Who's got a Current?

[mojoe]

Thanks for the update. That's a bummer about the cable routing. I just measured the space on my bike and it is 5 mm or less. Is that a disconnect plug that you show in the picture? It looks like without the plug, the cable might fit into that tiny space next to the down tube.

You're correct about the video, I watched it, too. They must have changed something since then. They should change it back, to allow more room for the wiring and plug. I've noticed that some of the videos are obviously older than others, as you can see differences in the bikes.

Good to know that the battery can be easily disassembled. The main battery doesn't look too difficult, either. It will be a long time, but it's nice to know that the packs are easily rebuilt when the time comes.

Actually, if the extender battery comes apart that easily, it may not be too much trouble to disconnect the wiring at that end, so that it can be routed through the hole, as it should be. Even with the plastic loom over the wiring, I'd want to put some additional heatshrink or something at that point, for wear. Maybe the best thing to do is drill or grind a larger hole, and use a beefy rubber grommet to prevent abrasion. My bike is black, so it wouldn't be as noticeable as on your white one.

If I get my 3D printer repaired, I may take a stab at making a cover for the exposed terminals when the battery is removed. I'm having trouble finding the correct size sleeve bearing for the 3D printer. In the mean time, perhaps a block of dense foam could be cut to fit there (not Styrofoam).

 

[mojoe]

If anyone is thinking about getting the extender battery, they are offering a $100 discount until 06 March. The discount code is on the web page. I just placed my order.

 

[Mathew Nelson]

Sorry but I don't think it's a good idea.
They should have used a dual battery converter to make it more efficient and get more miles, instead of switching the battery after its depleted.

Sorry but I’m not familiar enough to know what the difference would be. Guessing that the level indicator would show both batteries and draw from both simultaneously? Can you explain?

Also, I want my retroactive $100 discount!

 

[Mathew Nelson]

If anyone is thinking about getting the extender battery, they are offering a $100 discount until 06 March. The discount code is on the web page. I just placed my order.

FYI I contacted them and they refunded me $100 from my order that I recieved this week

 

[Mathew Nelson]

I doubt it's drawing simultaneously, if it did, the voltage will stay the same.

Also, what kind of connector do you have?

You can get a 48V 14Ah (672Wh) battery here.

EUNORAU 36V13Ah/17Ah 48V14Ah 1203 Rear Rack Ebike Battery(Rack include

All batteries from EUNORAU come with original SAN YO, LG, and SAMSUNG cells. Customers can get after-sale services from a local EUNORAU service agent. This battery ship with rack. Normal Voltage: 36V13AH 36V17AH 48V14AH Cell Brand: Samsung Samsung or Sanyo Samsung 35E Cell Code: 18650 18650...

eunorau-ebike.com

The connector is the one show in the install video, here is a screen shot. I’m not an expert on these connectors but I haven’t seen one like it before. Can you explain your comments, “they should have used a dual battery converter to make it more efficient and get more miles”.

 

[mojoe]

I just watched that YT video. Sorry, but without more details about what is in that magic device, and some independent data, my opinion is that it is just snake oil. Feel free to disagree, and to spend your money on it if you wish. I'm not inclined to believe some random YT guy just because he believes that device works for him. I am quite versed in electronics and battery chemistries, so I'd need more proof.

His explanation about the different current draw rates from multiple batteries allowing you to get more capacity is bogus. That is not how lithium batteries work. If he were talking about lead acid batteries, then yes, the rate of discharge does matter. Lithium batteries can be discharged at widely different currents, and will still give the same overall rated capacity. The only way that a high discharge rate would matter, is if it was substantially over the maximum rated discharge rate for that battery. This is not going to happen with a properly designed ebike.

Also, using the battery bars as a measure of remaining capacity is not a very accurate method. I'm sure that most of us have experienced this issue. You need a calibrated DC electronic load to accurately measure battery capacity. I have two different types, so I am able to make this type of measurement, and have with batteries for other devices.

I also question how he is using batteries with different voltages with that device. If he was using a 36V and a 48V battery with a 36V motor, then a buck converter circuit for the 48V battery would allow that. If the motor was 48V, then a boost converter for the 36V battery would be needed. However, buck or boost converters are less than 100% efficient, so you will have losses. I doubt that either a buck or boost converter is used in the device he talks about, as the device is too small for the needed power handling capacity.

I don't dispute that the device allows him to hook up batteries in parallel without causing issues with voltage balancing., as that could be accomplished with some diodes, or similar semiconductor devices. I just don't believe the rest of his statements. There is no electronic circuit in existence that does not have power loss, even if that loss may be small. Any claim to the contrary is BS, and is as believable as perpetual energy It would be quite interesting to see what is inside one of those devices.

