My ebike is too torquey, how do i settle it down a bit?

[TroySmith80]

This may be an uncommon question. I just put together an ebike. I'm building a mini-velo cargo bike. It's an Origin-8 Bully that i'm building large front and rear racks on and i'm using it as a commuter and cargo bike. I put an ezee geared motor in the back wheel with a 48v battery and an infineon 12 FET 4110 MOSFET MK2 sensorless Controller LYEN Edition controller.

I'm not sure exactly what the specs are on the motor, I put it together from parts of a couple of bad motors (with help from Bend Electric Bikes), but from a stand still, or at very low speeds, it has a lot of instant torque! The thing actually flipped me over backwards the first time i rode it. This is largely due to the extremely short wheelbase of the bike (i have plans to extend it). Even after the bike is extended and made more stable, i'll still want a little smoother acceleration for riding around pedestrians and in low-traction or tight situations. Once i have a little speed up, it's fine, there's not so much power that it's still so abrupt then, but at low speeds it can be very jerky and abrupt.

I don't want to limit power all the time, like when going up steep hills, but i'd like to somehow limit the power when i'm at low speed, say under 7mph or so. Is there any way to do this?

 

[biohazardman]

I have heard good things about these and he just got another run done.

.http://endless-sphere.com/forums/viewtopic.php?f=31&t=59631&p=895292&hilit=throttle+tamer#p895292

 

[DAND214]

Geared motors don't normally like sensorless controllers.

Is the start out smooth or stutters then goes? If so maybe you might want another controller.
Do you know what the settings on the controller? battery amps and phase, if too jigh that can cause a sudden jerk if not a smooth start.
Put a 3 speed switch so you can cut the low speed down till moving.
And if the amps are too high you might/will ruin the clutch or gears.

Dan

 

[TroySmith80]

Throttle tamer looks interesting, ramping control is just the sort of thing i was hoping for, that with the acceleration factor as well could be perfect.

As it is, it is smooth as long as i am very careful on the throttle application, but if i'm not paying close attention, it's easy for the front wheel to come up, or at least to lurch ahead more abruptly than i'd like.

Is that controller not a good match for the ezee geared motor? I thought it should be fine.

 

[biohazardman]

I have had several controllers on my BMC geared motors and none have been perfect, throttle wise, but with some programming and a bit of careful control on my part I can live with it. The higher my batt voltage the harder throttle control becomes in my case anyway. Will be trying a throttle tamer soon as it arrives. Yes, the three speed switch mentioned might help I have not tried it as I don't want more stuff on my handlebars. Right now, at 66-72V, I am still fighting trying to keep the surging under control at less than 28MPH. Acceleration is fine if I go easy on the throttle at first as is cruising at 28+ but it would be nice to cruise at a more reasonable speed in the hood.

 

[Arlo1]

I have not used one of Zombies throttle tamers but it will make your life a lot better. All these china controllers have a pour throttle control and they are basically a speed based setup. So it will give you a burst at low throttle settings until you get close to the speed the throttle is set for. More expensive controllers base the throttle on the motor (phase) amps and this gives a perfectly smooth throttle feel.

 

[Bluefang]

Just checking, on the controller do you have the block time set to 0.1 or the lowest it can go? Also try setting the phase amps slightly lower as they will help limit the start up current and not effect the actual power once up to speed that much in comparison to the battery current limit.

Lyen controllers and generally quite smooth. greentime controllers are another matter

 

[TroySmith80]

Thanks for the replies everyone. I don't have any idea what the current programming is, i don't have a USB cable for the controller. I'll have to get one and see how things are set up.

Would a v3 cycle analyst be able to improve the throttle? I kind of want a CA but haven't really felt compelled enough to spend the money and to clutter up my handlebars. However, if it could solve this problem as well as providing all the handy information, that might push me over the edge.

A 3-speed switch would be some help, but it's not the most elegant solution. I'd still like to have full power available without having to change anything, i just want more controllable delivery at very low speeds. I don't want to have to switch it up for a hill and then remember to switch it down when i slow down in order to not be surprised when i hit the gas again.

 

[Arlo1]

You guys don't know what smooth us until you try torque throttle. I forgot to mention a CA has a throttle output so you can use it as a throttle tamer as well.

 

[liveforphysics]

You guys don't know what smooth us until you try torque throttle.

+1

Lebowski control FTW.

