A worn sprocket could not cause as much of a loss of energy as you have mentioned we would look elsewhere for the problem.
It could be a problem with the battery pack or with the battery charger. At 12.5 Volts the batteries are only at an 80% state of charge. The batteries should be at 13 Volt after being recharged and resting if they were to be at a 100% state of charge.
The problem could also be with the motor. If the motor is consuming too much power it would have to convert it into heat and would get very hot so that is something to check for.
We would test the output Voltage of the charger to see if it is outputting the correct Voltage which should be around 28 Volts. This is only a basic test of the charger and it will not determine if the charger is operating properly throughout its different charging stages, however, if the charger has a low output Voltage then that could point towards it being faulty.
Hi Heather, my apologies for this very late reply. It sounds most likely to be a problem with the battery pack.
Sometimes a battery pack will pass a load test for a few seconds, however, the battery pack will not last very long under a longer load time such as 5 or 10 minutes. I have seen this happen before. If there is a problem with the batteries then they could be at an 85% state of charge, however still have a very low capacity and run out of power faster than normal.
The 27.2 Volt output of the charger is acceptable and it should be able to charge the battery pack up to a 100% state of charge level which is 26 Volts for a 24 Volt battery pack.
The next step that I would take is recharging the battery pack for a full 48 hours to try to equalize the cells in the batteries and get the battery pack up to a 100% state of charge. During this 48 hour charge, the battery charger should be left on after its light turns green as this is when the charger is in its saturation stage cycle which will attempt to equalize the cells in the batteries.
Ok, so the after the 48 hour charge I did another load test. This time both batteries were at about 13.4 sitting and 11.9 under load. HOWEVER, then I took a ride for 5 minutes (in which I had no hill climbing ability). When I got back the front battery was at 12.6 and then 11.7 under load and the back battery was at 11.1 to 9.4 under load.
So is it time for a new battery pack? Which one do you suggest? Is there one that will help my hill climbing ability?
Your most recent load test results indicate that the battery pack needs to be replaced so according to the test results it is time for a new battery pack.
We carry both standard range and extended range battery sets for the eZip 750 electric scooter. The extended range battery set will provide a longer range or runtime than the standard range battery set, however, it will not provide better hill climbing ability.
The hill climbing ability of the scooter is regulated by the scooter's controller and motor, and not by its battery pack, so there is nothing that can be done to improve the scooter's hill climbing ability by changing the battery pack.
Either the standard or extended range battery pack is well suited for the eZip 750 scooter so it is a matter of whether you will use the extra range provided by the extended range battery pack to determine if it is worth the extra cost.
One more thing worth mentioning is to check and see if the battery pack wiring harness is soldered onto the batteries or not before you purchase new batteries. If the harness is soldered onto the batteries then a new battery pack wiring harness will need to be purchased in order to install the new batteries.
All of these parts are available on our eZip 750 and E-750 Electric Scooter Parts page.
Your test results for the new batteries are normal so they should not be causing the problem. The range will increase as the batteries are discharged and recharged several times until they are fully formatted. Formatting the batteries will not increase the power of the motor though.
Since the power of the motor is significantly less than it used to be that most commonly points towards a problem with the motor. The magnets in the motor could be demagnetized due to old age or hard use, or the coils in the motor could have burned winding insulation and no longer be performing like new. Both of these motor problems can cause a loss of power and excessive power consumption from the battery pack.
Troubleshooting vehicle electrical problems can be hit and miss so I cannot guarantee that the motor is causing the problem, however, since the batteries are new, the motor is the most likely part to be causing the problem.
So it sounds like if I want to keep using this scooter I should buy I new motor. I see that you have two replacements - a fixed and a freewheel. I believe the one I have now is fixed. Any advantage to switching to a freewheel? I am considering cutting my losses with this scooter and starting over with an Uberscoot 36Volt 1000W. It looks like if I can keep the new SLA batteries I just bought alive, they would work as 2 out of 3 replacements for the Uberscoot, is that correct?
Switching to a freewheel sprocket will allow the scooter to coast better when the throttle is released which can help to provide a longer ride time. The fixed sprockets are 11 teeth and the freewheel sprocket is 15 teeth so a longer chain would be needed and the gear ratio will be a little higher with a 15 tooth sprocket so it might go a little faster, however, will accelerate slower and have less hill climbing power.
As long as the eZip batteries have the same dimensions as the Uberscoot batteries then they can be used as replacements. I believe that the Uberscoot 1000 Watt scooters use 12Ah or 15Ah batteries though which are a bigger size than most eZip scooters use.
This is a little more complicated than it appears because when a battery pack is replaced all of the batteries in the pack should be the same brand, model, and age. Due to this, two batteries that have been in storage for a while would not be a good choice to install along with two brand new batteries to make a 48 Volt battery pack.
Regardless of this, the best way to keep electric scooter batteries which are in storage alive is to recharge them every 30 days. This will keep them alive while they are in storage.