I got the H-D tender. As good as any of them.

 

just had the 5000 mile service done so oil should be ok

 

I don't know of any that are set up to charge two batteries at once but the ones at Wal-Mart are only about $ 15.00, buy 2 or just alternate them every other week or so.

 

Battery Tender's are availible with multi conectors.If you search on the net,there are a few places that sell them and have all the info you want.