First ride -> newbie questions

[YoSamES]

I bought an e-Moto brand Ridge 4.5 ebike as a clearance/demo unit for $450.
http://emotoev.com/products/bicycles/street/ridge45/index.html

Some specs are different from the website, but it says it has a "variable pedal assist sensor with speed controller". It's not a torque-sensing unit, I'm pretty sure. It also has a twist throttle. There is no console, no way to select different levels of assist. From the description, I assumed the controller did that automagically.
So when riding, what I find that there seems to be only one assisted road speed. Let's say it's 15 MPH or 25 KPH if you prefer. Whatever.

Starting out from a stop, with the key on, but not using the throttle, at maybe 4 MPH it starts assisting. Then, if I only want to go 8 MPH, I have to coast, then pedal, then coast, then pedal, etc. Which in turn causes the assist to switch on, then off, then on, etc. There does not seem to be a way to go a steadily-assisted speed less than top speed (15). So that's one thing I'd like to figure out.

Second and more importantly, at 15 MPH, even in the highest gear (6th), the cadence is faster than I'd like. I would like to pedal at a slower, leisurely cadence and let the battery do most of the work. It has a 6 speed Shimano gearset with a 14t high gear. I didn't count the teeth on the front, but there is definitely room inside the chain guard for a larger front sprocket. At least 2" larger diameter, maybe even more. Since we don't plan to outride our battery range (I know, lol), and we just want to ride assisted with no hills even if we do have to pedal, should I gear it up? As it is, none of the other gears are of any use in an assist situation.

Lastly, the throttle. I expected a variable assist out of it. But as far as I can tell, it's just an on-off switch. Twist the throttle and it goes down the road without pedaling, but again at only a fixed speed.

The controller resides in the metal box built in the frame below the battery. I haven't taken the side of it off to see what's in there. I'm guessing some of my wishes could come true with a better controller? I'll upload some photos of the electric gear in a few minutes, just for anyone who is interested.

I'm sure some of my "issues" are just the nature of the entry level ebike beast. If so, I'm interested in hearing how our (wife's and my) next bikes should be built to make it more to our liking.

 

[YoSamES]

Electric components:

 

[d8veh]

If you follow the wire from the throttle to the compartment under the battery, where it connects to the controller. It'll have 3 wires together (black, red and white or green), two wires for the switch and one for the LEDs. Try and identify the three for the throttle, which are often on their own connector. Measure the voltage between the black and the signal wire (probably white or green). It should change when you open and close the throttle. If it simply switches from low to high, you can solve your power problems with a new throttle, but it looks like a normal variable one in the photo, so I wouldn't hold out too much hope, but are you sure that it doesn't give variable power? Some bikes like that have very small controllers, to fit in that compartment, so changing to a better one isn't easy. You need to measure the exact size of the aluminium case to see if others will fit. Hopefully, there will be room for a KU65 from BMSBattery, which will give you everything you want.

To get a more comfortable pedal speed, yo must change either the back gears to a DNP free-wheel set with 11T top gear, which requires a special tool for ebikes to remove the old one that you should be able to buy at the same place as the free-wheel; or you have to change the front chainwheel to a 48T or52T, but you'll have to chuck the nice chainguard, and you might have a problem with the pedal sensor if it's not the magnet disk type. A photo of it would help. If you have the normal pedal sensor, a good solution is to fit a 52T/39T double chain-wheel off a road bike because they're very easy to find. You don't need a front derailleur. If you come to a big hill so you want to use the 39T one, you just hook the chain across with a twig, and then hook it back to the 52T one when you get to the top.

 

[YoSamES]

Thanks! I'll check when I can on the points you raised, and post the info here.

 

[dogman dan]

First thing I'd do, is just unplug the pedelec, and see if it runs on just the throttle. Then you should be able to hold a low setting, and ride with minimal assist at 5 mph. If not, then start learning what to do to replace it all with a normal throttle.

Second thing would be to look for a bigger front crank gear. Regular mtb's generally come in 44 and 48t. 48t is good IMO, for street riding. Likely to still fit, if not definitely you can modify the chain guard mount to clear that.

