Fountain Pen Review: Opus 88 Koloro Blue Blue

I was curious about the Opus 88 Koloro fountain pen ($93) which combine ebonite body components with transparent resin as well as being eyedropper fillers. This combination of elements seemed very unusual in a streamlined design I found aesthetically appealing so I was willing to give it a try.

The pens ship in a fairly simple package with a cardboard shipping sleeve and a magnetic closure box containing the pen and a rubber eyedropper.

I ended up filling the pen using my regular syringe rather than the eyedropper included as I felt I could better control it and get around the plunger mechanism. I made sure to watch the video posted by Pen Chalet about how filling mechanism works and how to loosen the piston before using the pen to aid in ink flow. I’ve never used an eyedropper that required this so I’m glad I watched the video.

The nib looks to be a standard German nib unit with the Opus 88 branding added.

The cap can be posted and it looks pretty streamlined but it makes the pen pretty back heavy. Uncapped, the Koloro is 5″ long. Capped it measures 5.5″ and posted it measures a whopping 6.25″.

I worked with the pen over several days and it was definitely hard starting after sitting and required priming the feed by twisting the piston out a turn and then turning it back in and then out again a couple times to get ink flowing again. At least, that was my experience. While this was not the exact advice from Ron, it was the quickest way I found to get the ink going again.

Once the ink was flowing, the pen writes beautifully. The weight in the hand is nice and the grip and threads transition nicely so its easy to write with it for longer periods. I prefer using it unposted.

The combination of ebonite and translucent sections is really mesmerizing. I do wish that the ebonite has included an ebonite feed which I think would have helped with the ink flow.

I do like the beaded detailing around the clip as well.

The two clear sections on the pen align with where the nib section is and where the ink is so you can see the nib and your ink capacity which is both aesthetically appealing and functional. I tried to put somewhat coordinating ink in the pen using Monteverde California Teal (review coming soon). I wondered if a more lubricated ink might have also helped with overall ink flow.

For size comparison, from left to right: Kaweco Sport, Pelikan M605, Sailor 1911 Regular, Lamy AL-Star, Opus 88 Koloro, Pilot Custom 912, Karas Pen Co. Decograph and TWSBI 580.

The same pens listed above, posted.

The Koloro weighs 25gms capped and 15gms uncapped, filled with ink. The weights listed above are all for pens capped or posted so the Koloro is pretty consistent with many of the pens of similar size.

Overall, I find the combination of materials interesting and was intrigued by the filling mechanism but I am finding some issues with the tendency to need to prime it. I’m not sure how effective the Koloro would be as an everyday writer for meetings and being used on and off through out the course of a day. That is a test I did not get to put it through yet. But just in my weekend writing tests between one day and the next and needing a good while to prime it means this may be better suited to use for letter writing, journal writing or other longer writing sessions where you can sit and prime the pen prior to use.

There’s something about it, in its aesthetics that appeals to me, so I want to find a way to make it work for me. Does that ever happen to you? Beyond rational though, you like a pen despite its flaws?

DISCLAIMER: This item was sent to me free of charge by Pen Chalet for the purpose of review. Please see the About page for more details.

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12 comments / Add your comment below

  1. Thanks for the review Ana. I have the yellow version with a fine nib and it’s my first eyedropper pen. I am really enjoying how well it writes. It is very comfortable in the hand. I hope you can get your pen to write better.

  2. Although my experience is limited I have to say that I am fairly intolerant of flawed items (pens just being one of them). I got a Pelikan m205 blue demstrator that really looks cool but the nib is so scratchy I hate writing with it. I tried some self servicing with modest results but finally broke down and bought a new nib. I also had a beautiful FC ambition in Black that wrote beautifully but the converter always got stuck in the barrel. Sent it back. So yeah, flaws ruin the love.

  3. My experience with this pen makes me think that if you leave the shut off open while you carry the pen it will dry out, but if you close the shut off if writes as soon as you uncap it. I think the explanation may be that if the shut off is open the ink drains back into the barrel from the nib and feed. But if you close it, the ink that was in the feed stays there and stays wet.

  4. Hi Ana, thanks for the review…

    I watched the Pen Chalet video (direct link at the bottom of this comment), but in my opinion it it explains next to nothing about the “piston”. Why is this pen sold as an eyedropper-filler when it has a piston?? Or maybe it’s not a piston mechanism at all, but instead it is an ink shutoff valve? The Pen Chalet site says: “It also has a small piston or shaft that allows you to burp the pen if you need to…” What the heck is that all about? In my book, if you have to force-feed ink in order to get a pen to write, then that pen is BROKEN. Pen Chalet also says: “You can release the back-end of the pen and that allows air to flow through.” I can see this being necessary with a badly designed large capacity eyedropper-filler, but why didn’t they just add a breather tube instead? This also hints that the “piston” is really just a valve.

