Fastest climber?

[eddieo]

Brucey Baby........From a totally non tech perspective what puts me of is the weight, as a motorhomer I am always looking for a well spec'd lighter E bike.

Like you said, until you see and try its hard to tell, but the colours look naf IMO. A bike is black...end of

But I like the look and straight frame city and sport tourer style bikes. But you are so way behind in design these just look like loads of other stock Chinese bikes....sorry but nothing really new

most of us want a stock looking lightweight bike with battery within the triangle, at least I do! lol and why I am now prepared to wait for a wisper 1006, OR a BionX or wisper kit maybe the answer.

a stock looking bike is easier to maintain, LBS dont laugh at you when you bring them in.

Wisper are so far ahead they need not worry, because they invest and are always pushing with new ideas. I noted your comments re 3 hub gears and I kinda wondered myself regards this, as the difference between a 3 & 7 is not that great......But wisper Know what they are doing, and are going for every area of the market. and you have to halt the spec somewhere I guess or push the bike beyond its price point.....

I wish you luck, and if you price the bikes right and they are as good as you say you should do OK

 

[Mussels]

Branded parts - most of our parts are branded and would be instrantly recognised - happy to elaborate if required. Most of our buyers are not that interested we find, and the bike brochure is targetted at buyers who are not specialists

"Six gears is cheap."

I am learning loads and this forum is really helping me understand some of the issues. Please bear in mind that at Berprint I am the marketing guy, not the technical expert - except perhaps on batteries.

I have learned loads about gears today. Thank you to flecc for stimulating the debate, and for Mussels driving me to challenge our designer, and for Eddieo's reminder (which was too late - bikes had been ordered before then.... but thank you anyway)..

My concern - perhaps as the tidy minded scientist rather than the expert biker - is to ensure the gear ratios are correct and cover a wide enough range.

Looking at the industry standard Wisper City in this part of the market, we see a 48 tooth crank and seven sprocket mega range Shimano (34 to 15 teeth) as described by flecc. Unless I am missing something, this means a ratio of 1.4 at low gear, rising to 3.2 at high gear.

I compare that to our typical configuration on our City which has a 46 tooth crank and a six sprocket Shimano (28 to 15 teeth) which means we have a ratio of 1.6 at low gear, and 3.1 at high gear. For those doing a large amount of hill climbing, or for elder clients who tend not to go fast, we offer a 38 tooth crank giving 1.4 and 2.5.

Our monuntain bike is higer geared with a 48 crank giving 1.7 and 3.2.

I do not think these solutions are 'cheap' - more like 'comprehensive'.

But come on guys, this is the knock Bruce 'open season' Please let me know if I am blowing bubbles!! If I am wrong, please tell me....

I find the Wisper 905 gears are inadequate and I dislike the megarange freewheel, I think the only one that has got it right is Ezee as long as their freewheel works well. I have a 14-28 freewheel fitted at the moment and the range of gears is poor enough to keep me looking for a different solution. The ratios may look similar on paper but it can have a big effect on the feel of the ride.
My statement about six gears being cheap was based on impressions rather than fact, it might just be me.

 

[Wisper Bikes]

Gears

Hi Andrew

Would a larger chain wheel do the trick?

We use a 54 on the tourer, I am sure I could dig one out for you.

All the best

David

 

[flecc]

I compare that to our typical configuration on our City which has a 46 tooth crank and a six sprocket Shimano (28 to 15 teeth) which means we have a ratio of 1.6 at low gear, and 3.1 at high gear. For those doing a large amount of hill climbing, or for elder clients who tend not to go fast, we offer a 38 tooth crank giving 1.4 and 2.5.

Our mountain bike is higher geared with a 48 crank giving 1.7 and 3.2.

These are well short of 200% gear range though, and as said, 250% is desirable as a minimum for selling throughout the UK. Even the Shimano Nexus 3 speed hub gear has a 200% range. From your examples:

City: 1.6 to 3.1 = 187%. Top gear inches = 80

Hill climb version: still 187% range. Top gear inches = 66

Mountain Bike: assuming same freewheel 187%. Top gear inches = 83

These gear inches explain why you find the ratios adequate for climbing, the top gears are rather too low, only the mountain bike's top gear just about acceptable. To avoid very high pedal cadences top gear needs to be above 84", with around 90" or more desirable.

As things stand, the cadences at 15.6 mph in top gear are:

City: 66

Hill climber: 79

Mountain bike: 63

One and three are on the fast side for many e-bikers, for example the majority of owners of Panasonic powered bikes finding the 65 cadence enforced by legality on this system far to fast, often describing it as spinning like mad.

The 79 for number two is more like a sport rider's competition cadence, far too fast for the market it's aimed at.

