So I bought a Falcon frame without the headset to build up with dura ace 7700, but I have an issue. The seller said the headset had a stack height of 38mm so I went with that and just bought a jis headset with the exact stack height off of eBay (rookie mistake). My first problem is that the stack height is larger than that, but I'm simply going to buy some brass 1-inch washers to fill the space; the main issue is that it doesn't have the groves for the lock washer and instead has the top section of the fork filed down (I'm a noob so I can't post any pictures yet, but it is basically a triangle with the base at the edge of the fork with the depth of the filling decreasing as you go down the fork). Therefore, can I just not use a lockring and call it a day? Thank you. And some people may be thinking, why not just get a taller headset. The issue with that is that the lock washer still won't fit and it is just cheaper to get the cool-looking brass spacers at this point.

I suppose you mean not using a lock washer? Yes, you can use normal plain washers, no problem.

You don't strictly need the keyed washers; you just need to be a little more careful when tightening the locknut so you don't change the pre-load adjustment.

I try to avoid using keyed washers on my headsets, as they tend to bung up the threads on steerer tubes.
I just always use two headset wrenches to cinch up the locknut against the top crown securely.

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the keying you found on your Falcon's steerer is one of several types employed in the industry

this is considered a flat and there are steerers which receive the flat on the front, mostly British products, steerers which receive the flat on the rear, mostly French products, and steerers which receive a rectangular slot keyway, usually on the rear but occasionally on the front of the steerer

Weinmann, for example, offered their front brake hangers for their centrepull brakes with flats on the front, flats on the rear, a tooth on the rear and a tooth on the front


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