    OK, this video shows a bit more about this pen:

    From the video (link above) it looks like the “piston” is really a screw-down shutoff valve. To avoid flow problems with this pen, it seems to me that you MUST unscrew the finial knob a few turns to allow air to flow into the barrel and to open the valve sealing off the feed. You can still post the cap with the knob loosened and no, the cap does not post to the knob (you see that TWSBI?) To avoid an inky mess, don’t forget to screw the knob back down when you are done using the pen! And use common sense when opening the valve on an airplane! The video also shows an instruction pamphlet that comes with the pen that probably explains a lot. But alas, no reviewer or reseller has seen fit to post a copy of the pamphlet so-far.

    The video (link above) shows the pen takes a German Knox #5 (5mm dia. feed) friction-fit replacement nib. Pen Chalet carries Knox replacement nibs, but unfortunately only in the #6 size. Knox #5 nibs are generally harder to find compared to the #6 size. Or you might just try sliding in some other #5 nib from the likes of Bock, Jowo, Nemosyne, etc. The Birmingham Pen Co. in Pittsburgh, PA carries Knox nibs and they do currently have some #5 nibs in stock:

    Then there are the aesthetic issues I’m having with this pen: 1. The #5 nib looks way too small for the rest of the pen. 2. I wish they had used Ebonite for the section instead of of just extending the acrylic plastic used for the barrel. 3. It is clear from reviews that this pen is unbalanced when posted. (What is it with Chinese/Taiwanese pen makers and top-heavy pens?)

    On the plus side the build quality looks good, and the price isn’t too bad.

    Missing Links:

    Here’s the link to the manufacturer’s Web site. It has a few pictures of some interesting pen designs, but nothing else. Strange:

    Here’s a direct link to the Pen Chalet video on YouTube. Take a look at their other YouTube videos while you are there:

  5. That is frustrating. I have ordered one of these pens, the tan/blue, and I hope it behaves better. I have made note of Ted’s comments about the shut-off mechanism; hopefully that will help.

    I, too, have often had a pen that I just loved, based on the color, design, how it fit my hand, etc. It can all come crashing down based on a bad performance. Basically, anything that affects how well it writes messes with me. And that includes bad flow, scratchy nib, skippy nib, dripping, anything that has to do with the performance of the pen. Because that’s the heart and soul of the pen – the nib, how it writes, and how the pen performs. If I have a pen I just love for other reasons, but there’s something wrong with the performance, I have found that I will go to fairly extreme lengths to fix it so that it becomes a good, dependable writer. I think that’s part of my addiction. 🙂

    1. Interestingly, I pulled it out at pen club yesterday and, without priming it at all, it wrote with no trouble after sitting for a couple days so maybe it’s magically sorted itself out? Sometimes, patience is also a virtue too.

    2. An update: I received my tan/blue Koloro. The first time I wrote with it, it seemed a little dry. Didn’t write very well; it was almost a little scratchy. I let it sit in a pen cup, nib down, for a few days. Today I tried it, and it wrote much better. It still went dry and had hard starts after holding it open for a very short time. However, when I didn’t do that, and just wrote continuously, it was wet enough and wrote very nicely. My M point writes like a F. But it’s smooth and actually has a pretty nice little feedback; it feels good on the paper. All in all, given the unique design of the pen, I’m glad I bought it. When I find a pen model I really like, I often buy it in another color. I don’t think I’d do that with the Koloro, though. I don’t like it THAT much. But I’m happy with the one I got.

      1. I’m glad its working better for you but sad to hear its a bit scratchy. I’ve left mine sit horizontally for about a week and, while I may need to prime a few strokes, its writing much more consistently now that I’ve had it inked up for a couple weeks. I’m pretty happy with it and having it on the table, my husband has started picking it up regularly too. He is enjoying the size and shape of it. The feed system is a little unusual but I love the overall size and shape so maybe they will readdress the filling system a bit. I’ve never had quite so much trouble with an eyedropper pen before.

  6. After the review and watching the more “extended” video I broke down and purchased one. I could not resist and the “technology” is different from others that I have, plus I needed an excuse to get another pen:-)

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