

 

David

 

Something that has really surprised me as I read through the A to B mag, and on this forum is the way prices have gone through the roof. Some places batteries have gone mad, I have to say spending £400 and up on a battery will put a lot of people off. I think it will kill the electric car market before it has begun to thrive. New tech is definitely required.

 

Hadn't noticed the price had gone up - though it wouldn't surprise me now that I'm considering getting a new one.

 

Where did you hear about the price rise?

Link below from the Cytronex main site. Add a bike to the basket and you get to the next page with Components. I hope it works.

Cytronex Components --- Cytronex - The UK's leading electric bike

 

I'd really like to try a different front sprocket, it is smaller at the front for higher cadence ? Any idea where to get one from, 50cycles show none in stock. I agree with some of the reviews about the way it makes you use a lower cadence, spinning faster is definitely easier on the knees and more natural to more experienced cyclists.

 

No, you need a larger motor sprocket. Your standard one is a 9 tooth, the only larger option is an 11 tooth which 50cycles normally stock but were out of recently. They should be getting more in I assume.

 

For information on fitting these, see this webpage on my site.

.

Edited February 12, 201016 yr by flecc

It would be smaller chainwheel to give lower gear and cadence, but I'm meaning the panasonic motor drive sprocket. On Fleccs' panasonic repairs info page there's a very good description of how to change the motor drive sprocket and the effects it has. It's here;

repairsnew

 

Not sure where to get one if 50C don't have one though.

No, you need a larger motor sprocket. Your standard one is a 9 tooth, the only larger option is an 11 tooth which 50cycles normally stock but were out of recently. They should be getting more in I assume.

 

For information on fitting these, see this webpage on my site.

.

 

After a bit of thought got there in the end.

 

It would be smaller chainwheel to give lower gear and cadence, but I'm meaning the panasonic motor drive sprocket. On Fleccs' panasonic repairs info page there's a very good description of how to change the motor drive sprocket and the effects it has. It's here;

repairsnew

 

Not sure where to get one if 50C don't have one though.

 

Lots of good reading. Thanks again. I have to say I do really like my pro connect, its well built coping with the poor roads cold rain etc, with the ability for some fine tuning via gearing to suit individual preferences. Is there another with 2 yr guarantee? I would like to have a go on some more local products especially when I'm fitter.

Price Rises

 

I am intrigued that there is talk of prices rising. I agree it will kill the market dead if that happens. We are supplying new 36V/16Ah high current dump batteries at around £300. Is that competitive? - I wonder if the industry is playing at the 'hp' game and trying to make after market money. Not a great idea I feel? Our top of the range tourer with that bettery checks out at £1399 with really quality forks etc, and the battery is lab rated 37V 14.4Ah or nearly 650Wh.

 

I think prices have to be kept low..... we want volume not niche sales, surely?

I am intrigued that there is talk of prices rising. I agree it will kill the market dead if that happens. We are supplying new 36V/16Ah high current dump batteries at around £300. Is that competitive? - I wonder if the industry is playing at the 'hp' game and trying to make after market money. Not a great idea I feel? Our top of the range tourer with that bettery checks out at £1399 with really quality forks etc, and the battery is lab rated 37V 14.4Ah or nearly 650Wh.

 

I think prices have to be kept low..... we want volume not niche sales, surely?

 

Any pics or links ? Sounds interesting ........

I am intrigued that there is talk of prices rising. I agree it will kill the market dead if that happens. We are supplying new 36V/16Ah high current dump batteries at around £300. Is that competitive? - I wonder if the industry is playing at the 'hp' game and trying to make after market money. Not a great idea I feel? Our top of the range tourer with that bettery checks out at £1399 with really quality forks etc, and the battery is lab rated 37V 14.4Ah or nearly 650Wh.

 

I think prices have to be kept low..... we want volume not niche sales, surely?

 

Yes, especially when you consider that Lipo battery chemistry can be purchased for well under $20 / Ah...£400 for an E-bike battery is really...well...taking the 'mick'.

no links yet. Some pics but I am having trouble uploading. Will try tomorrow.

Yes, especially when you consider that Lipo battery chemistry can be purchased for well under $20 / Ah...£400 for an E-bike battery is really...well...taking the 'mick'.

 

But to be fair as a UK based supplier they do have to pay VAT, shipping, import duty and still make some profit. I think you've got a bit mixed up with the price there, don't you mean 2USD/Ah From someone that does actually buy batteries in quantity, I can assure you good stuff doesn't come so cheap in China and things like finished cases with BMS and charger is not a fair comparison to a LiPo pack with just a balance lead coming out that comes with little or no guarantee, has claimed life cycles of about 200 and WILL burst into flames if over charged. Li Po is good but it's not for everyone and would you give your mother a LiPo equipped bike?

 

How about the A123 15 and 20Ah cells that are now available. Now they are the business and priced at 2.5USD/Ah, so 50USD per 20Ah and 37.50USD per 15Ah. Most of the performance of lipo with lifecycle better than the best previously available LiFePO4:

 

Model: AHP 70165227

Capacity: 20Ah

Size: 7.0X 166X227mm

Weight: 480g

 

Model: AHP 68150211

Capacity: 15Ah

Size: 6.8X 150X211mm

Weight: 400g

 

Try 400A constant out of 20Ah cell

Pricing is a bit of a mine field. We believe a target UK retail price of sub £20 per Ah, or sub 60p per Wh is fair....

