Update: After I showed him the video I have of the bike going "clunk," the service writer at my local dealership would've bet money that my battery was the culprit even though it's just over a month old. He also said he's never had to replace a Sportster starter, which is not the same as saying he hasn't had to repair them. I took the battery to my local auto parts store and it load tested perfect. My next step will be to measure the voltage at the starter, try to spin it by jumping it directly and not through the ignition switch and relay, and if those don't show the problem, I'll open the solenoid and check the condition of the plunger and contacts.

Clarification: I know the engine isn't locked up because I can roll the bike clutch out in 5th gear and hear the engine turning over, but the starter won't kick in in gear or in neutral.

 

I am now the proud owner of the 2007 HD Sportster Service Manual, which makes me dangerouser than I was when I was a member of the great unwashed. Two things jump out at me reading the section on the starting system: the electrical gizmo under the battery (TSS/TSSP) is both the turn signal flasher and a lean angle sensor that shuts off the engine if the bike goes down and prevents the starter from working until reset. My daughter dropped the bike on the left side just before all this non-starting happened. In fact she skinned up the clutch lever base and twisted it around the handlebar 15 degrees or so. I loosened the Torx screws and put it back into position afterward. So another place I need to check is the function of the clutch switch that's supposed to let you start the engine while the bike is in gear but the clutch is pulled in. And the last thing I need to check is the cleanliness and contact of the starter relay connection on the solenoid. A friend told me sometimes that connection can get crudded up and keep the starter bendix from engaging. The starter motor spins freely when I apply 12V directly to the solenoid's + battery terminal. I tried swapped the starter relay and the system relay just below it. They're the same relay and I figured if the starter relay was bad the system relay would cure the problem. No help. If the tests of the starter circuits pass, I'm going to pull the primary cover and take a look at the business end of the starter and the ring gear on the clutch basket.

Have any of you installed the "stronger" starter kit that replaces the clutch basket and the starter pinion gear to compensate for the high compression engine, and oif so, did you think it was worth it? If the starter pinion gear and/or the ring gear turn out to be the culprit, I would consider the upgrade as good insurance since this is a very low mileage bike and shouldn't be having starter problems.

 

Coincidence, I was just looking at another thread about that lean angle sensor. No doubt your new manual explains how to clear it. Nothing's going to happen until you do. Good luck with the battle!

 

Read the voltage at the battery posts (not at the battery cables).

Now press the start button, and read the voltage while the start button is pushed.

What are your voltage readings?

 

Check for compression releases. I also get a clunk whenever I forget to press the compression releases.

 

Since I couldn't find the problem on the right side, today I pulled the primary cover expecting to see some damage to the ring gear or starter pinion. Nope! Everything's clean and free of shavings, etc. I tried the starter and saw first hand that the Bendix fully engaged but the starter motor isn't turning the engine at all. I pulled the plugs again so there was no compression. No change. I removed the starter to give my HD service department something to do tomorrow.

Have any of you even had troubles with the TSS/TSSP, the turn signal and lean angle Gizmo under the battery? The manual says it resets by turning off the key them turning it back on again, but if it's bad it might cause with I'm having.

 

If the TSSM was causing the issue, the starter would do nothing, the pinion gear would not extend into the ring gear.

Your troubleshooting ideas are way out in left field...

Pulling the starter was a waste of time.

The starter circuits are very simple to troubleshoot.

You came here asking for help but you have ignored suggestions.

Do you want to fix this problem or ramble on with your wacky guesses?

If you actually want to find the problem, get out your voltmeter and listen to the troubleshooting advice given.

 

Does the starter make a "zzzziiiinnnnnggggg" sound when you hit the button? If it does, it's the one-way clutch inside it that's busted.

Cheers!
.

 

No Zing and the one way clutch is fine.

 

I didn't ignore suggestions, but there were some I didn't see on my "smart" phone. As you suggested, I've now had the new battery load tested twice, and I cleaned all the connections to practically zero resistance.

I took the new battery, a 200 CCA, and the old one, a HD AGM 225 CCA, to a different shop and had both load tested. Both passed needing only a little charge.

I reinstalled the new battery and tested the connections again. Voltage across the posts with the key off measured 18.6V. That's not a typo, and it repeated several times there and at the ends of the cables. Key on, very slight drop to 18.4V. Run dropped it to 18.3 when the fuel pump primed. Start dropped it to 9V, 8V and 7V in just a few seconds. I got 7V on the other side of the solenoid going to the starter motor. I have no idea why a 12V battery would test at 18V but the meter was set right and when I removed the battery from the bike, the battery measured 14.4V across the posts.

I installed the old HD battery and it tested at 14.2V at the posts and cable ends. Key on gave 14.1 and 13.9 when the fuel pump cycled. Start gave 7 then 6V each time I tried it, with 7V at the motor side of the starter. Clearly neither battery has enough juice by itself to turn over the engine. Although using a jump box when this problem first began didn't help, I'm tempted to jump one battery with the other to see of their combined power will start the engine.