2011 Currie iZip Ultra Review

Canonical link here: http://syonyk.blogspot.com/2015/06/2011-izip-ultra-review.html

This is a bike I rebuilt the battery pack on:
http://syonyk.blogspot.com/2015/05/izip-ultra-2011-battery-pack-teardown-1.html
http://syonyk.blogspot.com/2015/05/izip-ultra-2011-battery-pack-rebuild-2.html
http://syonyk.blogspot.com/2015/05/izip-ultra-pack-rebuild-33.html

2011 Currie iZip Ultra Review







This new-to-me bike came stone dead (as far as the "electric" part of it was concerned). It now lives with a freshly rebuilt battery pack! So, that raises the question: How is it to ride?

There were a few issues for early owners of these bikes - broken spokes in the rear were a common complaint. However, this isn't a problem on mine, because the previous owner replaced all the rear spokes. He also replaced the cables to deal with some snagging issues, and I don't think it has slime in the tubes right now (apparently it solidifies if the wheels don't move for long enough).

I've been using this for potting around locally since I finished rebuilding the pack (for those not familiar, I rebuilt the 10AH stock pack as a ~14AH pack), and I think I've got a slight feel for the character and nature of the bike now.

Which is: This is really a cruiser style bike with road tires that happens to love climbing hills.


Ergonomics
The bike is a pretty standard, tall bike. I've ridden many like it over the years, so it feels reasonable. The seat is very wide and I personally find it rather uncomfortable for longer rides, though my daily driver has a very narrow seat on it. It's something I should consider changing out, but probably won't.

The riding position is very tall. This is great for seeing and being seen!

Overall, it's fairly comfortable to ride. It's similar to any other tall commuter style hybrid bike.

Riding & Power Delivery
This bike comes with a 500W motor. It's a CURRIE ELETRO DRIVE(R) if you care.





Initially, I wasn't terribly happy with the power. I was expecting something similar to my commuter bike, and it's very much not. This bike abides by the federal US limit of 20mph under motor assist, and the motor won't help you beyond that. It won't help you much close to that either.

However, if you slow down and ride the bike where it wants to be ridden, around 15mph, it's quite nice, and the motor does a great job of helping you along when you need it. It will happily let you do all the work on a flat road or a slight downgrade, depending on the power setting.

The incredible part, though, is hill climbing at low speeds. This thing climbs hills incredibly well, and in low gears will claw straight up very steep, challenging trails that it's almost impossible to ride up with similar tires (without a motor). The motor smooths out the power delivery and it just claws up the gravel and dirt like a mountain goat. It's not an offroad bike, but it'll sure fake it!

I think most of the behavior comes down to the sensor system being a torque sensing system, combined with a desire to be smooth and meet federal regulations. Climbing hills is a low speed, high torque activity, and the motor is pretty much running wide open. High speed running is lower torque (combined with the limits in motor output at higher speed), so it won't assist as much. Assisting fully up to 20mph and then cutting entirely would be a poor riding experience, so it feels like there's a taper in power delivery above about 17mph.

Once you learn what to expect, it's really quite nice!

One glitch I've found is that walking the bike on a rough surface will sometimes engage the motor if the rear wheel bounces. So be careful walking it over railroad tracks or such (if they're not a level crossing).

Another issue I've noticed occurs at low speeds and tight corners (such as climbing a set of switchback ramps for a pedestrian/bike overpass). The motor won't run until the bike is moving, but if you're moving slowly and turning tightly, the motor will occasionally add power at very much the wrong time, and can make things a bit exciting (especially if it's slick out and the front wheel is turned sharply). Fortunately, the brake lever cutoffs fix this - just depress a brake lever slightly when you don't want the motor to come on, and it won't.

It's unwise to run the bike without the brake cutoffs in place. If you stop pedaling, the motor continues to provide power for a few seconds. I tried it for a bit with the cutoffs removed (as that's how it was when I got it), and... no. Don't. It's not safe to ride like that.



Another slightly unusual feature of this bike is the front shock. It's a single shock, above where the forks split (there's a bit of a fork gaiter over it). I'm not sure exactly how it works, but it works just fine - it absorbs moderate bumps just fine. It's not a long stroke, but it's enough.

