Originally Posted by
ivan_yulaev
With a threaded headset, only the last ~40mm is threaded. So you need to hit that window and still have enough threads left. The formula should be something like (steerer) > (head tube + headset stack height), but only greater by about 10-20mm.
But in the OPs case it would be simpler to just measure from right under the crown race to the top of the topnut and subtract 2-3mm. But a slightly longer steerer is always better than too short.
The hard part will be finding a 1" threaded "Suspension Corrected" fork. Check Nashbar they may have one.
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