Hoping for some good advice. I got a few vintage bikes with threaded forks. I actively ride them. I'm trying to find a good setup in the cockpit for ultra long distance so am buying a couple different hb, brake lever, aero bar setups cheap off ebay. I'm guessing a clamp type stem would make swapping different setups easier. Any one had experience or thoughts on this? What's a good adapter. The ones I see are 2 bolt clamp, is that enough? I'd hate to have it slip. This will be alloy. Either or both 26mm and 31.5 (?).

Thanks
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PS - I just saw a discussion from 2009 stating this is a reasonable option, and I see the gear available - Anyone have any pros/cons they care to share? Thanks

I have a threadless adaptet from VeloOrange and one from Soma.

There are dozens of brands available of varying finish quality and color.

They are all just 1 bolt for the wedge and you then use whatever threadless stem you want.
Pretty simple and straightforward tool.

I use a few of them. Along with the threadless stem they give me a much more upright position.

Some don’t have much extension on them though.

Semi-off-topic but I have a threaded fork and want to run a threadless stem also, but it's on a frame I haven't built up yet. therefor I'm wondering if it would be possible to use a 1" threadless headset and just clamp the stem around the section of steerer that has threads cut into it? Seem like this would give a cleaner look than an adapter, would likely mar the threads but I don't mind that (I doubt i'd go back to a quill, and I could always chase the threads out anyway).

I wouldn't recommend it, the tubing is thinner where the threads are cut and many threaded forks also have a groove or slot machined in them at the threads to keep the headset washer from turning or for cable stops that fit over the steerer tube from turning. Either get a new fork or use an adapter if you're set on threadless.

Thanks guys - pretty much gives me the info I needed - I'll go ahead with my projectds then.
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This may be another option... Use 1 - 1 1/8 using a spacer... Will give you more strength at the threads if you are worried.

Using Profile adapters for a couple of applications

Yes - a lot of people cringe when they see this setup on a Derosa, --- but the big 31.8 Salsa Bell Lap bars and Thomson MTB'ish looking stem make for a rock solid handling platform, --- it instantly made the front end feel more precise




--- I'm salivating here --- The Thomson/Salsa setup will never be as pretty as this Nitto/Soma ensemble though, but i'm good with that for the performance improvement

As well, a Japanese cockpit is not really traditional on a Italian bike either, especially when Campy equipped, -- but I am most comfortable on 46 bars, and soma makes a great short and shallow version



Track bike ---- profile adapter , and again with wide 46c bars, this time 3T --- not traditional or any good for a track sprint, ---- but I was just putting in laps and wanted to be comfortable

-- On this one, I threw some silver spacers under the stem to make the adapter look less odd




Gratuitous pics of dogs --- because I'm away from home for work and they make me happy

Yeah but he replaced the original fork with one with a longer steerer tube. The original threaded fork won't have enough tube exposed to clamp a stem to safely on top of everything else so he's still looking at a different fork to pull that off.

Good idea re: flexibility to re-size, and they look good on some bikes that have larger tubing.

I have one if you want it. You'd have to pay shipping.

I also have a box of stems, ranging from 26.0 clamp to 31.8, none of which I want. I can send them as well.

Spacers on the outside aren't going to make the threads on the steerer stronger.

Don't clamp anything to the threaded part of a steerer tube.

Well that is just a non sense response... Of course more material around the outside, in this case 1/8" more metal are going to take some of the pressure off the steerer tube.

Nice debate.

1-I have seen a 1" threaded fork used with a 1" threadless headset. The owner replaced the threaded-type headset with a 1" threadless headset. He gained just enough steerer length (in reduced stack height) to clamp on a stem, and cut off a quill stem bolt to use in the steerer (cleaned up the threads after cutting it off). He found an older 1" clamp stem; used it "slammed." My guess is that he's probably still got 1cm or so "space" under that stem cap. His only flexibility on sizing would be stem choice. I reminded him to re-tighten the stem on occasion, as I felt the clamping would eventually crush the threads a bit. Haven't seen him since, but I'm pretty sure he's still riding the bike (Kestrel 200SCi) I haven't heard that he's pranged the bike and broken himself or anything else. This is not my recommendation, I just saw it done. It's a cajone-driven approach.

1a-Move the approach above to 1.125" and let the shim give you the height you need to clamp on a stem. I've not seen it done, but I can see the logic in it. I'd guess the shim will give a less positive grip on those threads, though, as the shim is not designed to reduce circumference on tightening, like the stem clamp is. I'd probably cut a slot in the shim, were I to attempt such a thing. I'd let my brother test ride it first.

2-I have seen a 1" threaded fork swapped out for a Ritchey 1" threadless fork, headset swap, of course, and it worked very well. He had to use a 1 to 1 1/8 shim, as he wanted a more modern stem. The bike rides orgasmically. (Another Kestrel 200SCi)

3-I've seen many applications of the quill stem adapter. The older ones have a 1" steerer, the newer ones are almost all 1.125" They look "ok" and work fine. It's subjective, appearance, wise. At NAHBS for several years, the builders used threadless forks on finely-made steel lugged frames. I was not a fan of the look, but function over form, as it was.

Anything can be done, tried, and many things work to different levels of success. Ignorance is bliss. I somewhat agree with Kontact, in principle I'd refrain from clamping directly to the threads of a 1" threaded steerer, but I've seen it work, so go figure. If I were to rescue another Kestrel 200SCi from a landfill, I'd consider the options above, but try to figure out some way to test it. I probably would not try it on something like a Y-Foil.

A local bike shop near me still says you can't upgrade any 7-sp or less frame to 8/9/10, while my '89 Centurion is running DA9000.

There isn't more material around the outside all the way over the entire threaded section. As the steerer flexes between the stem/shim and the spacer or top of the headset, what is flexing is threaded.

This is like taking a threadless fork and scoring it all the way around just above the head set. It is incredibly stupid.



You aren't even supposed to clamp a quill stem into the threaded part of the fork - the wedge needs to be below the level of the threads for exactly the same reason - the threaded section can't take clamping forces.


The idiot in the video you posted is headed towards a deadly crash when his steerer snaps just above the headset at the thinnest spot of one of the threads. How well it is clamped above that isn't going to matter because that isn't going to prevent cracking between the stem and headset. It will look just like this aluminum steerer:




And this is what it looks like when you tighten a quill into the threaded section. Not strong enough for clamping:

Great info and pics ! RobbieTunes - what do you have for parts?
Thx
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I too would never use a threaded fork for this purpose. First of all I would never f*** with anything having to do with steering the bike. I check stem clamp bolt torque every week and definitely before any event. Remember that while there might be enough material in a threaded fork to handle the stresses, it is never tested for that scenario. There are very different loads on a fork stem between threaded and threadless.

I wouldn't even go that far. No one has ever made a steel threadless steerer with walls as thin as where the threads are cut into a threaded steerer. If it was "enough material" that's the amount they would use. It is not.

one approach , steel-tube stem raiser, a quill at the bottom , wedge bolt comes up half-way ,

where the tube of 4130 steel increases in diameter, so on top you could transfer the original stem and insert it in there..

Because bottom OD is same as top ID, so as a result its upper OD is like the fork's OD 1"

there are abundant shims from 1" to 1.125", often comes with the stem.. to use on 1" forks..


#14, it would appear, the stem was pulled up a bit much and wedge overtightened..

BTW you can find some pretty tall quill stems with angle adjustment and oprn face.. if that is your primary need, bar swapping.





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