brompton - electric or not

[Leonardo]

I’m still studying…

Thank you Miles for your suggestion: a couple of models that you named are new for me (academically: what do you think of the Downtube as a cheaper donor bicycle?), but anyway I’m interested in the Brompton for the folding, that as you say has no comparison.

I have a few questions more, about battery issues…

The power tool battery idea, that Tony Castles tried… Do you think it could be improved using the Dewalt nanophosphate 36V 2.1Ah batteries (the A123 with the very fast recharge)? On the French forum I’ve seen that they can give a 10km mixed range with a Crystalyte hub motor, which has surely higher peak power consumption than the Nano.

On the other hand, would a 24V instead of 36V Nano-Motor have really poorer performances, particularly regarding the hill-climbing? I ask that because I have already the 24V battery of my Lafree and a friend of mine who is interested in the Nano-Brompton too has a couple of 24V batteries for his Flyer.

@ flecc: it may be of some interest for you: a chap of the Italian forum changed the motor of his Flyer Faltrad with the third generation Panasonic motor of his broken Flyer T8. He is reporting increased uphill ability and lower power consumption.

 

[flecc]

@ flecc: it may be of some interest for you: a chap of the Italian forum changed the motor of his Flyer Faltrad with the third generation Panasonic motor of his broken Flyer T8. He is reporting increased uphill ability and lower power consumption.

Thanks for that information Leonardo, it fit's with what I'd heard about improvements to the export motors, illegal in Japan of course. It's a pity that this wasn't done for the Lafree Twist series in the first place.
.

 

[Leonardo]

Will's Brompton Nano-Motor has broken

 

[flecc]

I think this is the problem with that motor Leonardo. There have been many adverse reports online on its lack of reliability, and even that favourable A to B test hinted at question marks concerning it's reliability.
.

 

[Miles]

I’m still studying…
Thank you Miles for your suggestion: a couple of models that you named are new for me (academically: what do you think of the Downtube as a cheaper donor bicycle?), but anyway I’m interested in the Brompton for the folding, that as you say has no comparison.

Thanks, Leonardo, I hadn't come across the Downtube bikes before.

They look quite interesting and not too expensive, either.

The "mini" looks the most suitable - there's not a lot to be gained from having front suspension, with a bike like that.... just adds weight...

I'm planning on electrifying my Brompton, at some stage, but not with a hub motor - the rear triangle will need to be modified, but that will have other benefits, as well..

 

[flecc]

I'm planning on electrifying my Brompton, at some stage, but not with a hub motor - the rear triangle will need to be modified, but that will have other benefits, as well..

Cyclone Miles?

Not the Currie!
.

 

[Miles]

Cyclone Miles?

Not the Currie!
.

No, not the Cyclone or the Sunstar and certainly not the Currie

 

[flecc]

The mystery deepens.

Great, I like surprises.
.

 

[Miles]

The mystery deepens.

Great, I like surprises.
.

It won't be for a while, anyway....... only just started on the present project

 

[flecc]

Ditto!

My latest just started and some way off, but two clues laid in the forum.
.

 

[Miles]

I'll have a hunt - haven't been following everything....

 

[coops]

My latest just started and some way off, but two clues laid in the forum.

More devious fiendishness?! Ok, I'm on the hunt too..! I've a feeling it's going to be tough though: seems to be nothing to go on this time... unless its an update to a modification?! .

Are you upgrading the Twist, flecc?!!

 

[flecc]

Clues/hints numbers 3, 4 and 5.

It's not a bike, it's not a modification to what I've done before, and it's not the Twist.

 

[coops]

Ok, that narrows it down.... and looks like my quota of hints/clues is used up .

Not a bike though?.... hmmmm... thats unexpected... I wonder what it could be!... - hey, does it still have pedals? (i.e. a human-assist-powered "device") .

 

[flecc]

Not a bike though?.... hmmmm... thats unexpected... I wonder what it could be!... - hey, does it still have pedals? (i.e. a human-assist-powered "device") .

No, I leave that sort of thing for Segway to fall over.
.

