A2B GEN2

[westoe]

Hello,
I am at the thick end of my Fifties having cycled all of my life around the beautiful hills and roads of Northumberland in the most northern part of England.
I have decided to treat myself to an ebike and decided on the A2B Metro Generation 2. which I fell in love with as soon as I saw it - not knowing it had been on the market for some eight years. Ebikes are not that big here in the UK and after only doing 37 miles I really have turned some heads as I rode past.



I would be grateful for a few bits of advise if possible from the many experts on this site if you would be so kind.

As mentioned I have just covered 37 miles on the bike and still had six bars of battery available on the speedo:



The actual battery on the bike is different from the 36v 11.4 ah advertised and I wondered if this is an improvement and a bonus to me.



The battery took three and half hours to fully charge from this state.
I noticed that whilst riding the bike if I accelerated the bike fully on the battery and moved up the gears as I pedalled; after about twenty seconds or so I could slowly decrease the battery on the accelerator to near two bars on the hand grip and the motor would settle at the speed I was pedalling which was around 20 - 22 MPH. I could then pedal harder to increase speed and the motor would still assist my efforts making it very easy to gain more speed and maintain a very decent speed on such a heavy bike - I was amazed.

When I got home I looked the bike over and noticed the crank was of a solid design - not like other images I had seen of the A2B Metro Gen 2.



and the reverse side has a wire coming out and away into the frame.



Does anyone know what this is and what it does?

I also thought the company had replaced this kind of rear shock with another design?



and lastly (phew I hear you all groan) what is this all about:


The internet alludes to it being a German firm which has since gone bust.
Sorry for so many questions on my first post - I am so impressed with this bike I am off to put a coat of Armor All on the paint work to keep it looking pristine.......

 

[agniusm]

Very nice bike mate. We dont have them here bit I saw one in Malta and it looks very good. I think that is a pedelec sensor on your photo. Enjoy the bike!

 

[westoe]

Thanks for the info agniusm.

I have Googled "pedelec" and by jingo you are spot on.

I now need to find out how to set this mode electronically on the bikes display to pre-set the function. Or, I need to find out if it is just a case of a little throttle adjusted to the power at the pedal that I have discovered by chance - is the answer.

All in all the bike has surpassed my expectations and is a joy to ride - eating up the miles and making me want to get out and cycle like I used to in my younger days.

 

[agniusm]

I think in EU it means that motor cannot engage if you are not pedaling Who cares

 

[paul8bee]

I have been riding the a2b for the last 8 months. Good solid machine. I only ride 8 km per trip, but have logged 6500 km so far, in all kinds of weather. I cut the wire to the pedal sensor, (shown in your picture) because all the grit from all the rain riding ruined the sensor. I like it better without the pedal assist sensor. Biggest problem is the flat tires. 6 so far. I have some Shinko sr-714 motorcycle tires I am going to install this week, they are 4 ply and am told that flat tires will be no more. At 225 lbs, I doubt if I could get the mileage that you did. I would be lucky to get 20-25 km from one battery, (I only run the frame battery). This bike was not built for pedaling. I find that the bike is more like a scooter than a bike. But I am very happy with it so far

 

[westoe]

Hello Paul8bee.
I too have had trouble with the PAS on the Metro after a particularly wet spell of weather.
I use the bike every week day to commute 5.5 miles to work and back so I am only adding 11 miles a day which gets me two and half journeys on one charge.
One day I started my commute and once the bike reached the normal 16.9 miles an hour the PAS failed to kick in and by do you know when it is not there; keeping the bike over the throttle limit of 16.9 was damned hard work.
When I got the bike home and began to dry it off I noticed a rusty brown drip coming from the back of the PAS unit.

So I stripped the unit off the bike and opened it up.

It was full of moisture which had tracked across the sensors and the circuit board.

I cleaned everything up and dried it out with a gentle heat for an hour or so.

Assembled the unit and fitted on the bike and after a month the PAS has worked perfectly.

Riding on the flat I was managing around 21 - 25 miles an hour with the PAS; but I have removed the derailleur and gears and fitted a single speed 16t freewheel cog which has revolutionised the ride; made it silent whilst pedalling and given the bike a solid and responsive feel but has limitted me to 17 - 21 miles and hour at the moment............54t or 56t front crank might be on my shopping list.

 

[pdarnett]

I went to a 53 tooth and never looked back.


Took some hunting to get a chainguard though!

 

[westoe]

I must admit I like the look of your 53t chain ring without the guard - really, really nice.

The PAS unit looks cluttered on mine compared to the clean lines of your set up.

I have just purchased a 54t chain ring from Hilary Stone - he has a sale on at the moment - so should see a difference once that is fitted.

I worked out that with a 54t chain ring I should travel 5.8 yards with every revolution of my pedals:

WHEEL SIZE (TIMES) CHAINRING (DIVIDED BY) REAR COG TEETH SIZE (TIMES) Pi (3.14) = INCHES TRAVELED (DIVIDED BY 12) = FEET TRAVELLED

So for my Metro set up:

20*54/16=67.5
*Pi=211.95
/12=17.6 FT
/3=5.8 YDS for every revolution of the pedals

 

[pdarnett]

Mine was an original US version Gen 1 so no pedal assist, just throttle. I've since designed a nice dashboard and fitted a pedal sensor as I'm used to having a pedelec! dashboard demo is here https://www.youtube.com/watch?v=sxQB6dYEl3w

Next modification will be a proper torque sensor like the BeamTS system, one that accurately measures chain tension. The chain guides are already there, be a shame not to utilise them!

 

[westoe]

That look so cool pdarnett, did you design it yourself?

How do you set the amount of assist - is that something available on the Gen1 bikes?

The Gen2 display is nice but very limited. I have two batteries on the bike - a frame and rear but can only get the display to show the battery level indication for the original rear supplied battery. I have to set the trip for the frame battery to give an indication of the amount of miles left in the battery.

 

[pdarnett]

I designed it myself as there's no pedal assist on the gen 1 or any kind of dashboard. Next job is to move from simple pedal assist to building an actual torque sensor. i.e. if you're having to push harder the throttle will ramp up to meet you so to speak. Still working out the how to detect though!

 

[westoe]

Well, with the rainy North East of England weather I am finding myself having to strip the PAS unit on the crank at least once a month to dry and clean the circuit board and sensors.

My question then is quite simple.

Can I short the connector from the controller to isolate the PAS at the crank to enable the assist to be "permanently" on as far as the controller is concerned.
My fear is that I might damage the controller in some way or will this idea simply not work.

Thanks for any help or advise anyone can offer.