At our recent monthly pen club in London, my latest purchase drew quite a few admiring glances. This was the Majohn P140 in a clear demonstrator version.

My own experience of this pen is still in its infancy. I first received an email from a friend overseas, on 2 April 2026, who had been down the rabbit hole of Chinese pens. One that he thought might appeal to me, was the Majohn P140 as it had a number 8 nib and an ebonite feed. I found it on Amazon and was immediately taken with the clear acrylic demonstrator version. This gives the clearest possible view of the nib and feed, the ink reservoir and the piston mechanism, which appears to be brass. I ordered one on 8 April and it arrived on 9 April, 2026.

Unboxing.

The pen comes in a smart black cardboard box, with a protective padding surround and the pen itself in a clear sleeve. Inside the box is also a “manual”, a sheet of filling instructions to cover five different filling systems with diagrams annotated in Chinese on one side and English on the other. It does not cover disassembly.

Picking the pen up for the first time, it is weightier than I expected. Its size and rounded shape give it a wonderful tactile presence. It looks and feels to be of good quality and is a pleasure to handle, even before it has seen a drop of ink.

Description.

This is a large sized, piston-filler fountain pen. The ends are rounded and being also of the same clear acrylic as the rest of the pen, they are rather nice to gaze into.

The pocket clip has no brand name and is very stiff to raise. The cap has one narrow, plain cap band one decorated broader band, but again, no brand name or model number, nor any mention of its country of origin, presumably China.

The cap unscrews in two complete rotations. It does tighten very securely. There is no inner cap but when capping the pen, it comes to rest with a visible ledge inside the cap up against the front of the grip section, which should produce a good airtight seal.

The nib, a #8 size, is impressive in itself. It is a steel nib but coated, I imagine, with a PVD plating of gold or some gold-coloured metal, matching the pocket clip and other furniture. There is a sun emblem around the breather hole. Some text on the nib reads “MAJOHN, Expedition, F” (for fine).

The grip section is very girthy, tapering slightly from around 13mm to 11mm. At the end of the section, there is a raised flange, to prevent your fingers from sliding onto the nib. This rim is a little sharp . However I am glad that a metal ring has not been added, since these can sometimes (a) trap ink after filling, which then gets on your fingers, (b) cause distracting reflections, if writing in sunlight (eg Pelikan M800) and (c) corrode.

The broad acrylic barrel shows the piston mechanism, the black rubber plunger and an ink chamber of about 29mm in length by 13mm diameter, considerably wider than a typical ink cartridge. The piston knob operates smoothly, drawing up a large volume of ink very swiftly.

Size and weight.

The pen measures around 155mm closed, 133mm open and 170mm if posted. Mine weighs around 38.5g filled, comprised as to 27.5g for the pen and 11g for the cap alone. The cap does post well, but the pen then becomes rather too long and heavy for my taste. However, as with most pens of 130mm or more uncapped length, there is no need to post the cap.

Nib and writing performance.

After flushing the pen with warm water, I filled it with Diamine’s Conway Stewart Tavy, a pleasing blue-black ink (of which I have accumulated several bottles). It writes smoothly and I was delighted with the writing experience. The ink flow seemed ideal. Looking at the nib with a loupe, it appeared to be set up perfectly, with no suggestion of defects. It is a joy to have such a wonderful writing experience, straight out of the box. Although marked as a Fine nib, the line is perhaps closer to a Medium. The feed appears to be ebonite which is a rare luxury these days. As the feed absorbs some ink, an ebonite feed is thought to assist ink flow and to keep the nib moist, avoiding hard starts. It can also be adjusted to the nib quite easily by standing it in hot water for a little while, then squeezing it against the nib to fit its contours.

Disassembly.

The nib until can be removed by unscrewing it. Be careful not to lose the silicone washer on the back of the nib housing. The nib unit is interchangeable with the nibs of the Asvine V800 vac filler (another pen which I much enjoy using), although you would need to transfer the P140’s silicone nib washer from the back of the nib housing, if inserting a nib from the V800.

The piston mechanism is removable. It can be unscrewed, using an Asvine wrench (supplied with the V800) with prongs which fit into the two notches on the rim of the piston housing. Having just removed my piston and then reassembled it, (after some difficulty) I can set out a few tips here:

Removing the piston:

1. Turn the piston knob (“the cone”) pushing the plunger downwards and to open a gap between the cone and the barrel.
2. Insert the prongs of the wrench into the two notches of the piston housing, as deeply as possible so that the handle of the wrench is at right-angles to the pen body.
3. Screw down the cone, to trap the wrench in place.
4. Rotate the wrench. (To unscrew = clockwise).
5. Then withdraw the piston mechanism from the barrel. It is advisable to leave the piston mechanism intact, with the wrench still gripped by the cone. This makes it easy to reassemble. Some grease can be applied to the black silicone plunger.
6. A metal ring, which sits in a recess at the back of the barrel, may fall out once the piston is removed. Take care not to lose it.

I had not disassembled a piston prior to writing this post, but having a demonstrator pen lends itself to such an experiment, as you can watch the piston working. The mechanism separates into three parts, which I will call (a) the cone (with the helical shaft attached); (b) the bush, or housing: and (c) the piston shaft, with the rubber plunger at the end.

The slightly tricky part is putting these back together again, in such a way that the piston operates normally, and the cone tightens down onto the barrel without leaving any gap, when the piston is drawn up. On my first few attempts, I had a gap: the piston shaft had been fully raised, before the cone had screwed down to the barrel.

To resolve this, the cone needs to be screwed down on the bush part of the way, before the piston shaft is inserted at the opposite end of the bush. It may need a bit of trial and error to get this right. I found that the following method works:-

Replacing and adjusting the piston:

1. With the three components of the piston separated, first screw the cone onto the bush: whilst it will take approximately 11 turns to screw down all the way, try just 4 turns.
2. Then introduce the piston shaft into the other end of the bush and turn the cone some more, so that the threads connect.
3. Check that the cone can then be screwed the rest of the way down onto the bush, with no gap and the piston drawn up to its raised position.
4. Once correct, loosen the cone again and insert the wrench and tighten down to grip the wrench.
5. Insert the metal ring into the top of the barrel and then insert the piston unit (three parts all attached) into the barrel and tighten. (Note: to tighten = anti-clockwise). This needs to be fairly tight, so that the piston is secure in the barrel and does not unscrew when the cone is operated later but not too tight otherwise the acrylic will crack).
6. Remove wrench. Having greased the plunger, operate the piston up and down a few times to distribute the grease and to check for proper operation.

Conclusions.

I am thrilled with the pen. At the pen club, a few friends who had discovered this model before me, (some having more than one!) also spoke well of their experiences with the pen. One friend got out her Montblanc 149 to compare along side my P140. The similarities in shape and size were uncanny!

I deliberately chose an ink for this pen that is one of my favourites and not one that I am likely to want to flush before using the fill. I imagine that one fill may last a few months. Also, being a demonstrator, it is obviously advisable to avoid any inks which are known to stain.

This pen is one of a growing number of my pens that makes me think (at least for a while) that I do not need to buy any more pens. With the pen having so much to commend it and at a price which is so affordable, it makes you wonder how the rest of the pen manufacturers can compete and retain a place in the market. The Majohn P140 might not be to everyone’s taste but for those who enjoy a large pen, with a piston fill mechanism, an oversize nib and an ebonite feed, this one does currently seem hard to beat.