Kits

[Jeremy]

Nick,

My 'bent only has a 20" front wheel, so the hub is a relatively large proportion of the overall wheel. The wheel has to be radially spoked, as the spokes are so short that a crossover spoke pattern would be pretty near impossible. As an idea of the relative proportions, the 405 hub diameter is 195mm, the 20" rim diameter is really only 406mm to the tyre bead.

The TongXin hub is much smaller, only 110mm diameter, so as well as the lower overall weight it would give a massive reduction in angular momentum, very significantly affecting the steering response issues I've found.

The steering/balance effect from the added front wheel weight is very noticeable, perhaps due to the different response that a SWB 'bent has when compared to an upright. Because of the lower C of G, a 'bent is already less stable than a conventional bike, so any variation in steering/balance response tends to be amplified.

I dare say that I can get used to it, just as I got used to the very different "feel" of the 'bent when I first got it.

Jeremy

 

[Tiberius]

Ok Jeremy,

I was thinking in terms of 26 or 27" wheels because that's what I'm used to. I also had mental picture of the recumbent as a 3 wheeler for some reason, but if its a two wheeler than the whole dynamics is both different and more important.

Nick

 

[Canadian Cadence]

Not just A to B, and David Henshaw's many years of cycling experience means he can identify a poorly set up bike more easily than most people. The 250 watt one is a much weaker hill climber than the 350.
.

My problem with the A to B rating was that it ranked the 250 lower than the panasonic drive bikes ......something I did not find when testing the bikes on the hills in my area.
There is no question that the 350 is stronger than the 250 in all areas.
I know the frustrations Steve is having trying to pick a kit for his bike .....I went through the same process a few years back.
I was not even thinking of a kit until I tried one of the first 350's when they arrived in May 2006. I bought the kit that day.
I just have not found any reviews and comparisons of the 350 and this is what I find so frustrating because I know it is a top notch system. Most use the 250 reviews and apply them to the 350 saying it is weak hill climber.

I did notice that a 350 Bionx on a Hercules bike won the hill climb in Germany last month.

The 350 is a very strong system and the ability to ride your bike unassisted because of the low weight and little to no friction is a real bonus.

One other thing to note. You can order the 250 with the throttle as an option (standard on the 350) The throttle will give more boost when hill climbing even when in assist 4.
The console of the Bionx is real gem. Giving all the diagnostics and the ability to de-restrict.
I have stated earlier that I have not noticed any loss of power with the lithium battery on the 350 and it is still registering 41 V ( system will be 2 years old in May )
Good luck in your quest Steve.

 

[flecc]

I agree, A to B do have a strong bias in favour of the Panasonic system, but I think that's in part based on ultimate hill climb ability. Driving through the gears means the Panasonic system will handle just about anything, albeit only slowly on steepest climbs. That's certainly not true of the 250 watt BionX, though what it does, it does much quicker.

A to B are primarily reporting for the UK market, and very steep hills are common here on our historic no-engineered roads, hence their liking for drive through gear systems. Again you're certainly right about the BionX 350 watt version's superiority, but it's illegal here, so can only be privately imported and used with a degree of risk. That makes it impossible for our publications to properly report on it.
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[giguana]

I have a 406 being posted today, if you speak Polish you can probably get a 407/4011 dual gear motor from the Polish crystalyte representative (from their website).it sounds like the 406 should be ample for hills from what you say.

Jeremy- it sounds like you could do with putting the voltage to 24V and finding a more gradual throttle. do you mean that the controller kicks in too fast at speed or that the start from standstill is sudden?

The throttle is a potentiometer, once I know the resistance I am interested in making a custom throttle so that I pull/push along the handlebar to engage speed with a slider/fader mounted with a spring, because I have RSI and rather avoid flexing my wrist back and gripping for long periods. like this I can choose a high-quality potentiometer either exponential or linear resistance, ...exponential would give a very gradual acceleration. As long as it's reliable and ergonomic with the handlebars it should be okay.

it has to be mentioned also that rear wheel solutions are safer generally depending on the road slipperiness and the amount of weight on the back, and make for better hill climbing.

 

[Jeremy]

The throttle isn't a pot, it's a Hall effect device. From what I can gather, virtually all the Chinese thumb and twist grip throttles are made this way.

It's a bit non-linear, as nothing happens for the first 20% or so of movement, then the power comes in with a bit of a kick.