Edit: I just noticed that his web site sells that device, so I also question his objectivity.

I don't wish to get into an argument about this topic, so like I said, if you disagree, go ahead and spend your money. I've had my say, and tried to lay out some facts. Believe what you like.

Also, thanks for pointing out that other battery and rack combination. At first glance, it does look like a better deal. However, once you add in the necessary circuitry and plugs, it looks less attractive (not even counting your time). I agree that $800 is quite a lot for the Priority extender battery. With the $100 discount, I think you're very close to the price of the DIY solution. Plus, the Priority version has a warranty. I just spent my money on the Priority battery.

 

[mojoe]

Within the rated discharge rates of the cells used, you will get the same capacity. Now, if you used an extremely low discharge rate, you might be at or below the self-discharge rate, which would affect results. Similarly, if you used an extremely high discharge rate, you might be exceeding the physical limits of what that cell design is capable of. A good example of this is the recent development by Tesla of a new way to manufacture the cells that they use to allow higher discharge and charge rates than previously possible.

Like I said, this doesn't apply to lead acid, and some other chemistries. Lead acid batteries are rated at a 20 hour discharge rate. If you draw more current than that, you will get less capacity. Even using the 20 hour rate, you shouldn't routinely discharge a lead acid battery below 50%, as that will damage the cells, further reducing the capacity.

Lithium chemistries have their own set of issues, but in general, you can use almost 100% of the watt hour capacity of a lithium cell. You do need a BMS to prevent over charge or discharge, which will damage lithium cells. Using bare lithium cells to make a battery, without a BMS is just asking for a fire.

I did some Googling on battery combiners. It does look like they all use high wattage diodes to do the job. The recent version of the DATEx device may have added a voltage comparator to allow mixed voltages. The description says that they "burn" the extra voltage, which means that they waste it in a load resistor, as heat, until the higher voltage pack meets the lower voltage pack. Certainly not worth the $150 price, and reinforces my assertion that the statements made in that YT video are pure BS.

Just a quick calculation using the nominal voltages, not the maximum when charged, and assuming no circuit losses: if you have one 48V battery and one 36V battery hooked up to the combiner, that means that you'd need to drop the difference of 12V. If you were drawing 30A (the maximum that the device is rated for), that means that you are dissipating 360W. Just imagine having a 360W heater attached to your ebike. Just wasted energy.

If you had two batteries of the same voltage, you'd still have some circuit losses, and the device would still get quite warm. Again, wasted energy. There is no magic solution to get around the physics.

 

[mojoe]

Looks like the battery capacity will suffer under high discharge rate.

"The Li-ion Energy Cell is made for maximum capacity to provide long runtimes. The Panasonic NCR18650B Energy Cell (Figure 1) has high capacity but is less enduring when discharged at 2C. At the discharge cutoff of 3.0V/cell, the 2C discharge produces only about 2.3Ah rather than the specified 3.2Ah."

https://batteryuniversity.com/img/content/18650chargeDischarge-web.jpg

Source:

BU-501a: Discharge Characteristics of Li-ion

BU meta description needed...

batteryuniversity.com

Yes, like I said, it depends on what the cells used were designed for. Some are designed for low discharge rates, some for high discharge rates. Within the specified limits, you will get essentially the same capacity.

 

[Amishman]

My Current has had from October 2020, when I got it, a troublesome lock plate. I could not easily get the battery out. In December 2021, I asked them to fix The battery when I sent them a video of the half hour of jimmying it took to get the bike plate out. Somehow, the LBS adjusted the plate and it came out easily, too easily. When I went over a sewer grate down a hill at about 25mph, the battery popped out and went careening into the road. Fortunately, there was no car to smash it over and no hazmat incident. I called up Priority and they agreed this was a warranty issue and had me take it into the local bike shop. The extra battery I purchased was pretty smashed up, so in addition to the lock plate, I am getting one of those range extenders. Aside from getting the battery in and out and a lesser quibble of no throttle and the smaller battery capacity, the bike is really nice, buttery to pedal, and enjoyable. I did upgrade and get Schwalbe puncture resistant tires…I would still recommend it.l

 

[BobR]

I just got my Priority Current! Shimano 5-speed, with Costco discount. I live in a hilly area, so I’m trying it out on some inclines, and pleased with how it powers up them. It is bigger and heavier than my old (pedal only) 3-speed I’ve had for years, so I’m doing short and simple trips to get used to the difference.
When I was shopping around, another brand with this internal hub gearing was described by the LBS staff as being able to shift up to higher gears without letting off pedaling. I tried that today and was quite surprised it does that without complaint. I still have to pause when shifting to a lower gear.
Thanks for this thread.

