I have a (older, suspension) fork with 1-1/8" threaded steerer. The steerer is 140mm from crown race seat to top and has 24mm of threads, so 116mm unthreaded portion. I want to put it on a bike with a 100mm head tube using an inexpensive threaded headset, like perhaps a Ritchey Logic. It should be fine in terms of stack height, but do I have enough threading?
Essentially I need to be sure the lower bearing plus space in the upper bearing below the adjustable nut adds up to 16mm or more. This seems likely since lower stacks seem to be ~ 12-14 mm by themselves, but I want to avoid any surprises. Obviously the right way to do this is to go measure a bunch of headsets, but not sure how much selection I'll find since 1-1/8" threaded is a dying species.
I have a (older, suspension) fork with 1-1/8" threaded steerer. The steerer is 140mm from crown race seat to top and has 24mm of threads, so 116mm unthreaded portion. I want to put it on a bike with a 100mm head tube using an inexpensive threaded headset, like perhaps a Ritchey Logic. It should be fine in terms of stack height, but do I have enough threading?
Essentially I need to be sure the lower bearing plus space in the upper bearing below the adjustable nut adds up to 16mm or more. This seems likely since lower stacks seem to be ~ 12-14 mm by themselves, but I want to avoid any surprises. Obviously the right way to do this is to go measure a bunch of headsets, but not sure how much selection I'll find since 1-1/8" threaded is a dying species.
The XT headset has a 37.5 stack height, so your right where you want to be. Even if it a little over, you can cut the steerer or add a spacer between the bearing cap and the locknut.
I have a (older, suspension) fork with 1-1/8" threaded steerer. The steerer is 140mm from crown race seat to top and has 24mm of threads, so 116mm unthreaded portion. I want to put it on a bike with a 100mm head tube using an inexpensive threaded headset, like perhaps a Ritchey Logic. It should be fine in terms of stack height, but do I have enough threading?
Quoted message said:
The XT headset has a 37.5 stack height, so your right where you want to be. Even if it a little over, you can cut the steerer or add a spacer between the bearing cap and the locknut.
Thanks, but stack height is not really what I am worried about; as you say I could always add a a spacer. With a threaded fork you have two potential problems: is the steerer long enough, and do the threads go down far enough to allow the adjustable race to reach the bearings? It's the second I was asking about.
I'm not sure Shimano make the XT headset anymore, BTW; they may still sell a cheaper model. Selection in 1-1/8" threaded seems pretty small now.
Thanks, but stack height is not really what I am worried about; as you say I could always add a a spacer. With a threaded fork you have two potential problems: is the steerer long enough, and do the threads go down far enough to allow the adjustable race to reach the bearings? It's the second I was asking about.
I should think that cutting additional threads in your existing steerer, if needed, is fairly trivial.
If you don't have enough threads, any shop can run another 1/2" or so for $5 or so.
Ignore this guy's advise. First, it's unsigned. Second it's a very bad idea to cut threads on a steerer with a die. The die is meant to clean existing threads. Cutting new threads with it will result in one or more stress risers that can cause the steerer to fracture. The original threads were rolled, not cut. Phil Brown
