Water shorting battery?

CJBull

New Member
Region
USA
New bike, and on the second ride I stopped at the top of a climb to take a drink, and when I started to go again, the pedal assist wasn't working. Display worked, but no power output. Conditions ranged from dry to snow/ice/slush/mud in shady spots, so some water/slush/mud got splashed up on the downtube. Nothing major, not like riding through water, just a small amount. Normal by any definition of off road riding. Next day, the bike works again. Dealer said something about the battery contacts getting wet/dirty, and that's been known to cause issues, but I'm unable to pull the battery and have a look because they sold me the bike without a battery key, and haven't been able to get a replacement.

Questions: Have any of you experienced anything similar? What was the cause? How did you resolve it? Do you take any steps to seal the battery contacts from water better?
 
Just to answer this thread before it vanishes, you can't do anything until you can get to the battery contacts. Either a key from the dealer or a locksmith. Once that's done, contact cleaner then a few drops of dielectric grease around the contact area will probably prevent reoccurring.
 
Water will conduct, but is not a good conductor unless it has road salt. On the battery contacts, it will not have an immediate effect because it will be no worse than a very dim light bulb drawing a small amount of current. It will not short out the battery, as you saw from the display being on. However, long term, you get electrolysis which will corrode/destroy the contacts. On a good bike design, if the battery is tilted, the contacts are near the top. Some batteries are backward and have contacts at the bottom. Worse, they have blade contacts that can sit in a pool of water.

On the other hand, water inside the control circuits has more effect. Sensors are low current devices, and if water is allowed to bridge a sensor, the effect may fool the control system into thinking the sensor is off or on. On my bikes, which were DIY conversions, I used to leave the throttle connectors exposed. If they got wet, the throttle shorted out. I fixed that.
 
You are going to want to sort that key out if you plan to ride off road. it is going to prevent you from cleaning and drying the frame and contacts in there, and that will cause problems in the long term. Most bikes have pretty low security keyways, so if the dealer doesn't have a key that works or can swap in a new keyway, I'd find all those old padlock keys in the junk drawer, and try them until you find one that works with a little jiggling.

A little dielectric grease or AC50 is a good idea to prevent the shorting, and keeping it clean so it doesn't hold water in there between rides.
 
You are going to want to sort that key out if you plan to ride off road. it is going to prevent you from cleaning and drying the frame and contacts in there, and that will cause problems in the long term. Most bikes have pretty low security keyways, so if the dealer doesn't have a key that works or can swap in a new keyway, I'd find all those old padlock keys in the junk drawer, and try them until you find one that works with a little jiggling.

A little dielectric grease or AC50 is a good idea to prevent the shorting, and keeping it clean so it doesn't hold water in there between rides.

I've read some horror stories about keys snapping off in the cylinder, etc. so I'm going to wait on the dealer a little longer before consulting a locksmith. The dealer is telling me that the key has to come from the manufacturer in Germany as it's specific to the bike and serial number, but they shut down around the holidays in Europe, and covid delays, and etc. So far the dealer has been responsive, so I'm going to trust they're doing their best.


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Typically the cases I have and have seen all have accessible lock sets. They use keys from other applications. Mine can use a Honda blank. Which brand or battery maker?
Sorry, I Googled the bike and I’m not helpful here.
 
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I've read some horror stories about keys snapping off in the cylinder, etc. so I'm going to wait on the dealer a little longer before consulting a locksmith. The dealer is telling me that the key has to come from the manufacturer in Germany as it's specific to the bike and serial number, but they shut down around the holidays in Europe, and covid delays, and etc. So far the dealer has been responsive, so I'm going to trust they're doing their best.


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its a bosch? if so lube it. all my abus locks need a good lube to be smooth.
 
A key for the battery finally arrived!

I promptly removed the battery to have a look around. Totally dry at this point, and was working just fine. I dusted off all the dirt that had found it's way into the battery compartment, reinstalled the battery, and no bueno. Removed the battery, cleaned the connections with some spray electrical contact cleaner, reinstalled....nothing. Pulled it out, blew it all out with compressed air, reinstalled....nothing. Thought about how finicky the connection seemed, grabbed the bike and bounced it on the floor a few times to maybe seat the connector....and boom, it works.

I'm really surprised at the lack of precision the bike/battery connection has for something engineered in Germany, but whatever. Guess I have that figured out.
 
No idea what model or motor, but Bosch with Intuvia can have issues with the display contacts.
 
A key for the battery finally arrived!

I promptly removed the battery to have a look around. Totally dry at this point, and was working just fine. I dusted off all the dirt that had found it's way into the battery compartment, reinstalled the battery, and no bueno. Removed the battery, cleaned the connections with some spray electrical contact cleaner, reinstalled....nothing. Pulled it out, blew it all out with compressed air, reinstalled....nothing. Thought about how finicky the connection seemed, grabbed the bike and bounced it on the floor a few times to maybe seat the connector....and boom, it works.

I'm really surprised at the lack of precision the bike/battery connection has for something engineered in Germany, but whatever. Guess I have that figured out.
Glad it worked for you but really, brute force shouldn't be the answer when dealing with expensive and delicate items. Keep that key safe.
 
It's a Bulls E-stream Evo AM3 with Brose Mag S and 750wh "super core" battery. Only one internal connection that looks identical to the external charge port, and it seem to be mounted on a swivel or rubber mount or something that allows it to move around a bit.

Now that I have the key, and can get the battery out, I'd almost just like to remove the lock cylinder entirely so that I can remove/install the battery with a screwdriver instead of a key. It's not like I'm going to leave the bike unattended anywhere that anyone will have a chance to steal the batt.


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It's a Bulls E-stream Evo AM3 with Brose Mag S and 750wh "super core" battery. Only one internal connection that looks identical to the external charge port, and it seem to be mounted on a swivel or rubber mount or something that allows it to move around a bit.

Now that I have the key, and can get the battery out, I'd almost just like to remove the lock cylinder entirely so that I can remove/install the battery with a screwdriver instead of a key. It's not like I'm going to leave the bike unattended anywhere that anyone will have a chance to steal the batt.


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Before you go that far, if you are handy, pull the cylinder and remove a couple of the wafers/pins (Lots of google videos on how to rekey a cylinder). That way it looks and feel secure, but can be opened with pretty much anything. I did that on my mothers old IZip bike as the keys walked away a long time ago, and once I picked it open, I reset the wafer locks to use two very closely matched wafers only. It looks secure and keeps the batteries safe, but can be opened with a bobby pin if needed.
 
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