So I took one final day off before pushing ahead full steam to get home. Among other endeavors, I cleaned and tuned up my bike. After a thorough inspection, I’ve found a few odd cracks in my RIM. Back rim. One side has several cracks near the spoke on about a third of the spokes. Not sure how. Spokes too tight? Tires too inflated? Just a lot of bumps and a lot of weight over a couple thousand miles? Defective rim? Not sure but I’m pushing on, hoping to get home before anything further comes about.
This is where u can help. Apparently I have quite a readership, which is great, so maybe some of you can get active and give me some advice. I’ve included a photo below. Look at the white cracked area just above the spoke. If you have any idea or experience what may cause this, how much worse it can get, and-most importantly-if I need to be concerned over the next eight days about this, please comment here or email me. Much appreciated.
Hoping for a Tail Wind 
Hey Tony –
Good luck continuing your ride on the trashed rim. It may fall apart before you get home; just keep a close eye on it for advancing cracking. If it does fall apart while you ride, it is your rear wheel and may not cause you to crash like the failure of the front wheel will. This kind of damage is caused by overloading the rim. The spokes may have been tensioned too much; but more likely, your miles of riding with the weight of your packs caused the failure. I assume you got the wheels with the complete bike. Often designers of complete bikes cut corners here and there and often rims are not of the highest quality. Your wheels may also be laced with straight gauge spokes; butted spokes absorb and dissipate the forces better. The wheel the bike came with may be sufficient for general riding and light touring; your tour, with more than 100 pounds of gear over three thousand miles is extreme and calls for the best equipment to withstand the insults to the bike. When you replace the wheel, make sure you get a wheel with at least 36 (40 would be better; 48 bomb proof) butted spokes. Hand built by a wheel builder will also help. Bike All Paths, John Mcc
Good luck continuing your ride on the trashed rim. It may fall apart before you get home; just keep a close eye on it for advancing cracking. If it does fall apart while you ride, it is your rear wheel and may not cause you to crash like the failure of the front wheel will. This kind of damage is caused by overloading the rim. The spokes may have been tensioned too much; but more likely, your miles of riding with the weight of your packs caused the failure. I assume you got the wheels with the complete bike. Often designers of complete bikes cut corners here and there and often rims are not of the highest quality. Your wheels may also be laced with straight gauge spokes; butted spokes absorb and dissipate the forces better. The wheel the bike came with may be sufficient for general riding and light touring; your tour, with more than 100 pounds of gear over three thousand miles is extreme and calls for the best equipment to withstand the insults to the bike. When you replace the wheel, make sure you get a wheel with at least 36 (40 would be better; 48 bomb proof) butted spokes. Hand built by a wheel builder will also help. Bike All Paths, John Mcc