So this one has been driving me crazy. I have a 2009 Sportster XL1200 Custom. I was getting a very sluggish crank, no start, and would end in the solenoid clicking (Drained battery). I pulled the battery twice and had it load tested at O'reilly's, and it comes back good both times. The bike will start once or twice, after reinstalling the battery, fresh from a charge and test at O'reilly's. I tried jumping the battery using a brand new boat battery I have in my garage, as well as my tahoe, and it still won't turn over. Slow crank, lights dim, and nothing. I removed the cables and nuts from the starter, cleaned, and replaced. Hooked jumper cables straight to the starter, and frame ground, and I'm still getting the same issue. A slow "Glug...glug...glug..."lights dim completely followed by solenoid click. Any suggestions? I've poured over google and forums, and haven't found a suggestion that worked. Any help would be greatly appreciated. Thanks dudes!

 

Remove, clean and reinstall the ground cable between the engine and battery.

When you reinstall the battery, make sure you follow the service manual instructions explicitly.

 

connections are a must as mr. dan mentioned.
load test is a good thing but must be done properly. on a fresh off the charger, you must do back to back tests, using the first test to remove surface charge. i prefer a load bank over electronic tester. a battery can have capacity issues, i assume it is the recommend battery.
have you tried to start with the battery out with direct connection to the slave battery.

 

Stop screwing around trying to jump start, that will tell you exactly nothing.

Why am I wasting my time when I get the feeling the OP is long gone...

 

i will tell you something. the machine will start independent of the stock batt & wiring.

 

You don`t need a separate battery and cables to troubleshoot a starting system, that is what people who are clueless do.

So you hook up a separate battery using jumper cables and what if it doesn`t start then (because of a problem with the cables on the bike)? Now you are on a wild goose chase...

No, screwing around with a separate battery and jumper cables is just that, screwing around.

Basic knowledge and sound troubleshooting practice.

The starting circuits on these bikes are very simple...

 

I have the Exact same issue on a 92 sportster. New batt., New starter, and cables. Did you ever solve the problem?