I need to look at the way the controller responds to the throttle voltage to get a better idea on the best fix. I could easily reduce the voltage (which I may well do anyway) but I like the idea of lower losses from running at 48V with proper control.

From looking at the Crystalyte controller design schematics, it seems that the throttle input is a motor speed control input, with the controller having a built-in throttle ramp-up delay. What I really want is a combination of a speed and torque control input, so that the throttle command is interpreted as a power demand, rather than a speed demand. I'm sure this would make it feel a lot better and would probably resolve the wheel spin problem I have with the 405 at the moment.

Out of interest, how much was the hub from Poland? I have some business connections there, so might investigate further.

Jeremy

 

[giguana]

Rowery elektryczne, napêdy elektryczne do rowerów
he told me to send an e-mail on the phone but communication was hard and I sent a couple of e-mails including one with Polish translation but I didn't get a reply. I don't understand very well because he has a web page in English but I think he hasn't really done any mail sales before, but the motors are very cheap and some of the better ones you can get because they are geared with two torq levels, the basic kits with motor controller breaks and throttle is quoted at 210gbp including fitting. I know a girl with a sexy voice who speaks Polish hopefully I can try one out sometime.

thanks for explaining the throttle I was trying to figure it out I will see what info I can get hold of.

 

[Jeremy]

Thanks for that, I know a little Polish and am planning on going there again some time after Christmas, so I may try and contact them.

The Chinese throttles all seem to be very similar, I have two, a twist grip and a thumb throttle, bought from different vendors, that both look to work in the same way and give the same sort of output voltage. The throttle movement seems to move a magnet relative to a linear Hall effect device I believe, which should make for a very reliable sealed unit. This produces an output voltage of typically 1 - 4 V or thereabouts to drive the speed input on the controller.

Jeremy

Edited to add:

I've just looked at that Polish web site and don't recognise the controllers shown. They don't look like either of the two types of Crystalyte controller I've seen, so I suspect they may be from another vendor. The motors are definitely Crystalyte ones though.

 

[flecc]

These Hall effect throttles come in two types, one with a bar magnet running alongside a Hall device, the other having a magnet at each end of rotation, the magnetic field at the Hall device "gradually" transferring from from one side to the other.

In practice when trying both types on a bike, they are both as fierce acting, almost like a switch. With simple rotation it's unavoidable, given the non-linear nature of magnetic field strength with distance, but if a variable cam ramp could alter the side distance in and out by changing amounts throughout the arc, it could be made quite linear.
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[Steveu]

BionX

Thanks for the further info. I'm still leaning towards the BionX 350 - but bit surprised to be quoted $325 for shipping to UK (from Nycewheels in NY).

I undersatnd that the legal situation is not simple. I guess the 350 is more powerful than the UK rules allow on the road but does this still apply if it can be switched to lower assist (I understand that different levels of assist can be set) or does the mere capability of higher power in make it technically illegal?

I've read about the way of de-regulating an Ezee Torq simply by disconnecting a wire. If a regulated and de-regulated state (eg for on road and off road) can be easily selected by means of a switch, i wonder how the law would see this? But until they have speed cameras capable of automatically detecting the the power capability of a passing bike, i've a feeling that this probably all somewhat academic

Steveu

 

[Jeremy]

I buy a lot of stuff from the US and $325 for shipping from the East Coast is way OTT - you are being ripped off, big time. The shipping cost from Vancouver, for a motor, wheel, controller and throttle, was CDN$106, using TNT (who are not the cheapest).

Shipping via the USPS is the cheapest usually, but provides little protection for high value goods and can be slow. It's also weight/size limited I believe. Fed-Ex is OK too, although similar in price to TNT. I'd steer clear of UPS, twice they've hit me for excessive import handling fees.

My advice would be for you to set up an account with someone like Fed-Ex and get the package delivered collect - meaning that the vendor tells you when it's ready and you task Fed-Ex to collect from them. This is reliable, provided that the vendor is in the Fed-Ex collection area.

You will most probably get stung for import handling fees, VAT and duty at the UK end. If you get the vendor to declare a low value, then the VAT and duty will most likely be reduced, BUT you run the risk of under insurance if the package is lost or damaged in transit. It's also technically fraud...........

Jeremy

 

[giguana]

check usps.com for reference, 40lbs is about 200us plus insurance, I'm getting 9kg from Canada for about 145us by TNT...it doesn't really make sense to have batteries flown to America from China and from America to the UK...mind you if it is UPS you don't have to worry about impounding at duties.

thanks I will try and figure out this Hall device it sounds fascinating...

