The extra cowling is the single speed conversion kit - it has two raised bits of cowling on either side of the cog, I guess to stop the chain derailing. Popped the post out and the diameter is 26.4.
@kimchi started
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The extra cowling is the single speed conversion kit - it has two raised bits of cowling on either side of the cog, I guess to stop the chain derailing. Popped the post out and the diameter is 26.4.