Strava Rides
 

Does anyone know if you can upload another riders ride from Strava site to a Garmin gps?

I'm not aware of the ability to export GPS data from another user's ride on Strava. A couple of alternatives:

1) Message the other user to see if they would be willing to email a *.fit file to you (this may creep some people out though);

2) Manually replicate the Strava ride on MapMyRun then export a file from MMR and import it as a Garmin Course.

Export GPX from stava?

I think then on the Garmin 800 I just stick it in the right folder and it is imported. I think bike route toaster will import the GPX and allow you to tweak it for downloading into a garmin.