Condensed answer: Quill stems aren’t inherently bad and have proven themselves over the years.
However, they require a heavier steerer and a more finicky headset.
They also limit the number of forks that you can use and create a necessity to sell forks of different sizes.
How Does a Quill Stem Work
Quill stems are secured to the steerer tube of the fork via a wedge mechanism.
When you tighten the stem’s bolt, it pulls the expander/plug/wedge upward.
Since the expander and the stem’s tube have a 45-degree cut, the expander moves to the side and wedges the entire stem into the steerer tube.
The photo below illustrates the principle more vividly.
The Benefits Of a Quill Stem
1. Low price
You can find a generic quill stem for a few bucks at most bike shops.
(Obviously, this point doesn’t apply to exotic quill stems.)
2. Traditional look
Some cycling enthusiasts consider modern threadless/ahead stems a bit of a rude accessory that doesn’t match the shine of a lugged steel frame.
In different, quill stems have a soft vintage silhouette complimenting retro bicycles.
Hence why companies continue to produce various quill stem models even though the industry has already switched to threadless stems and headsets.
3. Height Adjustability
Quill stems allow you to quickly adjust their height via an Allen key. This is the strongest technical advantage of quill stems over threadless models.
If you have a threadless set-up, you will have to purchase a new stem and/or bars to increase the height of your handlebars.
This characteristic makes quill stems a popular choice for urban utility bicycles.
The producers of such bikes know that their potential clients may need a stem adjustment. And the simplest way to satisfy that requirement is to equip the bikes with a quill stem.
4. No Spacers
If you want to keep a threadless stem high, you will have to put lots of spacers between the stem and the head tube. The result isn’t always aesthetically pleasing.
Meanwhile, quill stems do not require headset spacers when you elevate them.
5. Better “Flow”
The main reason why quill stems are more aesthetically pleasing, especially when installed on a classic steel bike, is that they’re slimmer and have a better flow (the stem is one piece).
Conversely, threadless stems are bolted/clamped to the steerer and “interrupt” the lines of the bike.
The Downsides Of a Quill Stem
1. Extra Weight
Quill stems are notably heavier than a threadless set-up unless you purchase high-end components.
The reasons for the additional weight are:
To offer adjustability and reach deep into the steerer, quill stems have a long body.
- More Parts
Quill stems come with extra parts (a lengthy bolt and an expander) which contribute to the final weight of the product.
- Heavier steerer
Threaded headsets require a threaded fork with a stronger and thicker steerer.
Otherwise, the threads and the steerer’s walls won’t hold up.
For that reason, aluminum threaded forks come with a beefy steerer made of steel and aluminum legs/blades.
Carbon isn’t a good choice for a threaded steerer either due to the material’s properties. There are threaded forks with carbon legs, but their steerer is still built out of steel.
Ultimately, a threadless set-up can easily make the front end 300-400+ grams lighter – a lot of weight in the world of cycling.
2. Lack of options
The industry has already made the switch to threadless headsets and stems.
As a consequence, the market offers a greater variety of threadless stems at an affordable price. You can get a very good stem made of strong alloy for USD 10-20.
The smaller market share of quill stems is limited to utility bikes and retro machines. This reduces the manufacturers’ incentive to produce newer and more interesting models.
Switching from a threaded set-up to a threadless one will increase your stem options exponentially.
This is the main motive for the existence of quill to threadless stem adapters.
3. Forks of Different Size
Threaded forks have to come in different sizes. This is the only way to ensure a proper position of the thread for various frames.
This peculiarity complicates the manufacturing process and increases the number of forks that a shop has to store and distribute.
Threadless set-ups eliminate this problem and allow manufacturers to sell one fork size.
Threadless forks come with an extra-long steerer that the user has to cut according to their needs.
This greatly simplifies the production process and improves the compatibility of the components.
4. Extra Tools
If you want to tighten a threaded headset, you will need a set of cone wrenches. This increases the number of tools that you have to carry with you on long trips.
Meanwhile, a threadless headset can be “packed” and “unpacked” with Allen keys that all bike multi-tools have.
5. No Faceplate
The vast majority of quill stems do not have faceplates. To replace the handlebars, you will have to remove the grips/bar tape as well as the brake and shifter on one of the sides.
If you use grips that are difficult to pull out or drop bar tape, the procedure can be very slow and annoying.
Of course, there are some quill stems with a faceplate allowing you to quickly change handlebars (e.g., Velo Orange’s quill stem), but most models do not provide that option.
A neglected quill stem can result in spectacular corrosion. If all components are steel, rust is the most likely problem.
However, if there’s aluminum involved (e.g., alloy stem in a steel fork), galvanic corrosion may take place.
Galvanic corrosion is a deterioration process occurring when two dissimilar metals are in contact and the presence of a conductor like water.
In this case, the aluminum stem would be giving up electrons even though by itself it’s more corrosion resistant than steel.
However, this is a custom scenario known as preferential corrosion.
Unfortunately, galvanic corrosion could make it very difficult to remove the stem.
The only way to prevent galvanic corrosion would be to avoid using dissimilar metals or to service the parts frequently.
Periodically putting a layer of grease on the involved components should be enough to circumvent this problem.
In different, a threadless stem is a lot less likely to create similar issues.
Are Quill Stems Safe?
Many wrongfully believe that quill stems are weak and dangerous. This isn’t really the case. A quality quill stem in good condition is very strong and can handle a lot of abuse.
Before the suspension fork revolution, quill stems were found on mountain bikes which at the time had rigid forks.
The stems were holding up just fine even though there was no suspension to smoothen the ride.
Obviously, everything can break in certain situations, but in general, a good quill stem is very reliable.
That said, one has to examine the steerer too. If it’s thin and poorly made, it may end-up snapping because quill stems place a lot of stress on the component.
If the steerer is thick enough and made of steel, then it should hold up just fine.
Note: If you’re purchasing an old bike, and it comes with a quill stem that worries you, it will be helpful to service the stem and headset and examine them in the process. If you see cracks or suspicious signs, replace the affected parts.
The most important question is whether the components are built to the necessary standard and match. If those two conditions are met, the rest comes down to personal preferences.
There’s isn’t a law stating that you can’t put a quill stem on a new bike.
Ultimately, it’s your bike, and you can do whatever you want with it.
The wedge of my quill stem is stuck. What should I do?
If you turn the bike upside down, you will see the wedge through the bottom hole of the fork.
You can thread a long bolt through the wedge (maybe one from an older quill stem) and then hammer the head of the bolt with a mallet. If everything goes well, the wedge will come out from the top.
If you don’t have a bolt, you can use a dowel that would fit.
Note: If the wedge isn’t stuck badly, you could try a less aggressive approach:
1. Untighten the stem bolt until part of it shows on top.
2. Hammer the bolt down.
Mechanics often use this method to free a seized quill stem.
Don’t use excessive force. A medium level of effort should do it.
For better results, lubricate the area with penetrating oil.