As to the range on the rebuilt battery pack: I don't know! I haven't come anywhere near running the battery flat, even with 10 mile round trips. Sometime I'll go run it flat, but it's going to take me a lot of miles. It's more than long enough to not worry about it.

Controls







The brakes are cable operated disc brakes, and are more than up to the task of stopping the bike. There's occasionally some noise or feedback in the levers, but as long as you've got the brakes adjusted properly (which does have to happen somewhat regularly), they do a wonderful job of bringing the bike down from speed in a hurry. Remember that the stock brakes have brake cutoff sensors in them, so pressing either brake lever will cut the motor instantly (and you can't easily replace the brake levers unless they have similar functionality).

The shifters are in the "traditional" position (front chainring on the left, rear sprockets on the right), and work fine - they're reasoanbly cheap index shifters, but they get the job done. Since this is a pedal assist bike, there's no throttle to operate, so this works perfectly. You really don't need anything but the largest front chainring most of the time, though. I only use the smallest chainring for climbing hills I really have no business climbing on this bike.



The power control console is very simple. There's an on/off switch (hold to turn off), and a set of buttons to adjust the power delivery. Yes, it's upside down - this keeps it below the bars, where it's a tiny bit less obvious to people if you are on trails that maybe sort of shouldn't have electric bikes on them. In theory, of course.

Charger







The charger is quite nice. It uses a 4 pin XLR cable as the interface to the bike, and the bike-side connector is well protected from the elements by a cover. The charger also has a switch on the back, so you can plug the bike in and then turn the charger on. The fan is audible while charging, but nothing absurd.

For those who care, the charger is rated 42VDC/4A.

Based on the history of my bike and why the pack is dead, I do suspect that if there's a power outage, the charger can get into a state where it drains the battery instead of charging it. So, if there's a power glitch, cycle the charger afterwards. Or, just charge the bike and then take it off the charger, though this obviously means you can't ignore the bike for another few years and expect it to work.

The Kickstand



The kickstand is attached to the rear dropouts instead of the center of the frame. It's a really nice location for a kickstand, because it doesn't interfere with the pedal rotation! You can back the bike up with the kickstand down and not hit the pedals! Though it does require remembering to bring it up, as it won't get knocked up by pedal rotation.

Complaints
It has no lights! If you actually care about people riding electric bikes, put some lights on the thing. Or at least run some power so people can install lights. You have a huge battery pack - a front and rear LED makes a huge difference in being seen, and is quite nice for seeing as well. Yes, a sticker saying "Do not ride at night!" is cheaper. I don't care. Put lights on your ebike.



I'm not sure if it's the stock seat or not, but the seat is very wide. This is probably a personal preference, but I'd prefer a narrower, harder seat that didn't bulge up in front and press on sensitive male parts. It's the type of seat that's comfortable for a few miles, and miserable after a few dozen miles.

Overall
I quite like this bike, though I feel it's a little bit misleading. The frame and tires suggest it's a fairly high speed road bike, and it just isn't. It's a very efficient 15mph cruiser that can chew up hills impressively.

It's a fairly comfortable ride, and the motor assist is nice. It's a surprisingly capable bike in hilly areas, and it's certainly well suited to "that one hill" - or "those several hills." Just don't ask it to run particularly fast, and you're fine!

If you can find a used one in good shape, it's definitely a solid bike, and with the addition of some lights and perhaps a different seat, would be an excellent year round bike. It'll even fit snow tires!


As a side note, the difference in the grass color between early May when I posted about my commuter bike and these photos is significant!


Do you have one? How do you like it?

Syonyk said:

This bike comes with a 500W motor. It's a CURRIE ELETRO DRIVE(R) if you care.

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Appears to be a Bafang BPM motor? Not sure which "code" (winding version), possibly 11. IIUC, the labelling indicates it was originally a 700c wheel.

Another slightly unusual feature of this bike is the front shock. It's a single shock, above where the forks split (there's a bit of a fork gaiter over it). I'm not sure exactly how it works, but it works just fine - it absorbs moderate bumps just fine. It's not a long stroke, but it's enough.