 

[coops]

No, I leave that sort of thing for Segway to fall over.

Not quite what I meant: I was thinking of the "pedelec kayak" or some kind of hydro/solar-charger, but they're both a bit obvious though by your high standards ... but I'll hunt for the clues rather than guess any more .

I have a few questions more, about battery issues…

The power tool battery idea, that Tony Castles tried… Do you think it could be improved using the Dewalt nanophosphate 36V 2.1Ah batteries (the A123 with the very fast recharge)?

I'm not aware what type of Lithium chemistry the bosch powertool is Leonardo (can one tell by the voltage and Ah figures?) or if there is a specific reason why those were chosen, but from what I've read (and others will know more and hopefully comment too) I don't see why the Dewalt couldn't be used instead: it can be fast charged and should handle the required power output as you say. The Bosch may be very similar or identical chemistry, so I'd check!

EDIT: Except I think the A123 are a little less than the 36V claimed? Check this.
The apparent good long-term performance of A123 at high discharge depths is also useful, though again I'm not aware how the Bosch does in that respect.

Stuart.

 

[Leonardo]

Thank you Stuart.
Someone on the French forum said that the Dewalt are really 33V - I don't know if it is true... anyway one of these batteries was enough for a 7-10 km ride without pedalling with a Crystalyte (408 I think)... I don't know anything about the Bosch battery, may be it is better than the Dewalt.
Anyway now I'm worried about the reliability of the Nano-Motor: Flecc's and yours warnings, A-to-B's question mark and now Will Howard's experience... it is a bit too much: being so far from the designer I cannot afford reliability problems... I still think that the Nano-Brompton is a wonderful idea, but maybe it is better for me to wait a while and see... see Howard's report and may be Miles misterious idea?
In the meantime: does anybody know anything about the Brompton Crystalyte kit - a 209 motor they say?

 

[Leonardo]

Thank you Stuart.
Someone on the French forum said that the Dewalt are really 33V - I don't know if it is true... anyway one of these batteries was enough for a 7-10 km ride without pedalling with a Crystalyte (408 I think)... I don't know anything about the Bosch battery, may be it is better than the Dewalt.
Anyway now I'm worried about the reliability of the Nano-Motor: Flecc's and yours warnings, A-to-B's question mark and now Will Howard's experience... it is a bit too much. I still think that the Nano-Brompton is a wonderful idea, but I can't afford reliability problems being so far from the designer... May be it is better for me to wait a while and see... see Howard's report and may be Miles misterious idea?
In the meantime: does anybody know anything about the Brompton Crystalyte kit - a 209 motor they say?

 

[coops]

You're welcome Leonardo .

Someone on the French forum said that the Dewalt are really 33V - I don't know if it is true...

I've heard that about some of the lithium batteries but I don't recall which... so it needs checking . I remember having no success trying to find out which battery type is used in the Bosch.

Its a shame about Will Howard's motor trouble on the Brussels trip, but good that he was "philospohical" about the outcome .

You certainly find some interesting web pages Leonardo some differences in information though: it is unclear if the C209 motor weight is 3.8kg or 5kg?! Both are relatively heavy (compare Torq/Quando motor weight of 3.5kg including wheel build). Also 10Nm of torque is not very high? (Quando torque @ peak power output is ~ 30Nm!) - Could be just a mix up over information though....

Stuart.

 

[Leonardo]

Did you see Will Howard's "Recap on the performance of the nano Brompton"? (At the bottom of his blog).

I don't understand which kind of motor problem he had exactly... did it break on bumps?

Interesting is his advice of a pedalling sensor and a six gear model: it is as I considered to take the bicycle (thanks to Steven's advice).

I'm surprised of the problem of the front wheel removing, since, as far as I know, front hub motors are simpler under this respect.

As you see I still feel a strong temptation to buy this bike... may be sparing some money with the power tool battery (to use the assistance just for hills) and a second hand Brompton... By the way, if I find one on eBay, is there anything special I should pay attention to? (Beside of feedback and the usual things, I mean).