905se

[Jed]

any chance of some details on the changes you are making? will you be adding a off-road/turbo mode ala the Ezee bikes?

thanks
Jed

 

[Wisper Bikes]

any chance of some details on the changes you are making? will you be adding a off-road/turbo mode ala the Ezee bikes?

thanks
Jed

Hi Jed

The 905Se is based on the 905e, the frame and look will be exactly the same.

The concept behind the 905 series was to create an electric bike that one can happily cycle without power. With power on we wanted the cycle to morph into the most light weight and easily handled electric bike on the market. The 905e came close to this, however in the interest of keeping prices under £850.00 we used some components that were good but not perfect.

On the 905Se we have upgraded many of the parts to make the "power off" cycle even better to ride. We have also made use of the latest and most powerful lithium manganese battery that was not available a year ago.

The upgrades include;

7 Shimano Alivio gears. We have introduced a 11 cog high gear. Alivio chain, dérailleur and gear change system.

New 52 tooth chain wheel, five point hollow cranks and alloy pedals from Power Wheel.

New hi tensile stainless steel spokes.

New puncture resistant tyres and upgraded valves.

New metallic black paint work.

All nuts and bolts are now either stainless or alloy.

New upgraded main bearing and cassette style front wheel bearing.

Solar powered front light. Our EU bikes have a dynamo on the front wheel and superb permanent front and back lights, we are considering making these standard in the UK too.

Upgraded back light.

New Zoom adjustable front suspension.

Upgraded saddle suspension.

Choice of saddle styles.

New polycarbonate mudguards.

New 13.8 amp battery.

4 point switch, 1. power off, 2. Pedelec mode, 3. Ebike mode (with throttle), 4. Off road mode (de-restricted).

These are only 21 of the 42 improvements and changes made. As soon as the bike is on the market we will publish the complete list of improvements and changes.

The price for the 905Se will be £1000.00. As the bike has been such a hit in Europe we will only have limited numbers on the first container, but we are taking advanced orders with a 33% deposit.

Best regards David

 

[JohnInStockie]

That sounds like a very impressive specification David. Im looking forward to hearing what people think

John

 

[Wisper Bikes]

Thanks John!

We hope we have correctly interpreted the needs of Pedelecers, but only time will tell!

Best regards David

 

[Steelman]

905e

Hi David

Wow...Just read message bout the 905se...All I can say is...I want one!!!
As a current owner of the 905e...The upgrades sound as if they will make the already superb 905e even better!!!
I have done 500miles now since april and am still thouroughly enjoying every minute I spend on the bike.
Will the upgrades include a sealed bottom bracket assembly?
I had a replacement axle off yourselves recently as the original failed....and although the bike is back to performing as it should I still think the sealed units I have experienced on my normal bikes are smoother and more robust than the axle/bearing assembly fitted to the 905e.
Better start saving!!!

Cheers

Rob

 

[Wisper Bikes]

Hi Rob

Thanks for your kind comments!

The new main bearing will fit the 905e, if you have any more problems I will replace it with a new one.

Best regards David

 

[frank9755]

David,

The 905SE sounds very tempting.

I also read your post the other day about bringing out a low-cost lead acid battery alternative with interest. To extend choice further, do you have any plans to offer an NiMH option?

I'm looking to buy two bikes (for my wife and myself). However, largely based on what I've read on these boards, I'm concerned about the suitability of Lithium batteries - while not wanting the extra weight of lead. Is NiMH a likely future option?

Frank

 

[Wisper Bikes]

NiMH Batteries

Hi Frank

The likelihood of us going down the NiMH rout is very limited at the moment.

We are pleased with the new Lithium Ion technology and it seems to be moving forward all the time. The latest Lithium Ion batteries have cathodes which are 33% Cobalt, 33% Manganese and 33% Nickel seem to be very stable.

Our latest battery which is made up as above packs a huge 13.8 amps is very light and stable, I am the first to admit that I am no expert but the manufacturer we are working with supply people such as Panasonic with batteries and I do trust their opinion..... which is very definitely stick with Lithium Ion - not even Lithium Polymer!

If you have any worries that you would like me to find the answer for please ask.

Best regards David

 

[MaryinScotland]

Might you do an equivalent improved 705? My personal preference is for a step-through, upright-position bike. The 705e is my kind of style, but right at the top of my "acceptable" weight range. If you could shave a bit of weight off, and give it that 4-mode switch, I'd be seriously interested.

Mary

 

[frank9755]

David,

Thanks for getting back to me.

My concerns on Lithium batteries come from reading on this forum and in A to B magazine. They are:

1. Cut out on hills. Because the voltage of a lithium battery drops under loading, it can sometimes trigger a cutout. As peak loading occurs when you are going up a steep hill, it is pretty inconvenient. This seems to be more of a problem on higher powered bikes. People have reported it on Ezee bikes (and I think also on the Sparta Ion), but there have been no reports of this happening with Powacycles, where the much lower powered motor does not make such demands on the battery.

2. Rapid loss of capacity and hence range with normal usage. People talk about losing anything from 10%-100% of capacity per year of life. The problems seem to arise if you use the battery to anything near its capacity (ie run it down past half charge). However, that is what I would want to do as I have a 25-mile return trip to work. NiMH by contrast seems to be much more robust. People on this forum report no loss of range after 2 years with deep discharges being possible.

Therefore my questions are how can I be sure that a lithium battery would give satisfactory operating performance - ie ability to climb long hilss without cutting out and ability to get me to work and back without having a very short life?

