How early is too early for check-in?

Basically, I have an upcoming itin. BOS-MAD-JNB (all on IB metal -- the "Other European Airline" forum is not that active, and since IB is a oneworld member, I figured this forum is my best bet for an informed response). The itin. was booked as a multi-city ticket.

The stop in MAD is a 2 day layover. I'd rather not have to carry my golf clubs and summer clothes to/from airport/hotel in MAD. Can I check them straight thru in Boston? What about checking them in upon arrival in MAD? If so, I realize the risks associated with such a move -- the clubs may never show up in JNB!! But I'd love to hear what others have to say on this.

Any thoughts would be greatly appreciated.

Cheers.

The airline will most likely not accept a through check-in of your belongings while you take a stopover. However, as a close second, you should check if MAD has any left -luggage facility at the airport. Many airports do, there is a modest charge but well worth the convenience.

I see that you're AA Plat, which means you'll have access to OW Lounges.

Not sure if this will work, but you could potentially see if you could leave your bags with an IB Lounge. (They have a few lounges in Term 4 at MAD.)

I've left my bags in a lounge before during stopovers, but I was also doing it as an AC member in a domestic AC...YMMV with partner lounges.

You left the bags there for two days? Even if they would allow it, I'm not sure I would do that. I'd suggest Left Luggage. Sure you'll pay for it, but it's likely in a locker rather than out in the open.

Cheers.

Sorry I wasn't clear. I've left bags in an AC for a "short" stopovers before (6 hours) - not for a few days, though. I never leave my bags in the open in one of those "luggage storage" areas. I always have my bags locked in one of the back offices that the AAngels use.

2 days is most unlikely to be allowed - airports generally have rules on maximum time bags can be stored in transit

There's a left luggage facility in T4. I'd leave your gear there.

Awesome. Very useful information. Found this on MAD's website:

Is there a left-luggage office at the airport?

There are three left-luggage offices at the airport: the first in T1, the second in T2 and the third in T4. All baggage left at the left-luggage office passes through an x-ray checkpoint to verify that they do not contain dangerous items or objects.

Price for locker rental: part or whole of one day*, €3.83 (large and small locker); from two to fifteen days: large locker, €4.92; small locker €3.83. Storage from day fifteen on: 1,97. Transfer to the warehouse: €39.34 Special baggage €4.78.

There are lockers specifically designed to deposit large objects such as bicycles, surfboards, etc.

To use the left-luggage office:

Request the key from the desk personnel. You must show your passport or identity card.
Get a token from the vending machine (it takes coins and notes).
Pass your baggage through the security scanner.
Open the locker by turning the key in the direction shown, put your baggage inside and close the door.
Enter the token in the slot and close with key. Keep your key, it is your evidence of deposit.
Information telephone: 902 404 704.

Information left-luggage offices 917 466 065 (T4) y 913 936 805 (T2).

* All or part of a day: 24 hours from the time the item is deposited. It is charged per periods of 24 hours.

Sorry don't know about MAD, but most domestic OW carriers won't accept bags until 4 hrs before departure time IIRC.

This is just information regarding JAL at NRT.
Suppose I fly Honolulu to Bangkok through Narita.
But stopover at Narita for 1 day and next day I fly to BKK.
I can not check in the luggage through BKK in Honolulu.
But at NRT, after I pick up the luggage, there is a desk that they can reload the luggage for next day flight in advance.
I think JAL allow this service if the connecting flight depart within 48 hours(maybe 72 hours).
I have done this so many times.

I am not sure JAL does that service if the connecting flight is not JAL.
I think NRT is the main airport for JAL and they have such facility to accomodate the luggage.

Anyone has similar experience at other airlines/airports?