Based on what I've read on this site, it's better to bring bikes than to buy them on island (we will be leaving them on Bonaire). I can't figure out if KLM will let me consider them luggage or if I'll be charged separately for them regardless (80 Euro per bike one way).

Anyone know if they can be considered luggage rather than bikes?

If anyone has anything in writing on this, please let me know so I can show it to the person at check-in.

Thanks

Forget the question. I figured it out. The KLM page with this info on it has some HTML that's not working properly so I couldn't access it. But when I googled it, the page came up properly.
To answer my own question. It's 80 Euros per bike regardless of other luggage. Sometimes bikes can be considered checked luggage (no extra fee) but not on this particular flight.
I am still wondering how much a bike costs locally...

You could find out local bike prices from De Freewieler in Kaya Grandi - email them on freewieler@flamingotv.net

Bike rentals are also available at Bonaire Dive and Adventure. I think $15/day. Best to reserve ahead if size is an issue. They rent Trek Navigators. I own one and it's a fun bike for the Bonaire terrain. They will also take orders for Trek bike at full retail price that you would pay at a US bike shop. Hope this helps. Candace Platz