Pricing is a bit of a mine field. We believe a target UK retail price of sub £20 per Ah, or sub 60p per Wh is fair....

 

 

Yes that is fair probably more than fair TBH, so good on you.

 

EF, yes, agreed VAT and duty will raise the price but this will be offset to some extent by bulk purchase. I was comparing the retail price from Hobbycity of some 5Ah packs I've just bought so yes, they come in at $2 / Ah per cell so a 37v 10ah pack works out to be $200 plus shipping and VAT or approx £180 delivered retail. Trade will of course be less than this and the BMS and case can't cost that much trade so a retail price of <£300 is IMHO about right and about what the market can just about bare... The high cost of replacement batteries is what will kill any long term interest in E-Bikes if customers are faced with the prospect of a new battery that costs 50~70% of a new bike every few years.

 

I agree about the dangers of Lipo but as you know on ES and in my own experience with careful voltage and charge management the early horror stories of a few years ago have largely disappeared and life cycles are well past 200.

 

I know you have these new Prismatic cells for sale and I'm certainly interested to see how they work out, maybe on my next battery refresh I'll drop you a PM.

For sure a small BMS that can do 20A contant output isn't so expensive but when you start looking at something that can handle 60 or 80A constant they don't come in cheap. Likewise with the case. If you go with 1 of the standard types you see around they're not expensive but it does all add up by the time you've added all the small parts, shipping, VAT, Duty and some profit.

 

It is pretty hard to compete with the likes of Hobbycity which have a massive turnover and really do keep their prices low from what I've seen. The li po does look really good but I can't see it ever being mainstream with the safety concerns there are not to mention the hassles with breaking down packs to charge etc. For the interested enthusiast sure but for the average commuter, I don't think so. I think it's great that there is the choice.

 

A 36V 15Ah (generally tested to more like 16Ah, nominal 39.6V) set of the 15Ah A123 cells made into a pack with a reasonable BMS is gonna be roughly somewhere in the region of 350-400GBP including air freight to UK. Not the cheapest option but these aren't 2C cells

I hear you about the safety concerns but I believe Wisper is about to go mainstream with this chemistry so I think its coming of age....also the Cells from HobbyCity aren't 2C either However, that's not relevant with UK legal E-Bikes as we don't need to pull more than 2/3C...

I hear you about the safety concerns but I believe Wisper is about to go mainstream with this chemistry so I think its coming of age....

 

If the li-po being referred to here is lithium polymer, I don't understand the discussion. Wisper are just one of the many e-bike companies who have been using it for two and more years in complete safety, while Panasonic have been using it for five years on e-bikes.

 

Actually polymer is more a construction than a chemistry.

.

Edited February 15, 201016 yr by flecc

Thanks Flecc, I was getting confused as well

Ah, thanks for the correction Flecc, I thought they, like other suppliers, where using Lithium Ion rigid case batteries not the 'soft cased' Lithium Polymer...

Ah, thanks for the correction Flecc, I thought they, like other suppliers, where using Lithium Ion rigid case batteries not the 'soft cased' Lithium Polymer...

 

Polymer is very much mainstream now, used by Panasonic in nearly 20 makes, plus Gazelle, Yamaha, Giant, eZee, Wisper, Powacycle, Powabyke and many more.

 

NiMh is now a rarity, LiFePO4 is barely starting to appear in production bikes, and the SCiB type (which isn't really suited to e-bikes) is only on one make.

.

The lithium polymer that is used in RC applications that NRG and myself are referring to is not the same as what is used in these e bike batteries.

 

I think the main reason lifepo4 hasn't been accepted by the bike manufacturers is that lithium polymer is cheaper per w/hr, generally has higher energy density and lasts long enough for the warranty

 

The lithium polymer that is used in RC applications that NRG and myself are referring to is not the same as what is used in these e bike batteries.

 

Do you mean the RC based ones use the lithium iron phosphate chemistry in a polymer construction?

 

 

I think the main reason lifepo4 hasn't been accepted by the bike manufacturers is that lithium polymer is cheaper per w/hr, generally has higher energy density and lasts long enough for the warranty

 

I rather doubt this. Some leading companies have been testing LiFePO4 in conjunction with their battery manufacturers for a long time now, but they haven't been able to achieve the necessary reliability in mass production circumstances in compact forms. LiFePO4 is possible of course, but with adequate reliability and high enough discharge rates they are bulky, necessitating either smaller capacity or even larger battery installations, both a backward step.

 

eZee have been experimenting with LiFePO4 since late 2006 and are just at the point of limited introduction with smaller capacity, while Wisper and their battery supplier AE agreed not long ago that the technology was not quite ready yet.

.

Well I think it will not be long before LiFePO4 has been accepted by even the most demading buyers. It already has been as it will be fitted into production cars soon. LiFePO4 doesn't have to be bulky and can sustain high discharge rates.

 

I have stacks of these prismatic cells sat here:

A123Systems :: Products

 

They will do approximately 15-20C constant with even higher peaks and weigh only 467g for a 3.3V nominal 20Ah cell. Size 7mm *165mm * 227mm. Also come in 15Ah version with 400g, 6.8mm * 150mm * 210mm. Claimed cycle life of something like 7000 cycles and 10-15 years in automotive application.