 

[YoSamES]

I have a bunch of snow to clear today. Some time after that I'll open up the controller box on the frame and shoot some pics so you guys can point me in the right direction.

 

[YoSamES]

OK, here are some photos. Please tell me what I've got, and what specifics apply to the advice above. I've included shots of the motor and battery just to complete the picture.

Battery:

Motor, 24/250. I haven't looked up the UPC code yet, but if anyone recognizes the motor, please let me know. Doesn't matter much I suppose. I'm guessing it is a geared brushless motor with hall sensors.

Controller (98x67x35mm not including wires) in its nest:

Controller label:

Wires going to throttle and SOC led display: R, G, Blu, with a yellow connected to the Batt + cable.
One set is R, G, Bk: goes to the hall sensors on the crank.

Wires going to motor. Larger gauge: Blu, G, Y; Smaller gauge: R, G, Blu, Bk, Y. I know enough to know that the first 3 involve juice and the smaller ones involve control, sensors, whatever.

Hall sensors at crank:

Further advice welcomed.

PS: I omitted shots of the R-Blu pairs coming from brakes.

 

[YoSamES]

Found the source of my bike. This is it exactly, less any e-Moto decals:
http://www.hongduvehicle.com/1-city-bike-2.html

edit: mine is 24v, otherwise the same unit.

 

[docnjoj]

Found the source of my bike. This is it exactly, less any e-Moto decals:
http://www.hongduvehicle.com/1-city-bike-2.html

Well almost. You have a 24 volt nominal battery and a 24 volt controller. The ones that you showed in the picture say 36 volts.
otherDoc

 

[YoSamES]

Found the source of my bike. This is it exactly, less any e-Moto decals:
http://www.hongduvehicle.com/1-city-bike-2.html

Well almost. You have a 24 volt nominal battery and a 24 volt controller. The ones that you showed in the picture say 36 volts.
otherDoc

Yes, you're right. I noticed it but forgot about that.

 

[YoSamES]

OK, tested the throttle voltages, and I was wrong about it, but couldn't tell when riding because I was also pedaling.
It is a variable speed. Up on a stand, with no pedaling, it definitely performs as it should.

There is too much snow down right now for me to re-test the PAS. But I'm confident in my original observations; as long as I pedal, it gives full assist. So, I can try what dogman said, just disconnect the PAS and use throttle assist only.

So anyway, if I want PAS to work better, is it time for a better controller?

 

[d8veh]

Everything is standard Chinese stuff. You're stuck with the full power from the pedal sensor, but the throttle normally takes precedence,so, if you open the throttle a little bit while pedalling, it should cut down the power. Can you confirm that, and then we can give you some options to make pedalling a bit more convenient. Is it too late to measure the controller?

 

[YoSamES]

Do you mean measure its dimensions?
98x67x35mm not including wires.

I'll try on the next ride to check out the effect of the throttle on the operation. We got a half foot of snow today, so the roads are messy. And worse, salty.

 

[d8veh]

That size means that there's enough room for alternative controllers. The KU65 from BMSBattery has a LED display, where you can set three levels of pedal assist plus it has a totally independent throttle. It's about $56 with shipping. The shipping is relatively expensive for a single item. It's always a good idea to get a pedal sensor as well to guarantee compatibility. I wouldn't rush into anything yet. You might be happy with what you've got once you've figured it out.

 

[YoSamES]

Thanks, I will report back.

 

[YoSamES]

I took a risky test ride down my snowy lane, then also tried the bike upside down on the bench.

Throttle alone = variable
Throttle on low, wheel minimally assisted, then begin to pedal = 100% assist, right away.
The throttle does not override the PAS. You could say the PAS overrides the throttle, though.

So probably the best first step is dogman's solution: Disconnect the PAS and just use the throttle.
And it sounds like if I want the multi-level PAS, then get the KU65 or equivalent.

Thanks for your help guys, and if I missed something, please say so.