I've used the battery tender plus from Delton. I also have been using their lithium charger. Both for 2 different bikes. 

Neither of them is working correctly now, the lithium one is completely dead. The plus is charging and storing fine, but when disconnected it shows a load and charge, the terminals spark when touched which isn't supposed to happen. The terminals should be dead unless 3v is measured, a safety feature. 

 

Are there any good battery tenders out there other than these crappy ones? Both are only a couple years old. 

I got a like 5 Deltran chargers and Harley Davidson brand charger. Never had any problems with them on my 3 Harleys & 2 quads I keep them plugged in at all times when not riding. Seems like my softail battery still goes after 2 or 3 years even plugged in all the time. Other bikes haven't had any problems at all staying charged . I have the auto plugs so I don't see any sparks or anything like that.

6 minutes ago, Bzerk said:

I got a like 5 Deltran chargers and Harley Davidson brand charger. Never had any problems with them on my 3 Harleys & 2 quads I keep them plugged in at all times when not riding. Seems like my softail battery still goes after 2 or 3 years even plugged in all the time. Other bikes haven't had any problems at all staying charged . I have the auto plugs so I don't see any sparks or anything like that.

They worked well up until this spring. 

I wouldnt have been so concerned with the one that's still somewhat working but if the thing doesn't charge correctly it could kill the battery, or worse something on the bike or start a fire. I noticed it today after going for a ride I got home and the charge light was blinking and it was substantially warm. 

I'm curious how they both seemed to fail at the dame exact time, however a lot of reviews shows their fail rate it up there.

Sears stores are going the way of the dinosaur now, but this is the one I have. It charges bikes, cars, and boats. It works fairly well for trickle charging which seems like what you're looking for here.