Assistance cut out

[Terry Nye]

Hi all,
I am a new memeber here and completley new to any e bike build, i am very experianced in building cycles.

I have recently stripped an E Mission trike that was giited to me as used but well cared for from an elderly friend. I know they indoor stored the battery, had no issues with it losing charge quickly or acting intermitantlly. I need to check the ampage but it is a 250W friont hub motor. They did have a new display fitted at one point.
I have built it onto and ex GPO Mailstar as the wheel was the same size.

I find it gets to no more than 12.5mph and cuts assist. Reading up there seems to be lots of possible issues, such as:
Battery is old and not fully charging or intemmitant-it seems to charge ok, hold charge ok and doesn't falter in apllication. It does not run down premetually.

Wiring connections-all checked

Sensor-cleaned as I refitted the crank

Controller- unknown but all connected ok

So how do I check the battery life? there batteries are diffwent to many others in sdize and shap and i would have to get a rack battery and modify bike to replace it.

Could it be the controller was set at a lower speed as this was a trike originally and they can be unstavble at speed and because of the frame design their target audiance would nbe less mobile or older customers?

Any other things to check?

Shall i replace the controller?

Thank you in advance

 

[Az.]

Check the wheel size on display.

 

[Terry Nye]

Hi there,
I will check the display wheel size thank you. The hub and wheel size are as original all i did was move it all from the trike to the Mailstar. I will check wheel size today and gte back to you.
Thankyou Az

 

[Az.]

Hi there,
I will check the display wheel size thank you. The hub and wheel size are as original all i did was move it all from the trike to the Mailstar. I will check wheel size today and gte back to you.
Thankyou Az

Yes, but I am guessing trike wasn't built with speed in mind. Perhaps owner didn't notice or didn't want speed to be to high.

 

[saneagle]

Lift the wheel off the ground and spin it up to max speed. That will tell you if it's a battery problem. Do it with a fully charged battery, then do it again with a nearly empty one. If you get a significantly different speed, say 10% difference, you're limited by the motor. If the speed is the same for both tests, you're limited by the controller.

 

[Terry Nye]

Yes, but I am guessing trike wasn't built with speed in mind. Perhaps owner didn't notice or didn't want speed to be to high.

No the gent was elderly and only did a few miles at low settings and although i rode it a few times after minor adfjustments i never had the need to max out on speed and so wasn't aware.

 

[Terry Nye]

Lift the wheel off the ground and spin it up to max speed. That will tell you if it's a battery problem. Do it with a fully charged battery, then do it again with a nearly empty one. If you get a significantly different speed, say 10% difference, you're limited by the motor. If the speed is the same for both tests, you're limited by the controller.

Thank you I will try that.

 

[Terry Nye]

Yes, but I am guessing trike wasn't built with speed in mind. Perhaps owner didn't notice or didn't want speed to be to high.

Hi there
Thankyou for the advice the wheel size on the settings is correct. Another ride today confirms it stops assisting at 12.2mph. I have just got a voltmeter to test battery and charger.

 

[Benjahmin]

Being a trike, and therefore likely to be for less able/older folk, could it be that the 12mph is set as max speed in the controller?
Given the handling eccentricities of delta trikes this would make some sense.

 

[Nealh]

One suspects the speed restriction may just be the motor rpm winding on such vehicle , though as d8veh has said amotor speed test with a charged and near empty battery will give an inkling.

 

[Terry Nye]

Hi all,
ok so checking further the charging lights weren't showing on the battery. I assumed that was just that. But when I put it on the bike the display shows charge and the motor does cut in as normal, but stops assisting at 12.2mph exactly and consistantly. I though therefore the battery had been charging and the lights were faulty?
I put a voltmeter on the battery charger shows 42v, the battery shows nothing??
If there is a fuse in there where would it be?
But why is the motor still assisting. I have only done a few miles since building it, my only assumption was the battery was fully charged and then the fuse blew?? Photos attached for all you clever people out there.

Confused now?

 

[saneagle]

Hi all,
ok so checking further the charging lights weren't showing on the battery. I assumed that was just that. But when I put it on the bike the display shows charge and the motor does cut in as normal, but stops assisting at 12.2mph exactly and consistantly. I though therefore the battery had been charging and the lights were faulty?
I put a voltmeter on the battery charger shows 42v, the battery shows nothing??
If there is a fuse in there where would it be?
But why is the motor still assisting. I have only done a few miles since building it, my only assumption was the battery was fully charged and then the fuse blew?? Photos attached for all you clever people out there.

Confused now?

It shouldn't be that difficult. Switch the bike on and try it. If the bike works, the battery isn't zero volts. If the bike doesn't work, what did you do to it to stop it from working?

 

[Terry Nye]

It shouldn't be that difficult. Switch the bike on and try it. If the bike works, the battery isn't zero volts. If the bike doesn't work, what did you do to it to stop it from working?

Thanks but as stated you can feel the power work, it cuts out at 12.2 mph not the 15.5mph as expected. But battery charge light doen't illuminate when plugged in, the charger shows 42v I can't get a reading off the battery. The bikes display shows as 3 /4 charged at last use.

 

[saneagle]

Thanks but as stated you can feel the power work, it cuts out at 12.2 mph not the 15.5mph as expected. But battery charge light doen't illuminate when plugged in, the charger shows 42v I can't get a reading off the battery. The bikes display shows as 3 /4 charged at last use.

Why do you expect 15.5 mph? Some bikes are designed for 12 mph, which was the max legal speed before UK officially adopted EN15194 about 10 years ago.

 

[flecc]

Thanks but as stated you can feel the power work, it cuts out at 12.2 mph not the 15.5mph as expected. But battery charge light doen't illuminate when plugged in, the charger shows 42v I can't get a reading off the battery. The bikes display shows as 3 /4 charged at last use.

That is normal and by design on most upright trikes. That's because they tend to be somewhat unstable in some circumstance and large numbers never get used to their steering characteristics, so they are rarely specified for 15.5mph assistance.

Some are even slower when the maker sells them with a choice of two different wheel sizes, the one with smaller wheels being even slower. And the Di Blasi folding trike with e-drive only runs to about 8mph and if you ever tried one, it's as fast as you would ever want to go on one.
.