Your frame uses a 44mm head tube. This is a good thing because it allows you to use EITHER the 1 1/8” straight steer tube rigid fork supplied with the framesets listed above, OR a tapered steer tube suspension fork. “But how, dear Surly friends, is that possible?” I’ll tell you.
Cane Creek initially supplied the individual parts for making this happen, and now they actually have a complete headset (two actually) that get the job done. Here’s how they’re described.
- Cane Creek 40 ZS44/28.6 EC44/30 – This is the headset you want if you’re using a stock Surly straight steer tube fork. I’ll break it down. The 40 is the model designation. Cane Creek makes a 10 and a 110 and some others. The 40 is good solid stuff. The ZS44/28.6 is the top cap. The ZS means it’s a zero stack – or, that the bearing cup does not extend much past the top of the head tube. The 44/28 means it’s for a 44mm inner diameter head tube and a 28.6mm (1 1/8”) steer tube diameter – which is the measurement at the top of both straight and tapered steer tubes. The EC44/30 is the bottom cup. This designation means it’s an External Cup design (the bearing cup sits outside the head tube) for a 44mm head tube and a 30mm crown race seat. This is a special adapter crown race that allows the 1 1/8” steer tube fork to work with the big ol’ 44mm bearing and cup. The part number for this headset is HD2410 through our distributor and your bike shop.
- Cane Creek 40 ZS44/28.6 EC44/40 – This is the headset you want if you are going to run a tapered steer tube fork – like the Rock Shox Bluto for example on the Wednesday or Ice Cream Truck, or another tapered steer tube fork like a carbon legged thing. It is, as you will notice from the description ALMOST exactly the same as the previous headset. The only difference is that last number - 40. It means that the crown race with this headset is for the larger 1.5” (40mm race seat) crown of a tapered steer tube fork. The part number for this headset is HD2411.
- The part numbers for the crown races individually are HD7600 for using a rigid Surly 1 1/8” straight steer tube fork and HD7601 for using a tapered steer tube fork.
What it all means is that this headset will work with both setups with the proper crown race. Did you get a complete Karate Monkey Ops a few years back with the Fox suspension fork? All you’ll need is the adapter crown race (HD7600) from Cane Creek to run a rigid Surly fork. Did you get a Wednesday or Ice Cream Truck with a rigid fork and now you want to run a Bluto fork? Get the 1.5” crown race (HD7601) and you’ll be in business. Not only that, but you’ll be able to swap back and forth from springy fork to rigid with no changes to the headset – leave the appropriate crown race on the appropriate fork and they’re absolutely interchangeable.