A2B Metro - www.ultramotor.com - Video Page4

[deepfraught]

Here is another little interesting snippit I found online while doing more research. Seems some Metro's have an OffRoad-Boost button right next to the throttle.
Anybody know if that is a feature of the EU/pedal assist bikes? Or if controler just dumps more unregulated amps into the motor?

Source http://crave.cnet.co.uk/gadgets/0,39029552,49302308,00.htm

In england and probably the rest of the EU the A2B Metro is limited to 250W unless you press that "off road button" then it becomes a normal 500W A2B Metro.

I'm in Aus and don't have that button at all... GPS confirmed ~25kph as stated in the 200W 25kph limit owners manual.
Does anyone have photos of their relay box wiring with that "offroad switch" traced to where it goes?
I just checked and didn't find any obvious connector that plugged or unplugged that changed the wheel speed.
Just the LED lights and throttle in black plugs, battery relay and battery wires in white plugs, black/grey plugs, and the brake kill switch signals white/black. I unplugged the front brake kill switch for burnouts
I'm just stumped for de-restricting it now, hopefully something on the controller board inside... but still a pain.
My relay box said model C on it, in case othershave the offroad switch wires additionally in there.

[Ypedal]

My Metro does not have that button either.

I"m fairly sure all the settings are programmed at the controller and would require opening the motor to mess with... If you bother un-lacing the wheel, opening the motor ( press fit, not screwed. ) you may as well cut the internal controller and run external wires to a 3rd party controller.. the soft start and power limits being removed, the motor would end up heating more and would be prone to controller failures if left inside the hub..

If i dont sell my Metro soon, it's getting modded the moment something fails..

[deepfraught]

Yeah it's a small shame. I've hunted through the wiring, but no luck finding a harness plug to bridge for the European offroad button that I hoped for.
15mph looks terrible on paper for all that weight and cost, but wasn't as bad on the road after a test commute day Friday, finishing trip about the same time as most faster road bike commute rides.

I've only ever shattered that time riding the Norco fast for a battery test, after peak hour on a Friday evening, home by dusk, low pedestrian traffic on shared paths, got home in 35min with 32mph top cruise speed only reached a few times. That wasn't any real cycling though and I didn't enjoy it as much.
I did enjoy the cycle challenge of the stock A2B. I rode home with new wide panniers carrying some new cycle stuff that had arrived with the panniers and had been sitting at work for a couple weeks, trickling it home in spare space on the road bike backpack. Since the A2B Metro has rear suspension, I used the backpack rack bungee cords under tension to the swingarm as pannier stays, it did a pretty good job to get me home safe, only one bit spot of rubbing wear.

I don't mind the soft start, I'm not wanting to wheelie it like the Norco I was still able to cross the road quickly enough with or without pedalling to slip through gaps in traffic. Trying to figure out a removable auxillary battery option with either a 7Ah 36V watter bottle mounting type I have, or 10Ah 36V seat post type. Both options taking up luggage space with current ideas.
Has to be removable so I can ride on auxillary B batt, charge it at work, ride home on frame A batt and charge at home.
Factory option B batt would be ideal to keep more luggage options and convenience... but $650+ ouch. I emailed Ultramotor asking if any refurbished or unservicable B batt's, but no reply.

I was wondering what B batt with +12-18V (<60V) would do for top speed, if controller didn't drop current to keep the 15mph speed limit.
I saw mention of 62V on controller caps.

[Gregor]

Please excuse me if I have skipped over this somewhere in the 14 pages, but hasn't anyone run this stock motor/int. controller at 48v for any extended period of time yet? If it's still the slow start, that's OK, but it would be nice to know if this motor could be put on a much lighter wt. frame with maybe 2 inch wide tires and get some good performance out of it? I have purchased a wheel (rear) only and it has just been sitting, even though it is fairly easy to hook it up to any hall throttle and a battery and I'd be good to go. I just don't want to put the time in to relacing it and find the right frame to put it into. Any input would be appreciated, thanks.

[Ypedal]

The whole soft start makes it not worth the hassle and potential over-heating of the internal controller at 48v imo.

Yes, it works.. but no it's not right.

This thing really needs to be opened up and gutted.. The motor has plenty of potential as a 3000~5000w rig, but needs a proper external controller.

[deepfraught]

Alternatively if you pull it from the wheel to put it into a bigger 26" you'll get higher top speed too.

[Gregor]

I'm thinking 26 inch wheel (the stock oversize tire is 22 inch on a 20 rim) whould add 20% to the top speed. If you take perhaps 12s lipo (44v)-- about 20% more volts, and get a frame that is 20% lighter, it could add up to a decent, stelthy type of a project--does anyone happen to know if the rear dropout width is 135mm?