 

[Jeremy]

I agree it is daft to ship things right around the World, but for some reason this sometimes seems to be the only way to do things! For a wheel with 400 series hub motor, controller and throttle, the USPS shipping cost would have been about USD$90 as I recall, although it would have been slower then TNT perhaps (TNT took just over a week). I found TNT to be a pain at the UK end, they insist on you sorting out customs clearance at Heathrow, then charge you for the privilege............

Good luck with the throttle experiments - I've been reading up on a mod to add load sensing to the controller, so that the throttle control behaves more like a power demand control. I'm going to measure my spare throttle response tonight to see how I might change it along the lines that Flecc has suggested. It might be a good start.

Jeremy

 

[giguana]

I have written to the guy from ebike, he says-

The hall sensor throttle is far more immune from water damage and
wiper wear. However, if you want to install a potentiometer based
throttle, you can totally do that too .The active signal range is
about 1.2 to 3.6V, and you are provide with a Gnd and 5V to generate
it from.

so if it's possible to find the right kind of potentiometer there could be all kinds of possibilities...

 

[flecc]

so if it's possible to find the right kind of potentiometer there could be all kinds of possibilities...

An effective and reliable way to do this is with a rotary switch, I built in a 24 step volume control into my Hi-fi amp in this way.

On a throttle you'd probably only need 12 to 15 steps wired with a chain of resistors across the contacts to give the ascending resistance and smooth progression. A make before break switch would be best, but not vital.

You could either use a proprietary contact rotor from a switch large enough to have a handlebar size hole cut in the centre, or have a switch at 90 degrees driven from a bevel gear.
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[giguana]

that would sound long-lasting and water resistant. also there is a possibility of a string pot and even a ribbon controller which is like a flat band that changes resistance when you press a finger across the length. it's even possible to use a thumb throttle tied to a wire like a string pot although a real potentiometer sounds more precise. do you know how many Max KOhm for the throttle? I think I would have to measure the amps of the 5V.

Jeremy-apparently the drain brain lets you set limits of voltage, ampers, speed, to simulate a slower motor as well as calculating distance and kilometres per hour and amp hours used by the battery...
The Cycle Analyst Homepage - Ebike Amp-Hour and Watt Meter

 

[MaryinScotland]

Sounds like the choice might be between the BionX 350 and the Heinsmann

Steve, sorry to come in a bit late on this, but I did use a Heinzmann for a couple of years. (You'll find it on the "Reviews" page of this site.)

Some people have described Heinzmann as "noisy". I had the 200W road-legal front-wheel motor, and although it made a slight whine, I felt it was fairly quiet. Pedestrians on a shared path wouldn't hear me come up behind them. But that motor has nylon internal gears; some of the higher-power Heinzmanns have metal gears, and make a more obvious sort of "buzz".

I gave up on the Heinzmann because of the weight - I have to carry my bike up and down 2 floors, every day I use it. I'd fitted the Heinzmann to a rather heavy steel-framed Dawes hybrid, and it got too much for me. I've now got an Urban Mover which is several kilos lighter. I still miss the Heinzmann throttle control, though, that would let me opt for no power, slight power, all-out or anything in between. The UM pedal sensor is "all or nothing".

I look in on the Heinzmann web site now and again, in the hope that they will produce a new lightweight complete bike. But even if they did, all their models have the batteries on the rear rack, which I never liked. I really believe that the battery weight needs to be low and central.

Mary

 

[Steveu]

BionX PL350

At long last, I'm about to summon up the courage to send lots of money to the USA for a BionX. My recollection is that all/most BionX users on here recommend the 350 with a Li-ion battery as this set up does not suffer nearly as much with the problems reported with Li-ion batteries on other motors. As Li-ion costs another $360 more than the NiMH option I just wanted to check if anyone has other views on this.

Thanks

Steveu

 

[flecc]

Everything I've heard on this indicates that the only problem is the price Steve, but since the life could be much greater than the troublesome ones, it could easily be as cheap or cheaper in the end.

The only medium or high power e-bike motors that I would consider using with Li-ion at present are the Panasonic or BionX units because their power and battery management systems are so good.

The occasional very low powered bike like the Powacycle which didn't work the battery much would also be ok.
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[Steveu]

Thanks flecc

Flecc

Thanks for the prompt reply (and very helpful as usual).

Steveu