Click to expand...

Most likely, it's basically just a spring between the bottom headset bearing race position (though actually pressing on a separate part of the steerer tube itself, the outer one, with an inner one sliding inside that like a fork leg) and the top of the fork crown's steerer tube mount, more or less. I haven't had one to take apart, so don't know the exact details, just seen one without the accordion cover (rotted away, probably), on a random bike at a lockup. It may have a damper inside too, dunno. Seemed to work more or less like a seatpost shock. Dunno if it had any adjustments; I didn't want to mess with a bike that wasn't mine.

It has no lights! If you actually care about people riding electric bikes, put some lights on the thing. Or at least run some power so people can install lights. You have a huge battery pack - a front and rear LED makes a huge difference in being seen, and is quite nice for seeing as well. Yes, a sticker saying "Do not ride at night!" is cheaper. I don't care. Put lights on your ebike.

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I heartily agree with you on that one.

amberwolf said:

Appears to be a Bafang BPM motor? Not sure which "code" (winding version), possibly 11. IIUC, the labelling indicates it was originally a 700c wheel.

Click to expand...

I think it's still a 700C wheel, or something very close. I haven't actually checked.

Most likely, it's basically just a spring between the bottom headset bearing race position (though actually pressing on a separate part of the steerer tube itself, the outer one, with an inner one sliding inside that like a fork leg) and the top of the fork crown's steerer tube mount, more or less. I haven't had one to take apart, so don't know the exact details, just seen one without the accordion cover (rotted away, probably), on a random bike at a lockup. It may have a damper inside too, dunno. Seemed to work more or less like a seatpost shock. Dunno if it had any adjustments; I didn't want to mess with a bike that wasn't mine.

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It's probably something simple. There are no adjustments I can find, but it works decently enough. I'd obviously prefer something nicer, but on a $2000-ish bike, it's better than nothing.

I heartily agree with you on that one.

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Yeah. It sadens me how many of the new crowdfunded bikes don't have lights. If you don't have lights and fenders, you've built a toy, not a tool. IMO.

Syonyk said:

I think it's still a 700C wheel, or something very close. I haven't actually checked.

Click to expand...

FWIW, if you had smaller wheels, it would climb even better, though probably have a slower top speed.

It's probably something simple. There are no adjustments I can find, but it works decently enough. I'd obviously prefer something nicer, but on a $2000-ish bike, it's better than nothing

Click to expand...

On many roads (those with enough less fast/aggressie traffic to be safe for non-car/truck vehicles) around here, without any suspension you'd better ride carefully and in broad daylight. Even a car headlight like mine at night isn't sufficient to show you all the crash-you-break-your-wheels holes and cracks; some just don't look like what they are until too late, because patches in teh pavement look exactly the same....and there are places where if you avoid everything you *think* is a problem, you run into soemthing worse, or else it's just not possible, or you end up having to move out into traffic that is even more dangerous.

(that's all assuming you're going 15-20MPH)

Yeah. It sadens me how many of the new crowdfunded bikes don't have lights. If you don't have lights and fenders, you've built a toy, not a tool. IMO.

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Pretty much (fenders optional here, most of the year, but not lights)--you've seen my bike & trike, right?

Just on the fenders/lights thing... having had to work on a bunch of bikes with integrated lights and fenders, they're usually a giant pain! Either trying to fault trace the wire that broke inside the frame somewhere, or trying to source out a oddball light bulb, or find a replacement for the custom hardware they came up with for the fender, your tool could be stuck in some bike shop waiting on parts for a while. Compare that with the legion of cheap bright lights and scores of decent cheap fenders out there... sometimes over integration of the systems isn't a good thing. The Stromer is like that... it has a double wall aluminum fender that is part of the rack...looks great, but has about two mm clearance, so if the rack slides down the least little bit under load, it rubs the tire like crazy. And just had to put a new bulb in a guys Easy Motion. We had the bulb, but it would have been days out of use if we had to order it, and no other shops in at least a 100 mile radius have one.