[deepfraught]

It is 150mm dropout. I had a tape measure by the bike last night, forgot to post though.
Spacing of mechanical BB5 caliper looks like enough for hydraulics, versus my 9C with 135mm dropouts that needs brake rotor spacing out from the motor.

[Ypedal]

Ran capacity test on the A battery yesterday.

AB-2012-capacity.JPG (44.36 KiB) Viewed 1137 times

And used it today to get a few battery packs from the post office !

[joepah]

On newer A2B Metros the controller was moved from the motor hub to the bike frame, since that was a source of numerous motor replacements. My motor has been replaced 5x in 3 years for that very reason.

So someone could modify the controller to get the American 500W+ motor power or more with an on demand power button.

[joepah]

The whole soft start makes it not worth the hassle and potential over-heating of the internal controller at 48v imo.

Yes, it works.. but no it's not right.

This thing really needs to be opened up and gutted.. The motor has plenty of potential as a 3000~5000w rig, but needs a proper external controller.

How long have you own your Metro? Over heating was a HUGE PROBLEM for early Metros... My Metro hi temp t/c's would trip after 20 or so miles, and it would take a long time to cool After they started using higher temp t/c with a soft start, no OT trips!

[deepfraught]

joepah do you have any of the old motors/controllers that were replaced? I'm looking for one to have in hand to compare against the Australian 15mph limited version I have here, in case it's a jumper position on the board. Failing that, a working USA one in hand would mean plan B swap while I have the motor open.
I upped my front sprocket from 42 to 48, and am now pedalling 22mph cruise with motor not doing as much (speed told to me by two road bikes drafting me on two separate occassions who wanted to know more about the bike

I've loved it so much now I've commuted on it for 8 days in favour of my custom parts bin special flatbar road bike that I preferred over all others for fast convenient commuting.
First day with the 48 tooth sprocket on front, I had 2 road bikes drafting me run up my A2B Metro arse when I stopped at a break in cycle path to give way to a 2T SUV entering T-junction.
Being such a tank A2B Metro didn't budge while on the brakes near stationary as first guy hit, only harm was derailleur tweaked lost top gear til next stop when I slackened off the cable at shifter a bit.
It was small vindication for feeling bad a week earlier on my road bike giving piece of mind to an intersection bike queue jumping arse hugging drafter.

The worst thing that slows down the A2B Metro the most I've found is it's total opposite of "stealth", it's obvious under paint decals that give it away, attracting lots of friendly conversations from inquisitive people that I rarely got from my road bike. Even an Aunty of mine was stuck in traffic at an intersection I was waiting in median strip to cross and spotted me saying hi, looking good =D

[joepah]

[quote="deepfraught"]joepah do you have any of the old motors/controllers that were replaced? I'm looking for one to have in hand to compare against the Australian 15mph limited version I have here, in case it's a jumper position on the board. Failing that, a working USA one in hand would mean plan B swap while I have the motor open.
I upped my front sprocket from 42 to 48, and am now pedalling 22mph cruise with motor not doing as much (speed told to me by two road bikes drafting me on two separate occassions who wanted to know more about the bike

I've loved it so much now I've commuted on it for 8 days in favour of my custom parts bin special flatbar road bike that I preferred over all others for fast convenient commuting.


Sorry, but all the replacements were made under warranty so my local distributor took the failed motors with him. With the new soft start and high t/c temps, the motor seems more reliable... Have 5000 miles on it now and it doesn't cut out on high temp any more. I would like to figure out how to remove the 20 mph limit on my bike!

[wymjymn]

Hi, while waiting for for Gaston to show me the way to better performance with the metro, I have a question.
My freewheel has started to make really bad sounds,
is the cshg30 (Shimano 7-Speed Cassette with 11-28 Teeth) an appropriate replacement?
if not, which one should I get?


btw....the 54t front crank I have on mine still seems to need a bit higher gearing for me.....on the level I'm spinning at 22mph...and would actually like to feel as if I'm doing something other than moving my legs around.

thanks


wj

[Ypedal]

the A2B ( like 99% of hub motors ) use freewheel.. not cassette.. smallest you can get on the rear is 16t ( I think the mega-range may go down to 14t... but those are getting rare )

--

small update, this week i dusted off the Metro, charged the on-board pack, removed the 3v booster pack and added a 6v booster in series with the A battery.. so i'm at 48v hot off the charger, cruising at 44v until 4ah where it dips to 42v..

so i'm going aprox 40 kph on the flats, slowing down to 35 kph near the mid-discharge area.. .. not great.. but better than stock !

