Hello experienced ones.....

Have a chain and sprockets questions or two. Hope that someone can give me some advice.

Fitted a OTR drive kit set eatlier this year. 525 size and X-ring and sprockets size 15/48. And have after that done a long overlanding tour and are going to continue soon....

Now after around + 30 k km the rear sprocket is almost done but the front sprocket looks as new, as good as no sign of wear. Isnt that a little strange?
The chain has only been adjusted 3 times during this 30 k km as it havent been neccesary to do it more often. And not much at a time either. Could the chain just be too hard on the rear sprocket? Harder material or something like that?

So its soon time to change, well at least the rear sprocket. But I suppose I should I change the chain as well. What do you guys think?
Front sprocket looks fine so I guess I dont need to change that....or?

Have got a hold of a gold O-ring 525 chain here I am now but I also carry a spare X-ring chain with me. Is there any big difference in these ones? What would you guys fit?

Thaks in advance!

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