Thanks

Frank

 

[Wisper Bikes]

705Se

Might you do an equivalent improved 705? My personal preference is for a step-through, upright-position bike. The 705e is my kind of style, but right at the top of my "acceptable" weight range. If you could shave a bit of weight off, and give it that 4-mode switch, I'd be seriously interested.

Mary

Hi Mary, yes there will be a 705Se available in 2008, but until then we only have the standard 705e.

Best regards David

 

[uk_steve]

Refrence Whisper 905se

i will try and get to the new forest but if i cant? i tel you at somepoint for more info

Kind Regards Steve

 

[Wisper Bikes]

Hi Steve

I hope you can get there, the 905Se prototype arrived today and all though there are a couple of small improvements to be made we have a very nice ebike!

Give me a call any time 01732 789681.

Best regards David

 

[MaryinScotland]

Hi Mary, yes there will be a 705Se available in 2008, but until then we only have the standard 705e.

Best regards David

Hi David, thanks for that. I'll live with my Urban Mover for a while, but keep an eye on your website for next year.

Re my question on the other thread: I won't now be able to get to the New Forest event, but thanks for the offer of Brompton parking space. Another time, maybe...

Mary

 

[Wisper Bikes]

New Forest

Hi Mary

Sorry to hear you won't be at the New Forest rally, I hope to meet you soon.

Best regards David

 

[Wisper Bikes]

Lithium Ion explained

My concerns on Lithium batteries come from reading on this forum and in A to B magazine. They are:

Hi Frank as promised I have some answers for you from our battery guys.

1. Cut out on hills. Because the voltage of a lithium battery drops under loading, it can sometimes trigger a cutout. As peak loading occurs when you are going up a steep hill, it is pretty inconvenient. This seems to be more of a problem on higher powered bikes. People have reported it on Ezee bikes (and I think also on the Sparta Ion), but there have been no reports of this happening with Powacycles, where the much lower powered motor does not make such demands on the battery.

I think this probably comes as a result of companies not specifying the correct type of lithium ion battery. All battery technologies such as Nickel Cadmium, Nickel Metal Hydride, Lead Acid and Lithium ion have product variants designed for high temperature, long cycle life, high rate discharge etc etc. Many Lithium Ion cell suppliers in China do not have their technology optimised for applications such as E-Bikes and therefore although their product may appear attractive on paper with good capacity, light weight etc etc the performance under high rate discharge is not so good and therefore they can have a high voltage drop under high load conditions. A correctly designed lithium battery should however be at least as good and perhaps even better at high rate discharge than all other battery types. The hybrid cathode material we use in our E-Bike batteries allows peak discharge at up to 5 times to rated capacity of the battery with very little voltage drop. Based on our 36V 10 Ah this means the cells can easily deliver 1800 Watts of power if needed. The limitation is therefore usually caused by the battery protection module as follows :

1. If the cell is not well suited to high rate discharge then the voltage can drop under load. It may therefore momentarily drop below the minimum voltage level of the protection module and the battery will as a result shut down thinking that the battery has reached the end of its discharge.

2. If the current limit of the battery is set too low or the motor wattage too high then under high rate discharge conditions the current demand from the motor can exceed the maximum current setting and again the battery will shut down to protect that battery and load.

Our battery has a max current limit on the battery protection module of 20A so in principle the battery can deliver 36V x 20A = 720 Watts.

2. Rapid loss of capacity and hence range with normal usage. People talk about losing anything from 10%-100% of capacity per year of life. The problems seem to arise if you use the battery to anything near its capacity (ie run it down past half charge). However, that is what I would want to do as I have a 25-mile return trip to work. NiMH by contrast seems to be much more robust. People on this forum report no loss of range after 2 years with deep discharges being possible.

It is hard to make a comparison without testing products under controlled conditions but it is widely acknowledged by cell manufacturers that lithium ion cells display better cycle performance and lower capacity losses under almost any condition. Again this assumes that the cell type used is suited to continuous charge and discharge characteristics of the E-Bike. As detailed before all batteries will lose capacity as a result of being charged and discharged this cannot be avoided but based on our standard specification then you should expect around 500 charge and discharge cycles and still have 70% of the original capacity. Given a daily commute of 5 days a week this should work out to around 2 years use before a significant loss of capacity is noticed. I can only assume that if many lithium ion users are reporting rapid capacity loss then the quality of the cells they are using must be very poor.

Therefore my questions are how can I be sure that a lithium battery would give satisfactory operating performance - ie ability to climb long hills without cutting out and ability to get me to work and back without having a very short life?

You can only make a judgment based upon the specification supplied by the manufacturer and your belief in their figures.

I do hope this helps

I am going to start a new thread with this answer as I am certain it will attract interest.

Best regards David

 

[frank9755]

Hi David,

Just wondering how the 905SE is coming along? Will there be a launch soon? Looking forward to it!

Regards,

Frank

 

[frank9755]

No news?

Or updates on timing?

 

[Basingstoke]

Wisper 905se Test ride

Hello everyone!
The Wisper 905se. I will be test riding this bike at the weekend. I have never
tried any electric bike before but i will give you 100% honest review by sunday. Hopefully the bike will be great because i want to buy one. Time will tell.

Regards

Paul

 

[flecc]

Thanks Paul, I'll look forward to reading that. Let us know what it's like on hills as well as speed on the flat if you get a chance.
.