Bicycle Mechanics - Threaded fork with threadless headset/stem?

I have a co-worker that wants to start riding to work but his front suspension fork is toast. His bike is set up with a 1" threadless headset/fork/stem. I have several 1" threaded forks kicking around, would it be possible to use a threaded fork with his existing headset and stem? I can always swap out the headset and stem if I have to but I'm looking for the easiest and cheapest way to get him started.

No, the steerer tubes are probably not long enough. If they are, then maybe.

No, the steerer tubes are probably not long enough. If they are, then maybe.

His bike is on the small side and I have a fork from a very large bike, so I'm thinking I can swing it if that's the only hang up.

Some of the more technical folks in here should be able to tell you if the steerer is stable enough to deal with the stresses that come with having threadless stem attached to it. Hardness of the metal or the presence of the threads may be an issue. I wouldn't feel all that comfy with it if I was riding off road or other such stressful riding.

I've done it. The only real difference is the threads. I took an adjusting cone from a threaded steerer and burred out the threads with a Dremel until it would just slide over the steer tube. It looks a bit odd, but it works.

I've done it. The only real difference is the threads. I took an adjusting cone from a threaded steerer and burred out the threads with a Dremel until it would just slide over the steer tube. It looks a bit odd, but it works.
I don't think he'll need to do that here since he's working with threadless headset. He should be able to slide the top bearing race (cone) right on.

so far as my LBS tells me a star nut and maybe a quill will be needed... beyond that yes it will work... otherwise if the steerer is long enough... slap a star nut in and put your stem / bars on.

Sweet, I forgot I started this thread. Thanks everyone, I guess I'll give it a try!

His bike is on the small side and I have a fork from a very large bike, so I'm thinking I can swing it if that's the only hang up.

The people who make and sell forks say not to do it. They say that clamping onto the threaded portion of the steerer tube will create a stress rider at the bottom thread and can snap off.

That's correct. But what is their stock & trade again?


Right.


Think there might be a vested interest?

I don't know if you want to put a fork designed for a larger bike on a smaller bike. I may be totally wrong, but won't the handling be funny?

No, the only difference is the steer tube length. That's an interesting point about the extra stress on the bottom thread. I wonder if this actually happens. I found a bike at the dump with a 1" threadless fork though, so the question may not need an answer in this case. It's a suspension fork and I know he would prefer a rigid one, but we'll see what he says.

That's correct. But what is their stock & trade again?


Right.


Think there might be a vested interest?

I sure hope that you signed your organ donor card.