[wymjymn]

the + 6V sounds like something I will do, thanks.

as to the rear, I counted the small cog....=11teeth
large = 28 teeth

is yours different?


wj

[Ypedal]

I had to replace mine back some time ago, i'm currently using a shimano and my smallest rear is 16t, you are correct tho , the original one had a smaller gear ... will have to dig it up and double check..

[joepah]

That's an interesting thought Y... Adding a 6v in series with the A battery sounds like a good idea.

I went to a 46t chainwheel, but it didn't help much.. I can get to 21 mph with pedaling.

[Ypedal]

Gotten quite a few emails about this so here are a few pictures ..

Using 10ah PSI cells, ( lifepo4 )

a2b-6v-2.JPG (43.99 KiB) Viewed 851 times

Wrapped in crazy-carpet ( thick flexible plastic ), 2 cells in series .. 3.2v each = 6.4v ~ 6.0v operating voltage at this discharge rate..

a2b-6v-1.JPG (51.39 KiB) Viewed 851 times

I charge the 2 cells seperately.. with single cell voltphreaks chargers and anderson connectors, the stock charge plug in the frame for the A pack works the same as usual for the internal 36v pack.

Normally, the A battery fully charges to 41.8v, drops to 38v under load almost right away and fades away to 35v at the end of a long ride..

With the extra 6v, it shows 48.x volts hot off the charger, drops to 45~44v giving aprox 38~40 kph.. and 42v at the end of a ride still going 32 kph.

I need a larger chainring to help with pedaling at top speed, with the shimano 16t rear i'm unable to pedal on level ground, spinning too fast.

This is on an older version of the bike, recent models may be different, but the power wires going into the motor at the swingarm connector, are past the BMS and throttle LED's.. the throttle led's are connected to the BMS of the A pack so are not affected by the extra voltage.

[matt20]

What is the highest voltage that this will take without something catching on fire? I have a 48 volt pack I'd like to connect up, if it could take it...

[Ypedal]

A while back ( not sure what page .. ) .. i ran 16 cell PSI for 53v hot off the charger and dropping to 50v operating voltage for about 10 minutes, nothing went bang...

The soft start controller made 48v sluggish off the line for a longer period it seemed but this is something i have to test again with the CA calibrated to report back accurately.

[Gregor]

Going with a bigger chain-ring might be easier to install, but don't forget you may need to add a few links to your chain. If the rear wheel is easy to remove, then changing from a freewheel that is 16T smallest to 12 or 13 tooth would give you about 4mph more "pedalling added" assist. There are quite a few of these available on ebay, just make sure that you get a 6 speed (I think that is what was stock, tho I'm not sure) and that it has English threads. A shimano brand is probably the easiest to find a freewheel remover for, But again, that tool may have to be modified with a bigger center hole so that the axle will fit through it--I've had to grind the center out of one with a Dremel and it takes quite a while.

[deepfraught]

I didn't change the standard chain because in standard form I was only using 1 (top) and 2 gears on my commute. Now from 42 stock to 48 on the front I'm also using 3rd, leaving the massive 4 gears of larger rear sprockets still unused.

I have found my Australian 200W claimed restricted controller is speed limited to 25kph with throttle only, but does still assist while pedalling up to near zero assistance by 35kph. I don't think taller gearing will help me go higher in speed without adding more voltage like Ypedal has shown. since the standard assist at 35kph is negligible.

I've been riding it for a couple months or more now with the gearing increase mandatory for happy commuting. It is a good speed and is real cycling effort, working (e-relatively) hard to the benchmark of fast road bike commuters who do that pace. Over 35kph would be passing them into the fewer riders who do 35-40kph solo, or pairs/groups drafting each other, and would risk just being drafted by them unless able to break away for a burst with 40kph and taller gearing.

[Gregor]

Ah yes, it is a 7speed stock. A lot of it has to do with the maximum cadence that you are comfortable with--for some it is 50 rpm and for others it's 80 rpm. The higher revs are supposed to be easier on your knees.

[matt20]

A while back ( not sure what page .. ) .. i ran 16 cell PSI for 53v hot off the charger and dropping to 50v operating voltage for about 10 minutes, nothing went bang...

The soft start controller made 48v sluggish off the line for a longer period it seemed but this is something i have to test again with the CA calibrated to report back accurately.

Thanks for the reply. I put a 48 volt ping pack on the back and ran the bike for about 10 miles today. It seems to be working very well. Top speed seems faster than before. All I did was cut the black wire that goes to the auxiliary pack and connected up the +/- with Anderson connectors. The third wire I left disconnected.