Do not take a used item as a spare.
Take a new one! Not an old one, the weight difference is minimal. The difference in cost is small compared to your trip costs.
The chain is heavy. I'd not carry it! A front sprocket is much easier - smaller and lighter. And cheaper. You may find a place to bolt it to the bike - saves luggage space. You'll be fairly full 2up, don't take stuff you can get along the way.
At 10,000km look at the chain ... if wearing .. organise a new chain and sprockets for the next service. Repeat this inspection every, say, 5,000km ... as soon as you see any signs of ware .. organise a new set. It does not have to be then and there .. but at the next service point, a major town where these things should be available. Don't skimp on the replacement ... replace it all. Try to get it organised before you arrive so you are not waiting on parts.
|