Surly 1x1 vs. Instigator V.1 Fork Long-Term Review

The Surly 1x1 and Instigator V.1 forks are excellent items for an adventure bike. They are a great way to convert old, 26er mountain bikes into heavy duty gravel grinders. However, they are extremely similar; in fact, the Surly website does not have much information about the difference between them other than the 0.1kg weight difference and a few mm difference in their axle-to-crown length. In July 2014, I was looking for a rigid fork to convert my 2002 Kona Cinder Cone into a gravel/commuter rig. After narrowing my search down to the Instigator and 1x1, I went with the 1x1 over the Instigator due to its lighter weight. I didn't really understand why they would make two, almost identical models of forks though.

The original (2014) Cinder Cone build with the 1x1 fork

Cinder Cone with 1x1 fork

Cinder Cone with 1x1 fork: tube sizes of the frame and fork look proportional

However, in May 2017, my good old Kona Cinder Cone cracked. I was about to sell off its remaining parts for a few pennies, and get a proper gravel bike of some sort. I decide to wait a month or two however, in case an opportunity pops up for a cheap replacement. I also saw that Giant Canada had its warehouse sale in a week, so I decided that might be a good place to start. I ended up scoring a Giant XTC Advanced SL 26er frame for $50 (brand new obviously)! I quickly built it up with my old parts.... After I went for my first few off-road rides, the Surly 1x1 fork felt sketchy in the frame. I had done the same ride on my old frame with no problem, but this top-of-the line frame didn't function the same way for some reason. I got sketched out after a while because I was putting the bike through some rough trail riding, and I could always see the fork flexing tons. I thoroughly inspected the fork for cracks several times, but there were none. I decided that after 3 years of heavy riding, I should just replace it anyway. 

Giant XTC with 1x1 fork

Giant XTC with 1x1 fork: fork looks flimsy next to the huge carbon frame tubes

Giant XTC with 1x1 fork: fork looks flimsy next to the huge carbon frame tubes

Giant XTC with 1x1 fork during a 200km gravel ride

Giant XTC with 1x1 fork riding Vancouver Island

I started to think that the added stiffness of the XTC frame (compared to the Cinder Cone) might be what made the 1x1 feel sketchy all of a sudden. As a result, I was back to looking at my options, and the Instigator V.1 looked promising with the extra 100g of weight, as it might contribute to added stiffness that would match that of the carbon frame. I emailed Surly to clarify the difference between the two forks, and this is what they said: "The Instigator 1.0 fork uses thicker tubing and is more heavy duty than the 1x1 fork. Instigator 1.0 fork was tested to dirt jumping/tandem standards. You’ll want to make sure the A-to-C is within your manufacturer specs. If your planning on using the fork on a gravel grinder bike, the 1x1 will weigh a little less and be plenty strong for the application. If your planning on taking the bike off some jumps, I recommend the Instigator fork."
What I would add to that is that which fork will work best also depends on what frame you're putting it into: a crazy stiff carbon frame will feel way nicer with a heavier fork, while an old, flimsy alu/steel frame will feel perfectly balanced with the 1x1.

I ended up buying the Instigator V.1 fork, and I absoluely love how the bike feels ever since. The tubing is noticeably larger, and it flexes much less under braking. I still use the fork, and it is holding up excellent (as expected). 

Giant XTC with Instigator V.1 fork: frame and fork tubes look proportional

Overall, I would highly recommend both forks. They are a great replacement for old suspension forks that don't do much due to their age and lack of maintenance, and have a severely creaking crown assembly (i.e. every suspension fork made before ~2010). I would choose between them based on application as well as frame/headtube stiffness. For a carbon frame, I would definitely use the Instigator. For a 1 1/8 headtube alu/steel frame, the Instigator would likely be too bulky, and the 1x1 is perfectly good.