That's a fair point about integrating systems. :/ I do get the impression an awful lot of ebike manufacturers are people who haven't had to actually *work* on bicycles.

Nice review.. I have an opportunity to get a "new old stock" (so supposedly good battery) Izip ultra.. and so I'm curious if after a year you still recommend it.
I have a 10% grade for .25 miles on my way to work… so while other reviews questioned its hill climbing you seemed to like it.

I'll absolutely need to add lights.. was there any easy point to tap into the bikes power.. (silly to add another battery for the lights).

Any other quality issues after a year?

DrInnovation said:

Nice review.. I have an opportunity to get a "new old stock" (so supposedly good battery) Izip ultra.. and so I'm curious if after a year you still recommend it.

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If you can get it cheap, it's still a perfectly decent bike. I wouldn't pay more than about $1000 for one, and I'd question the battery capacity remaining if it's sat for a while, but it's decent enough.

"Supposedly good battery" is the catch here. It's not going to be nearly what it was when new, but if it holds a charge and runs, you should get at least 60-70% of rated capacity out of it.

I have a 10% grade for .25 miles on my way to work… so while other reviews questioned its hill climbing you seemed to like it.

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The original owner of mine wasn't happy with the hill climbing, and had problems with it cutting out while climbing. I had no problems after rebuilding the pack, but I also weigh a good bit less than him. I'm around 250lb and I think it climbs hills just fine, if a bit slower than I'd prefer. My wife, who weighs half what I do, absolutely rockets up hills on it - she can climb hills on it nearly as fast as my 1000W commuter build. So, if you're 300+lb, you may have problems, but otherwise, it'll be just fine - and still radically better than no motor. It's a geared hub motor, so it has plenty of torque.

The assist does drop off above 15mph, so don't expect a rocket. But it's just fine on hills and provides plenty of assist at lower speeds. I use it as my "long range" bike, because I can do a 20 mile round trip at level 3 assist (of 5) with half the battery remaining.

I'll absolutely need to add lights.. was there any easy point to tap into the bikes power.. (silly to add another battery for the lights).

Click to expand...

If you drop the bottom of the downtube out, you can access the battery and controller. I'd tap in there - pack voltage should be easy enough to find pre-controller. I haven't done anything with that since it's a daytime only bike for me - my commuter build is radically better lit for night use.

Any other quality issues after a year?

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Make sure your fenders are well secured. Mine ate one. Otherwise, no, but I haven't ridden it that much. I ride it every few weeks if I need something long range, and my wife rides it if we're potting about together. No issues so far, but I really haven't beaten on it much.

Thanks.. great info. The bike is $800.. It is new and if they kept it in a cool place or at 50% charge I would expect the 18650's to be nearly unimpacted. Samsung cells age well if cared for. I've asked about where/how it was stored, so we'll see. They are offering the original warranty.

I'm 200 so should be fine it it works for you. I don't care much about speed, just want reliable transport. I'm riding a old washout that eats plenary gears regularly.
(I am considering moving to a less expensive bike I can build with dual (local used) 800w hubs which I trying to get at a great price. Figure the 800w will climb better, and with 2 hubs will have a hot spare or even more power if I want it. But since I have to build it it may not be as reliable as a new bike.

I was hoping there was power up top.. would have looked nicer. Maybe I'll make it plug into charging port

What fenders? The one they are offering did not have any..

DrInnovation said:

I'm 200 so should be fine it it works for you. I don't care much about speed, just want reliable transport. I'm riding a old washout that eats plenary gears regularly.

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Should be fine, then.

I was hoping there was power up top.. would have looked nicer. Maybe I'll make it plug into charging port

What fenders? The one they are offering did not have any..

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You can probably plug into the charge port - IIRC, it's always live. I just didn't want something hanging out up there and wouldn't put a plug there while riding.

And I guess the fenders on mine were aftermarket then.

The charge port shouldn't get water into the battery pack unless you've taken it swimming.

https://syonyk.blogspot.com/2015/05/izip-ultra-2011-battery-pack-teardown-1.html - I did a teardown of the pack, you can see the "banana" battery. You'd have to stick a hose in the charge port and seal the bottom of the downtube to get water in the battery.