How'd they get in to the garage?
I've gotten a few stolen bikes back. Thieves will have to expose themselves to sell the bike, stay vigilant keep looking it's out there. I recovered one of my stolen bikes from a homeless camp, couple others were on Craigslist.
Make sure to make a police report. You'll need it for leverage to get the bike back.
When confronted thieves will say "didn't know it was stolen" to avoid arrest. If you've got the burglary report with the bike listed you can quickly skip over this excuse and go straight to informing them it was stolen and then getting them arrested.
Call perps on a Friday after payday and keep the topic on giving them cash. Meet in a safe place, and call the cops on the way to the meeting.
No need to threaten them, pay anything, or any other excitement. Just be polite, keep them talking till the cops show.