It's not Sydenham. Sydenham was run once - in the 1135 era. Robert rode the plastic in F1 and probably an 1135 in prod.
Looking at that pic, didn't they run the Kat in both F1 and prod - and change the pipe between races ?
That's got a 4:1 on it - but it looks like the mounting bolts for the stock pipes are still in place.
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