 

[bionx 1954]

Hi I have a 9c that I run with a sensorless controller. I had similar problems. A Cycle Analyst is a excellent investment for many reasons, but 1 feature is that you can set the limit on how much power goes to the motor ( current Amps). On starting off from a stand still uses the MAX AMPS, So I used trail and error until I found the right setting that allows a smoother start. In my case it was under 40A. Once you are moving and need to go up a hill normally the current demand is less then that of a standing start. Hope this helped As far as a C.A.( Cycle Analyst) "I Wont leave home with out it"

 

[teklektik]

This may be an uncommon question....

... I put an ezee geared motor in the back wheel with a 48v battery and an infineon 12 FET 4110 MOSFET MK2 sensorless Controller LYEN Edition controller.

...from a stand still, or at very low speeds, it has a lot of instant torque! The thing actually flipped me over backwards the first time i rode it. ...at low speeds it can be very jerky and abrupt.

I don't want to limit power all the time, like when going up steep hills, but i'd like to somehow limit the power when i'm at low speed, say under 7mph or so. Is there any way to do this?

Actually not uncommon for the larger gear motors.

Although it's a bit expensive, I recommend installing a CA V3 (not the older V2 design). Here's a recent post on a similar topic that has some recommendations, a bit about Current Throttle, and V2/V3 differences - read it. Although you can play games with controller phase amps or otherwise limit the controller max amps to make the take-off or throttle more manageable, the V3 lets you instead set current limits for best performance without compromise for controllability.

CA Current Throttle operation is basically a fly-by-wire system where the operator throttle goes only to the CA to tell it what is desired and the CA then runs the controller throttle to make it happen. All the tiring continuous 'death-grip' throttle adjustments become the responsibility of the CA - not the operator. You turn the throttle to tell the CA: "give me 1.5A!" and the CA makes it happen - no matter how twitchy the controller/motor might actually be...

• FWIW - I run with two BMC V2S gear motors (similar to MAC 8T) at a nominal 64v (73v HOC) - this gives it more than twice your torque and essentially unridable native throttle response. But - using a V3 with Current Throttle and CA 3-speed switch, the throttle is easily controllable to give sub-100W power control for slow bike path use, allows slammed WOT off the line with a smooth as silk getaway, and gives nice linear throttle control up to 40mph. The V3 makes it a real pleasure to ride...

 

[TroySmith80]

more great info, i'm glad i asked! Thanks for the responses. Maybe a CA V3 in my future.

 

[Arlo1]

more great info, i'm glad i asked! Thanks for the responses. Maybe a CA V3 in my future.

I used a CA in one of my bothers electric BMXs and it worked well. It was not perfect but better. You can not get a perfectly smooth throttle without measuring the Phase amps.

 

[nicobie]

I've never used the CA v3 but I'm sure that it will help. If you can find a clyte analog controller, your problem will be solved.

 

[Solcar]

Torque of the motor depends the current going into it. Controlling the current instead of the voltage can give a smoother feel. Many or most controllers basically regulate the voltage to the motor, with an over-current cut-off. I prefer a current regulator that has that same final current limit.

 

[Arlo1]

Torque of the motor depends the current going into it. Controlling the current instead of the voltage can give a smoother feel. Many or most controllers basically regulate the voltage to the motor, with an over-current cut-off. I prefer a current regulator that has that same final current limit.

There is a difference between the current on the battery side VS the current on the motor side. This is where the time needs to be spend for torque throttle. All done on the motor side.

 

[dirtbiketoebike]

I come across the same here. Glad to see this subject pop up again. Search engine is so long at times and glad to see new opinions or options with new inventions. Going to read the throttle tamer thread one more time but that looks like my option,definitely want a better controller in the future tho.
I have a 1500 watt motor and was running 40 amp 48v controller. Then bought a Chinese 48,60,72v combo controller probably 40 amp one. I usually run it at 72v. At 48v the throttle is smooth. At 72v it wants to pop the front wheel unless i micro twist the throttle...I like that when im moving but at dead stop it's an issue. Had an extra one of those controllers and put the bike on a work stand and ran 88.8v nominal and 100.8v hoc. Controller seemed to handle it fine. Haven't tried on land yet but looking forward to it. At 74v nominal it did 43 mph with 5 amp hours. I have more amp hours just need to finish my battery housing. With the 88.8v nominal,100.8v hoc I'm hoping to do 50 mph. But thinking maybe 47-48 mph. After testing the top speed briefly I will bring down the voltage series until I get my throttle response smoother. Thanks