What happens above 15.5mph?

Electrically assisted bikes, trikes, etc.
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[XAP]Bob
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Re: What happens above 15.5mph?

Postby [XAP]Bob » 30 Aug 2017, 10:35pm

I happen to agree that 20mph would make a more sane limit for existing cyclists...

But for many people, particularly those using a bike for relatively short transport links, the 15mph likitnis fine.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

hemo
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Re: What happens above 15.5mph?

Postby hemo » 17 Nov 2017, 10:16am

Above 15.5mph you go faster :D .
All my bikes have China kits on them bar one which is an s - pedelec.
All the China kits can be manipulated to ride with assistance above the cut off, as long as you pedal well and hard no one is bothered. The only time you will get noticed is if you use a throttle without pedalling or appear to be going fast with only a gentle cadence.
Although the cut off is 15.5mph you could legally play the 10% speed variation as in cars and ride with 17.1mph cut off, the 15.5 is ridiculous and should have been set at 18/20mph in the first place.

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NATURAL ANKLING
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Re: What happens above 15.5mph?

Postby NATURAL ANKLING » 17 Nov 2017, 10:32am

Hi,
Geoff.D wrote:I have little knowledge of electric motors, but I've been enjoying the thread about conversions.

Looking at websites I keep coming across suppliers saying "If you ride above 15.5mph then a motor is not for you",
**************************************
, and steeper than that I get adrenalin rushes right up to 50+.


Steady Eddy :)
Your not female are you?

"Critics of early steam-spewing locomotives, for example, thought “that women’s bodies were not designed to go at 50 miles an hour,” and worried that “[female passengers’] uteruses would fly out of [their] bodies as they were accelerated to that speed”—which, for the record, they did and will not.* "
http://mentalfloss.com/article/67806/ea ... es-fly-out
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skelo
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Re: What happens above 15.5mph?

Postby skelo » 30 Nov 2017, 10:15pm

I am disabled and have an e-assist on my recumbent trike. Simply, when i get to 25 km/h it stops helping, i can get it up to about 28 km/h on the flat - coming down the Cisa Pass in Italy in the summer I got it up to 67km/h before the display started showing error codes. But it didn't need re-setting and started working later in the day after a rest.

Geoff.D
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Re: What happens above 15.5mph?

Postby Geoff.D » 1 Dec 2017, 9:41am

skelo wrote:I am disabled and have an e-assist on my recumbent trike. Simply, when i get to 25 km/h it stops helping, i can get it up to about 28 km/h on the flat - coming down the Cisa Pass in Italy in the summer I got it up to 67km/h before the display started showing error codes. But it didn't need re-setting and started working later in the day after a rest.


Thanks for this, skill. It answers my question. Above 25kph the bike becomes normal, apart from the added weight of the equipment. Before embarking on a winter project I wanted to ensure that the motor didn't add extra drag, as if riding with a brake on.

By the way, after doing 67 down the Cisa Pass, I assume that you're referring to the display not needing to be reset and able to work again after a rest...... and not yourself !! :wink: :wink:

kwackers
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Re: What happens above 15.5mph?

Postby kwackers » 1 Dec 2017, 10:30am

The thing I don't like about the cut off is it is fairly abrupt.
Hard to put numbers on but I think it tails off over around 2-3mph so say at 14mph you get full assist but by 17 you get nothing.

The problem with this I find is I get used to how the bike behaves and mentally I end up with the preconception that it accelerates faster than it really does.
So I put a sudden spurt of acceleration on (say to drop into a gap of moving traffic I'm overtaking) and I'm suddenly hit by a bike that has lost the acceleration it had...
You find you end up watching the speedo more than you probably would like to (I normally pay it no attention) but in the situations when you need acceleration you also need to know how close you are to the limit.

In this the idea that the bike just becomes 'normal' is a bit misplaced, since after riding them for a bit 'normal' is a bike with more acceleration and it can be a bit of a shock when it suddenly doesn't have it.

(As it happens a 'bug' in my controller means you can bypass the speed restriction easily with the throttle and without it the bike is a whole lot more civilised. If you have a C961 LCD try it, I'd be interested in knowing if it's all or just some that have this 'bug').

FWIW, mines a crank driven system and there's no noticeable drag with it off. In fact I knock the assist off for a few miles at a time and use it 'normally' (but only on the way home...)

skelo
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Re: What happens above 15.5mph?

Postby skelo » 5 Dec 2017, 3:06pm

Geoff.D wrote:
skelo wrote:I am disabled and have an e-assist on my recumbent trike. Simply, when i get to 25 km/h it stops helping, i can get it up to about 28 km/h on the flat - coming down the Cisa Pass in Italy in the summer I got it up to 67km/h before the display started showing error codes. But it didn't need re-setting and started working later in the day after a rest.


Thanks for this, skill. It answers my question. Above 25kph the bike becomes normal, apart from the added weight of the equipment. Before embarking on a winter project I wanted to ensure that the motor didn't add extra drag, as if riding with a brake on.

By the way, after doing 67 down the Cisa Pass, I assume that you're referring to the display not needing to be reset and able to work again after a rest...... and not yourself !! :wink: :wink:


Yes, I definitely needed a r're-set' with a couple of large Peroni!- a reasonable reward for the earlier climb to the top :D :D

hemo
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Re: What happens above 15.5mph?

Postby hemo » 5 Dec 2017, 3:40pm

Quite a lot of lcd's (dependent on make/model) can simply be reprogrammed by changing parameters in the on screen menu's a few seconds of adjustment can often soon have you whizzing along above the 15.5mph cut off. The downside is the bikes range is less as you are using a higher speed cut off or no cut off at all.

The C961 and other BBS LCD's can all be adjusted for speed none of them have bugs, it depends on the seller who supplies the kit as a third party vendor. Some reprogramme the controllers as out of the factory settings are very conservative to prevent warranty issues. I use a programming lead and free download software to programme my BBS01, if I want longer battery range then I factor in lower power usage (amps) and keep current ( rpm/ cadence) if I am riding in hillier terrain I can up the power.
Last edited by hemo on 5 Dec 2017, 3:58pm, edited 2 times in total.

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[XAP]Bob
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Re: What happens above 15.5mph?

Postby [XAP]Bob » 5 Dec 2017, 3:56pm

kwackers wrote:The thing I don't like about the cut off is it is fairly abrupt.
Hard to put numbers on but I think it tails off over around 2-3mph so say at 14mph you get full assist but by 17 you get nothing.


I suspect that behaviour varies significantly between models. I don't really notice an abrupt cutoff, but then I might just be getting less power at 10-14mph... Just don't know do we ;)
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

kwackers
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Location: Warrington

Re: What happens above 15.5mph?

Postby kwackers » 5 Dec 2017, 4:54pm

hemo wrote:The C961 and other BBS LCD's can all be adjusted for speed none of them have bugs,

OK, so I'm aware of the menus and all the options, changing the speed is easy.

But, if you leave the speed alone (25kph) and set the assist at 3 or greater (I've set it up for 5 levels) then it cuts out at 25kph - unless, you push the throttle fully open in which case it doesn't cut out at all - at least up to 55kph which is the fastest I've managed on the straight with the wind behind me.
I know it's helping because if I release the throttle then I can't hold the speed, push it again and the speed creeps back up.

That seems like a bug to me. Whilst I haven't bothered reprogramming the drive unit I have fiddled a lot with the various options in the menus so perhaps I've 'broken' something?

Reprogramming the drive is next on my list. On lower levels of assist the cadence cut off is too low (thinking about it, it also ignores the cadence cut off when the throttle is held open).