- Bob R (new member)

 

[mojoe]

My extender battery arrived today. I didn't like how close the wires would be to the rear tire, so I drilled a hole. I am disappointed that I had to do this, as according to their video, it was possible to route the cables to the front of that metal plate at one point.

If you go this route, there are two things to be very careful of: If you drill too far back, you will destroy part of the bike serial number; The wiring for the rear light runs underneath, so don't chop it up.

It would be best to drill two 1/4 inch holes, side by side, close to the front edge of the metal plate. Then use a file or Dremel to make a single oval, and smooth the edges. The plastic wire loom should protect against chaffing, but I'm going to add a grommet for extra protection. I put a thin piece of metal to the front while drilling and filing, so if I slipped, I wouldn't damage the paint on the rear of the seat post tube.

It was difficult to see where the plug inserts, so I laid the bike on its side, to make things easier.

The extender battery is charging. Now I need to plan a very long ride

 

[mojoe]

I just got my Priority Current! Shimano 5-speed, with Costco discount. I live in a hilly area, so I’m trying it out on some inclines, and pleased with how it powers up them. It is bigger and heavier than my old (pedal only) 3-speed I’ve had for years, so I’m doing short and simple trips to get used to the difference.
When I was shopping around, another brand with this internal hub gearing was described by the LBS staff as being able to shift up to higher gears without letting off pedaling. I tried that today and was quite surprised it does that without complaint. I still have to pause when shifting to a lower gear.
Thanks for this thread.

- Bob R (new member)

Congratulations on the new ebike. The more I ride mine, the more I love it.

The only full size ebikes that come close in weight to a regular bike are the Specialized SL series. They are very nice, but don't have the range or power compared to other ebikes, even others from Specialized. If you were doing rides that weren't overly long, without significant hills, and had to have light weight, the SL series would be a good choice, but more costly. Some of the small folding ebikes come close in weight. My Gocycle GX weighs 38 pounds. Compared to the vast majority of ebikes that I am aware of, the Current and some Gazelle models are among the lightest (I don't count any of the single speed ebikes, as I'd want a multi-speed shifter). Motors, batteries and beefier frames add up. If you had money to burn, you could get an all carbon composite ebike

With the Current, a number of times I have started off, only to realize that I forgot to turn on the pedal assist. On flat terrain, it wouldn't be too hard to pedal the Current for a while. At some point, I'll have to see just how far I can do this, with no assist - a simulated dead battery.

The weather was good today (sunny and 50-ish), so I took the Current for a ride on some dirt multi-use trails for the first time. I've ridden these trails a number of times with my Gocycle (after putting on more suitable tires). The Gocycle handled the trails well, except for an area with deep and loose sand. With the stock Goodyear tires on the Current, I was able to power through the sand by bumping up the assist a bit. The larger diameter tires on the Current probably helped, also.

I've ridden some hills that weren't extremely steep, but had very long grades. I just bump up the assist and keep on pedaling. I try to keep it on level 1 most of the time, so that I get a good workout. With the new second battery, I doubt I'll be able to ride long enough to deplete both batteries.

 

[BobR]

Congratulations on the new ebike. The more I ride mine, the more I love it.

The only full size ebikes that come close in weight to a regular bike are the Specialized SL series. They are very nice, but don't have the range or power compared to other ebikes

Thanks mojoe,
I did test ride (twice) the Specialized Como SL (4.0). Same 5-speed. I liked it very much. I have no idea if it would have had the range I needed for my (eventual) commute, but the LBS staff assured me it would handle the hilly route and distance (they thought I could make close to two round trips between charges on the Como SL). I liked the handlebars and seating position better on the Como SL than my Current, but I can talk to my LBS about new handlebars on my Current (or I can try to get used to the posture).

The weight of the Priority Current does not bother me. I too pedal away from home starting with power assist set to “0”, then turn it up later. I deliberately ran the battery down to one bar flashing, and it seems the bike goes into half-output mode of some type at that point. I still got home with that lower level of assist, but my last 5% incline was slow as I kept shifting down (eventually all the way to first gear on the last bit up). When I went back out to the garage to get the battery to charge indoors*, it had bounced back to a solid one bar after the brief rest, so maybe I could have drained it further but I couldn’t fit in another ride.
*(I could not have done that if I had chosen the Como SL, with it’s built-in battery).

Have fun going long distances now that you have the extender battery!

 

[Doggyman1202]

I liked the handlebars and seating position better on the Como SL than my Current, but I can talk to my LBS about new handlebars on my Current (or I can try to get used to the posture).

I fiddled around with both the handlebar position and seat angle early on, and was able to dial-in a really comfortable riding position. I would suggest you experiment first before investing in new handlebars.

 

[mojoe]

I too experimented with seat and handlebar position. I now have the seat forward a bit, and the handlebars tilted up about 60 degrees. Now I don't slide off the seat, and my hands don't get numb. If you rotate the handle bars very far, you'll also have to reposition all the controls. Just loosen the bolts and rotate everything.

