Kaweco AC Sport Fountain Pen Review

Kaweco AC Sport

The Sport is easily Kaweco’s most famous model.  Its ability to expand into a full sized pen is very appealing and as such I have been using one for several years now and I love it.

The AC Sport is one of the higher end models, featuring a gorgeous aluminum and carbon fiber body.  Can the AC Sport really be worth five times the price of the standard Sport? Let’s find out.


Kaweco was kind enough to send me several pens to review and the AC Sport immediately caught my eye.  The red aluminum against the black carbon fiber is striking.  I would have never picked this color combo but it’s fabulous.

The Kaweco Sport has a unique pocket friendly design.  The cap is disproportionately large and because it is faceted it won’t roll off the desk.  The small silver nib fits this pen well and the black Kaweco logo on the top of the cap is a nice touch.   The carbon inside the facets though doesn’t look as clean as it could (more on this below).  On the surface the AC Sport is beautiful pen.


Kaweco AC Sport

Score: 4/5

Build Quality

Most Kaweco new nibs require a bit of breaking in, and after a lot of use and cleaning, I finally gave up and examined the nib under a loupe.  I found that the AC’s double broad nib has a misshapen point that has been causing the pen to skip on upstrokes.

This is something that can be fixed by a nibmeister but in all honestly, I would have a hard time shelling out the dough to fix a cheap steel Bock nib.  Bad nib? Check, now on the body.

It should certainly be noted that carbon fiber is an expensive and difficult material to work with, that said, I found some issues with the carbon that sits in facets of the AC.  Some of the carbon pieces did not fit perfectly into their slots and I also noticed that all of the carbon pieces on the cap has some rough almost frayed edges (see below).

Kaweco AC Sport
If you look closely you will see that the edges of the carbon fiver looks fuzzy.

The fit and finish of the rest of the pen is good.  It is worth mentioning that with use the red aluminum will scratch.

After about a weeks worth of use I noticed that the thread has scratched.  Not a big deal but you need to be careful if you want to keep the finish perfect.
After about a weeks worth of use I noticed that the threading had scratched. Not a big deal but you need to be careful if you want to keep the finish perfect.

The black Kaweco logo on the cap isn’t the most defined and that made it a bit tricky to photograph.

Kaweco AC Sport

The issues with the carbon are minor and forgivable for a $120 pen but for me a misshapen nib is not.  This is not a cheap pen and there really should be more quality control.  I flushed the pen before I used it and the water came out completely clear, normally I would expect to see a bit of ink; this is a likely indication that the pen was not tested before leaving Kaweco.

Score: 2/5

Size & Weight

The Sport’s most prominent feature is its ability to transform from a mere 4.1” capped to 5.3” posted.  The AC Sport weighs in at 22.5 grams and the standard plastic bodied Sport weighs less the half of that at 10.5 grams.  The AC Sport is by no means a heavy pen but it does have enough weight to feel solid in hand.

My hands are on the smaller size and I find that I can use the pen unposted without any issue though people with larger hands will definitely need to use the cap as the body measures  only 4”.

The small grip section is made from aluminum and has a medium sized diameter of about 0.6”.  It feels a bit constrained, as there are not a lot of choices in where you can place your fingers.

I find the AC Sport to be fairly comfortable for long writing session but those with bigger hands may not.

Score: 3/5


Kaweco AC Sport

The nib being a double broad is buttery smooth; it feels wonderful on paper but unfortunately due to the misshapen nib it doesn’t work all that well.  The nib regularly skips on upstrokes.


Kaweco AC Sport

I also had issues with ink flow.  I normally store my fountain pens nib up but for this AC Sport I found that it can take a while to get the ink flowing properly; I was able to solve this problem for the most part by storing the pen nib down.

Kaweco AC Sport
Notice the skipping in the figure 8s at the bottom.

Score: 1/5

Filling System

We have arrived at the major downside of the Sport’s size, its filling system.  Because the body is so short this pen only accepts short international cartridges.  A converter is too long to fit.

On the plus side, the Sport accepts a standard sized cartridge which will give you lots of choice when it comes to ink, but if you love bottled ink like me, you may find your self needing a syringe to fill empty cartridges with your favorite ink.

Score: 2/5


Considering that this pen uses the exact same Bock nib as you get on the standard $23 Sport, it is hard to argue that the AC Sport is a good value at $123.   For the same sort money you could have the Pilot Vanishing Point with an 18k gold nib or the excellent Pelikan M205.

Would I recommend the AC Sport? Nope…but in the spirit of full disclosure, the moment I saw the AC in person, I knew wanted it for my collection; it really looks that good.  If the nib wasn’t such a disappointment, I would have gladly paid the full $123 for this pen.

Score: 2/5

Bottom Line: This fantastic looking pocket pen is ultimately let down by its high price and poor quality control.

Final Score 14/30

Please note: this product was provided to me at no charge by Kaweco for review purposes.

Here are some great reviews of the Kaweco AC Sport:

(I have no affiliation with the sites linked below)

Gourmet Pens –  Review: @Kaweco AC Sport Carbon Black Body Fountain Pen – Double Broad @JetPens

The Pencil Case Blog – Kaweco AC Sport fountain pen review