First thing I would check, is battery cables and voltage drop. Use a good DVOM to test it during cranking from the battery LUG. Not the cable attached to the battery. If you have a poor connection at the cable from the lug, you'll miss it by testing attached to the cable end. Run the positive lead to the lug on the battery and the other lead to the positive on the starter post
. Again. Not the cable end.
Set the meter to peak voltage and crank/start it. Read the captured voltage peak and see if it's over 900 M/A or more. It could go as high as 1.2 volts. Anything beyond that is an excessive voltage drop. Do the same thing on the ground side. Just switch the leads. Neg. on battery lug and positive on the ground strap bolt. Not the cable ends
. It should read below 1.2 volts while cranking also I would shoot for 900 M/A or less, myself.
The most overlooked problem is loose battery cables at the battery. People just don't understand the value of properly tightened battery cables. Check them with a 10mm socket. Not just looking or wiggling. Use a socket and ratchet to tighten them down. Heat and vibration makes the contact of the cable change. After it cools off, the bike will have enough contact to start again. Don't be fooled by a simple loose battery cable. Most dealers will never check the basics and you'll keep having this problem.
Start with properly checking the cables and move to the voltage drop test, if necessary.
You also want to make sure your battery voltage isn't dropping below 9 volts with the starter engaged. Anything under 9 volts is a problem and I like to see at least 9 to 9.5 volts while cranking.
I'm a geek and use my Pico DSO to check this stuff. Here's an idea of what I'm doing. Voltage drop tests are quick an easy with a DSO, but a DVOM works too.
This is a VDT and a current draw test on my truck. It's the same thing on a bike, just lower current usage from the starter. The red line represents amperage/current draw. The blue line represents battery voltage. Battery voltage at key on, then to crank/start mode and back to run mode after the engine starts. You can see the voltage rise as the alternator starts charging. This voltage drop is critical for the onboard electronics to function properly while cranking the engine. It shows the battery voltage dropped to 9.27 volts. That's OK. This isn't the same type of voltage drop as described when check the battery cables. This is a battery test and you should test yours the same, if the cables aren't found to be the problem.
Do you maintain your battery with a battery tender ? My battery cables were loose from day one. If the tech who prepped the bike isn't paying attention to this, you'll have nightmares until it corrected