Shenzhen Songi electric bicycle from China

[jjackstone]

Frank,
Sounds like the pedals are there just for looks. Without the pedals it's probably considered a scooter and would need some sort of licensing. If I remember the laws correctly, the Federal speed for considering it a bicycle is 24 mph. Here in CA, the speed is 20mph. Anything above that can get you a speeding ticket. I've been fortunate enough to have been clocked at no more than 18mph so far.
I always thought it humorous that I can actually legally ride my regular bikes faster than my electric.
JJ

[Frank Lee]

I'm getting the gist of this thing now.

There are two ways to activate the electric motor; one is with the twist grip throttle, and the other is to pedal for about 2 or 3 seconds; there is a sensor that notices the pedalling and kicks the motor on.

I like the idea of starting off by pedalling til the motor kicks in; starting out is probably the biggest amp draw so that little bit of pedalling (and having the motor kick in after it has the rolling start) could be conserving the juice quite a bit. I use the twist grip after that for cruise.

Also I took it up a steep hill today and pedalled even though I didn't have to- again, "hypermiling" the batt pack. If only pedalling a regular bike up that hill was so easy! I went several miles and the indicator still said full charge when I got home.

I've found that "1st gear" on the electric controller is pretty much as fast as I need/want to go around here. Staying in 1st has gotta extend the range vs. using the higher "gears" (remember, the motor is in the hub so no real gears). When I come to a rise and if I'm going slow enough, I'll pedal to help out- more hypermiling. But it's a fixie and the pedalling gear is pretty low. I need to look and see if a larger chainwheel can be fitted, or maybe even a sprocket cluster and derailleur, because I would like to "help out" with the pedalling more than it allows me to now.

I've used it for grocery shopping several times. The basket and racks are nice for that. Very handy!

I've decided it wouldn't be wise to use it's bits to electrify my ATB. That would ruin the value of it. Better to get other motor/batts for that project.

cf: Wasn't me that went to any EV meeting...

[NiHaoMike]

Originally Posted by jjackstone

Frank,
Sounds like the pedals are there just for looks. Without the pedals it's probably considered a scooter and would need some sort of licensing. If I remember the laws correctly, the Federal speed for considering it a bicycle is 24 mph. Here in CA, the speed is 20mph. Anything above that can get you a speeding ticket. I've been fortunate enough to have been clocked at no more than 18mph so far.
I always thought it humorous that I can actually legally ride my regular bikes faster than my electric.
JJ

One solution is to build a bike that can only operate in hybrid mode. Use a HSD transmission so power can be accurately measured. Then have a knob to adjust the "virtual gear ratio" and a knob to adjust the "power split ratio". ("Power split ratio" refers to how hard the batteries can work. For example, it could be set so the batteries can supply as much as 10x the power supplied through the pedals.) It can then be allowed to go faster than 20MPH since it would be a pure hybrid - don't pedal and it will not accelerate at all. You can say it's just a bike with an electronically controlled CVT.

And what would happen if you coast downhill faster than 20MPH? Moreover, would a ticket even be valid if the bike does not have any instrumentation for measuring speed?

[cfg83]

Frank -

Originally Posted by Frank Lee

...

I've found that "1st gear" on the electric controller is pretty much as fast as I need/want to go around here. Staying in 1st has gotta extend the range vs. using the higher "gears" (remember, the motor is in the hub so no real gears). When I come to a rise and if I'm going slow enough, I'll pedal to help out- more hypermiling. But it's a fixie and the pedalling gear is pretty low. I need to look and see if a larger chainwheel can be fitted, or maybe even a sprocket cluster and derailleur, because I would like to "help out" with the pedalling more than it allows me to now.

I've used it for grocery shopping several times. The basket and racks are nice for that. Very handy!

I've decided it wouldn't be wise to use it's bits to electrify my ATB. That would ruin the value of it. Better to get other motor/batts for that project.

cf: Wasn't me that went to any EV meeting...

Ha ha, "virtual gearing" ala digital zoom on cameras. I will keep that in mind. We are "E-Bike" distance to a grocery store, so that would be a plus. The EV meeting was old memory for me, so I "congealed" as your experience (stupid brain!).

CarloSW2

[jjackstone]

And what would happen if you coast downhill faster than 20MPH? Moreover, would a ticket even be valid if the bike does not have any instrumentation for measuring speed?

Let me clarify. The speeds I quoted are on a level surface with both the electric and human powered motors activated.
As for the ticket being valid without having instrumentation, try gettng caught doing 80mph in a car and blame it on no speedo.
JJ

[NiHaoMike]

Originally Posted by jjackstone

Let me clarify. The speeds I quoted are on a level surface with both the electric and human powered motors activated.
As for the ticket being valid without having instrumentation, try gettng caught doing 80mph in a car and blame it on no speedo.
JJ

I think it's different since I believe speedometers are required by law on cars (or at least standard equipment) but there are plenty of hybrid and electric bikes, as well as just normal bikes, that do not have speedometers.

Since the restriction is only for level surfaces, add a sensor to limit it only on level surfaces.

[blueflame]

Cool bike. I wish I didnt sell my electric bike now.

One thing I noticed on different electric bikes was the placement of the controller. Some cooled nicely as they were exposed to windage, and some were tucked away and got too hot. Should be an easy mod to make sure they keep cool. Usually there is a overload switch somewhere to prevent burnout too.

One way to check your batts for the future is to put a voltmeter across each batt, place the front wheel up to a wall, sit on the bike and open the twist grip. Do this briefly and watch for volt drop, moving through all the batts individually. 11.8v is probably a good cut off for a failing battery

[Frank Lee]

Thanks for the battery test suggestion!

I did overload the controller once by flipping through the "gears" without letting up on the "throttle". Had to pedal the dang thing until things cooled off enough for it to kick back on. No harm done though. Note to self: release throttle when changing "gears". While that is the only time I've overheated anything, should it happen again when it isn't my fault I will look into the cooling situation. The controller is completely enclosed in bodywork now.

I want to fit it with a bicycle computer as there is no speedo/odo, but none of the stock mounting points fit. I will have to fab up my own. When I have access to that data I want to track miles, time, and speed vs battery drain. For example yesterday I started with a 100% charge, went 4 or 5 miles (?) then it took 2 hours to top off the batt pack when I got home. That inverse relationship of riding time vs fuelling time is the biggest thing to adjust to re: electrics for me.

[Frank Lee]

Pics:






LOVE the fold-out racks!

[jeffrey110]

Hi, i got the same bycycle as frank lee and same problem with power can some one please help me .what kind a converter do i need to charge this electric bycycle here in newyork PLEASE HELP ME.thanks