If you have retired gear in Strava and it is not shown in StatsHunters you can solve this with a the following actions:

1. Open the gear settings page https://www.strava.com/settings/gear
2. Temporary unretire the gear that is missing in StatsHunters
3. Logout and re-login to StatsHunters (the unretired gear is now added to StatsHunters)
4. Retire your gear on Strava

The retired gear should now be/stay available in StatsHunters for filtering.