Clean your battery contact posts - Estream Evo 3 27.5+

Bully

New Member
#1
I bought my Estream Evo 3 27.5+ hardtail in Sept of 2018. I've ridden it quite a bit since then without any problems.
It has been a wet winter here in northern California so I have ridden through mud and wet conditions. I have washed my bike several times with a hose at low pressure.

In all the time I have owned it, I have never removed the battery. I always recharged with the battery in the bike.

With all the caveats out of the way, this past Saturday (3-30-19), while riding off road, the motor assist level kept going back to zero on its own. I kept an eye on the display and noticed that it would blank out and then come on again. In essence, it was turning itself off and then back on again. That's why the motor assist level was reset to zero.

I deduced that it was briefly losing and then regaining battery power. I removed the battery for the first time and I noticed that there was a blue-green material on the battery posts. I cleaned those off with isopropyl alcohol and reinstalled the battery.

I took a ride today (4-2-19) and everything is fine.

So if you experience the same problem, try cleaning your battery contact posts.
 

The duke

Active Member
#3
Wow! You should do a test and douse it with water, then pop it open and feel inside to see how much water, if any is getting past the seals. If it's a lot, that might be a warranty issue.
 
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LimboJim

Active Member
#4
You might want to add some dialectric grease to the contacts, as that might help stave off future problems. I put a small amount of it on all my ebikes' contact points.

My Estream EVO FS3+ has the same battery setup and most times I charge it on the bike, though periodically I remove the battery and clean up in there.

2+ years and at least 50 charges later, no problems to report here (knock wood).
 
#5
I clean my connectors with Deoxit D5 contact cleaner.

Its non conductive and supposedly treats the contacts. Been using this on my RC drone batery connectors (which pull about 120A peak) for years.
 

Bully

New Member
#6
Thanks a lot for the suggestions. Fortunately the rainy season is about to end here in northern California.
The contacts are clean now so I don't think I need contact cleaner.
I found that they sell dielectric grease at my local O'Reilly auto parts store. They sell a small pack for $1.49.
 
#7
Had that happen to me. Traveled well out of town for a group ride. They all took off into the distance and I was left back in the carpark with no power. The display comes on but there is no power to the motor. Has happened 3 or 4 more times (over 2 years) and found that removing the battery and pressing the spring-loaded contacts on the bike solves the problem. I never remove the battery for charging. On one of the very rare occasions I did remove it I found that you MUST remove the key before rotating the pedals. The key does not work when in two parts. :mad:
 

LimboJim

Active Member
#8
Had that happen to me. Traveled well out of town for a group ride. They all took off into the distance and I was left back in the carpark with no power. The display comes on but there is no power to the motor. Has happened 3 or 4 more times (over 2 years) and found that removing the battery and pressing the spring-loaded contacts on the bike solves the problem. I never remove the battery for charging. On one of the very rare occasions I did remove it I found that you MUST remove the key before rotating the pedals. The key does not work when in two parts. :mad:
If you haven't already, you can replace your broken key here: https://mobilesecurity.abus.com/eng/bike/keys/keyordering