Stayed at the Tango Hostel on 2014-06-20. They were reticent about accepting bikes but in the end they accept two DR650s under agreement that we moved them in the morning. It sounded like the PM staff has to beg the person on the phone. The garage mentioned in the OP is now mainly used for backpack storage and asado - a common room.

I spoke with the staff as I was told, and I paraphrase: "We welcome motorcyclist but having motorcycles is a hassle to us. They are in the way of our backpack storage and asado grill. We would rather not have them as their is cheap paid parking down the street."

In the end, the Tango Hostel's space was cramped, with people tripping over each other in the kitchen, etc. It was really a "gap year" party hostel with fairly loud music and a constant chatter until 1:30AM curfew. YMMV.

Buenos Aires
 

Would recommend Puerto Limon Hostel, happy for you to drive through reception and living-room to park in the central internal patio! It doubles as a smoking-area, although there is space for about 6 bikes, I dont know what their threshold is! Well maintained hostel and good kitchen. Decent dorms.

Puerto Limón Hostel
Chacabuco 1080,
San Telmo


I stayed in Kilca Hostel also, but wouldnt recommend it. It has a large internal patio that is adjacent to the building, which could take quite a few bikes. It is poorly maintained and quite run-down. The prices on their website are cheaper than walk-in prices, but you can ask for the internet price.

Kilca Hostel,
Mexico 1545,
Montserrat

Comodoro Rivadavia
 

Javito Hospedaje,
Sarmiento 634

The Owner Jorge loves motorcyclists and is very fun and outgoing guy. 200-250ARS per person.

Has long side garage with ramp that can hold maybe 8 bikes.

Place is basic. It has a kitchen and dining area. Wifi is limited, only available in front of building.

Salta terra oculta is no more it's become more posh the most inexpensive hostel is backpackers on Buenos Aries street between Tucuman and corrientes address is 930 Buenos Aries salt Argentina. At this time for a dorm bed 100pesos and they have parking behind a gate ..the place is a little old but bike is safe ..

If your sick of the city loki hostel salta is also a good option it's outside of town fresh air beautiful views of the mountains pool bar food etc.. this loki is much more relaxed than the other sister party hostels.. 7.50usd for a dorm bed ..plenty of parking for bikes awesome hot showers..
RN51, La Silleta, Salta, Argentina

Tilcara hostal sayana on the corner of 743 belgrano and alvarro bike or car parking across the road in a gated area I'm paying 150pesos for a room shared bathroom right next to the central park and it's on the main tourist street ..