Look on YT for videos about how to fit a bike to you. There is more to it than you think.

 

[Mathew Nelson]

Took a bit of a spill on my Current this past weekend. The left brake lever bent. Taking it apart to sort it out, it turns out that you can adjust the lever distance! There is a small threaded cylinder with a hex key end that you turn.

The take apart was simple enough. The 3 Torx head screws holding the master cylinder cover on, slide out the pivot pin of the lever, then turn the threaded cylinder with a hex key until it disengages from the threaded cylinder in the lever.

I put the lever in a vice with soft jaws and mostly reformed it. Then a wire brush wheel on my bench grinder and black rattle can paint. Not perfect but I can ride again.

 

[Mathew Nelson]

I forgot to post this ride I did a few weeks ago to break in my extended battery. I wanted to see what it could do so I left the PA on the entire time, mostly level 1 but I did dial it up to 5 in some spots. The limiting factor was really my butt as I was in the saddle for many hours. I rode a solid 70 miles, with hills, flats... as I pulled into my garage I had 3 bars of the rear battery left.

 

[BobR]

Enjoying my Priority Current this past month of ownership. I’ve commuted to work on a few nice days so far, and pleasure rides or errands. I have a question about battery chargers.

My commute is about 24 miles round trip in a hilly region. The max incline isn’t too bad (I measured 8% on one, but the apps say the hills are 5% overall) but some are long. I’ve not developed leg strength yet, and I’m trying not to stress my heart, so I’m using power assist as much as I like. The battery has enough juice to get to work and back with at least one bar left, but if I’ve been using power assist above 20mph and trying to rush my commute I end up losing level 5 before I get home. Still, I get up all the hills in 5th gear at level 4 or 5, except the final 8% grade where I downshift too.

I brought the charger in my backpack to give a lunch-hour boost one day. I don’t like having to use the space/weight. So, I’m thinking of getting an extra charger to have at the office. That way I can still rush on high power and not be afraid I will lose the extra oomph in the last couple miles home.

If I keep up my riding, I figure my legs will get stronger and I’ll be less reliant on the power assist. Also, I’m hoping the rail-trail gets developed soon, which will take me off the 55mph road and avoid the hills. But for now, I’m using most of the power capacity.

Should I look into special chargers, or just get the Priority brand? Which would baby the battery best?

 

[Doggyman1202]

Enjoying my Priority Current this past month of ownership. I’ve commuted to work on a few nice days so far, and pleasure rides or errands. I have a question about battery chargers.

My commute is about 24 miles round trip in a hilly region. The max incline isn’t too bad (I measured 8% on one, but the apps say the hills are 5% overall) but some are long. I’ve not developed leg strength yet, and I’m trying not to stress my heart, so I’m using power assist as much as I like. The battery has enough juice to get to work and back with at least one bar left, but if I’ve been using power assist above 20mph and trying to rush my commute I end up losing level 5 before I get home. Still, I get up all the hills in 5th gear at level 4 or 5, except the final 8% grade where I downshift too.

I brought the charger in my backpack to give a lunch-hour boost one day. I don’t like having to use the space/weight. So, I’m thinking of getting an extra charger to have at the office. That way I can still rush on high power and not be afraid I will lose the extra oomph in the last couple miles home.

If I keep up my riding, I figure my legs will get stronger and I’ll be less reliant on the power assist. Also, I’m hoping the rail-trail gets developed soon, which will take me off the 55mph road and avoid the hills. But for now, I’m using most of the power capacity.

Should I look into special chargers, or just get the Priority brand? Which would baby the battery best?

Inasmuch as you could buy an aftermarket charger for less than half the price, I'd still buy the charger Priority stands behind. Relative to the approximate $3k original investment, another $80 isn't much.

Also, based on your riding experience and commuting requirements, a 2nd charger sounds like a great convenience and a perfect way to alleviate your understandable range anxiety. Also, one less thing to lug in your backpack. In short...Go for it!

 

[ebikerr]

Just got my current from Costco for 2599$. Its a shimano 5 speed. I was under the impression it was enviolo. But I am okay, I am guessing lower gears will be lower on envilo, while highest gear on shimanu will get me similar cadence? I could not find specs anywhere, i..e the cadence at higher speeds eg 25mph in highest gear at 5 assist.
Also wondering what tire pressures to run for my commute (90% paved, 10% gravel, about 10 miles)

Secondly, in the future, is it possible to upgrade to a 9 speed shimano hub(internal) from the current 5 speed


Also wondering about tire pressures on goodyear tires. I don't see it listed anywhere on sidewall (or maybe its too hard to read!)