In all cases, anyone wanting to pedal to speeds well above the assist limit when conditions are favourable will have their legs spinning too fast for average riders. For example at 20 mph the cadences are:

City: 85

Hill climber: 101

Mountain bike: 81

getting on for two turns per second on the hill climber.

I'd regard my bike's gearing as just about sufficient in my hilly area, though I'd prefer a wider gear range. The gear range is 262% with a 35" bottom gear, 92" top gear, cadences 57 at 15.6 mph and 73 at 20 mph.
.

 

[Andy_82]

% gearing

These are well short of 200% gear range though, and as said, 250% is desirable as a minimum for selling throughout the UK. Even the Shimano Nexus 3 speed hub gear has a 200% range. From your examples:

City: 1.6 to 3.1 = 187%. Top gear inches = 80

Hill climb version: still 187% range. Top gear inches = 66

Mountain Bike: assuming same freewheel 187%. Top gear inches = 83

These gear inches explain why you find the ratios adequate for climbing, the top gears are rather too low, only the mountain bike's top gear just about acceptable. To avoid very high pedal cadences top gear needs to be above 84", with around 90" or more desirable.

As things stand, the cadences at 15.6 mph in top gear are:

City: 66

Hill climber: 79

Mountain bike: 63

One and three are on the fast side for many e-bikers, for example the majority of owners of Panasonic powered bikes finding the 65 cadence enforced by legality on this system far to fast, often describing it as spinning like mad.

The 79 for number two is more like a sport rider's competition cadence, far too fast for the market it's aimed at.

In all cases, anyone wanting to pedal to speeds well above the assist limit when conditions are favourable will have their legs spinning too fast for average riders. For example at 20 mph the cadences are:

City: 85

Hill climber: 101

Mountain bike: 81

getting on for two turns per second on the hill climber.

I'd regard my bike's gearing as just about sufficient in my hilly area, though I'd prefer a wider gear range. The gear range is 262% with a 35" bottom gear, 92" top gear, cadences 57 at 15.6 mph and 73 at 20 mph.
.

Hi Flecc,

I'm fine with ratios from Bruce but can you tell me how do you calculate the gearing in % ???

Which cog do take to which one?

 

[flecc]

On derailleurs it's very easy Andy, just divide the smallest sprocket into the largest sprocket of the cassette/freewheel and then multiply by 100. Example on a 14 to 34 tooth freewheel:

34/14 = 2.43 x 100 = 243%
.

 

[Andy_82]

On derailleurs it's very easy Andy, just divide the smallest sprocket into the largest sprocket of the cassette/freewheel and then multiply by 100. Example on a 14 to 34 tooth freewheel:

34/14 = 2.43 x 100 = 243%
.

That is what I suspected how you do it but was not sure in 100%, many thanks Flecc

 

[rsscott]

All,

This forum is not the place for trade disputes, please take all further discussion and resolution offline.

Please continue with the original topic of this thread.

 

[Mussels]

Hi Andrew

Would a larger chain wheel do the trick?

We use a 54 on the tourer, I am sure I could dig one out for you.

All the best

David

Thanks but I deliberately put a smaller chainring on to make climbing hills easier, My bottom gear is now the same as when the bike was new but I haven't got the 10 tooth step between 1st and 2nd gear*. Having the right gears at higher speeds is less important for me than having the right gears for when I'm going slowly.

* After swapping the 14-34 Megarange freewheel for an evenly spaced 14-28 freewheel.

 

[Wisper Bikes]

Chain Drive

Thanks Russ!

Andrew, if you need a smaller chain drive I am sure we can find one for you.

All the best

David

 

[jerrysimon]

This thread is a little fiesty

I find the three hub gears on my EBrompton more than sufficient, but then I live and ride in Cambridge.

Regards

Jerry

 

[morphix]

I can just see it now

cycling down the main street at a steady 10 mph

attractive young woman walking down the pavement, gives you a wee smile and the bike takes off like a scoulded cat

hahahaha

 

[Polar753]

This thread is a little fiesty

I find the three hub gears on my EBrompton more than sufficient, but then I live and ride in Cambridge.

Regards

Jerry

I ran away, turned into a bit of a playground,

People with commercial interests should be very careful about slagging each other off in public. Just my 2p.

Lovely sunny day today

 

[poppy]

The trade-off is that starting an ascent from a standstill requires more human input and feels much less "natural" than a drive-through-gears motor (which, by the way, also contain an internal reduction gear mechanism).

Cheers, Dan [

That´s exactly what happened to me when I test rode an Emotion Urban 700 which has that kind of system! Even on the flat, the starting was more difficult and irregular than the non hub Emotion.

 

[ELECTRIC AVENUES]

Crytalyte 5304 with a Lyen Edition controller, 72v @ 65Amps and 20Ah of A123 will climb just about anything.

 

[NRG]

...and be just about the heaviest and hardest thing to pedal when the battery runs out! .