Tunk Times #18
July 2026
It’s quiet at the office after a hot weekend but the Tunk antennae aimed at the internet are picking up messages constantly.
Seems like the reach of our brand is growing steadily and we have started to get different kinds of co-operation offers. We got to do a photoshoot for Brooks and their new product launch which was fun. Then we got our first frame retailer from ACE! Cycles in Berlin, whom I (aki) met at Fenderfest, as they had a spare rim to sell me after my own cracked on the first day. We ended up talking business as well and now they have a frame to show off in Berlin. ‘Luck in an accident’ goes the Finnish saying!
We also got some embroidered metalhead patches made, with a design by Eric from Low Pressure Zine. This project was started months ago but things take time and we are pretty slow and careful! They were embroidered locally at Clobber Helsinki, a stone’s throw away from our HQ, which is nice (last time we ordered little Tunk patches from a Finnish company they came dropshipped from China…).
All the people and companies we now get to do stuff with have been great, but a question is raised, that at some point we will have to start saying no, and deciding on what parties to work with will be interesting! We don’t want to dilute our own thing just for short-term visibility.
The bad news is that our stems did not pass safety testing. Seeing the Zedler Institut report again with the red “not ok” -label was disappointing to say the least. The biggest problem is that due to some misunderstanding in communication, Fort has already made all the stems to an almost-ready state, and they cannot really be changed much. It just might be that we have some paper weights that look like stems to sell soon…
We were surprised that they didn’t pass, but then again not at all surprised, after what we learned through the front fork testing process. We wanted a light and slim stem, made from steel, again the type of product that almost no one is making so there is little information about them.
The stems cracked on the clamp part, behind the handlebar binders, next to the welding seam. The clamping areas were made with 1,5mm cromo steel tubing and the extension with 1,0mm tubing with 25,mm OD. These are not ultra-light specifications, and I would think many custom builders use similar materials and techniques.
We are not saying they also make dangerous stems, but rather that the EN ISO standard is quite strict on some parts, even if Zedler says it is not strict or realistic at all and everything should actually be tested to a much higher standard.
Maybe it’s also somewhat the differences in materials, steel usually breaking in a more controlled and slower way than aluminum or carbon, which will break very quickly after a crack is started, so aluminum stems need a higher safety factor? Or then we simply have a poor design in some way we haven’t understood yet.
Are the slim steel stems unsafe, probably not, but maybe they are not as durable and strong as they could be? This is just speculating of course. In general one sees surprisingly few broken stems, even in old super light quill stems.
Different types of welds and braze joints, heavier tubing, stronger material, bigger diameter et cetera might help, but let’s see if we have the drive and financial means to continue the project… Every test costs us around 1000 euro, so we need to sell quite a lot of stems just to make even after a few of those! And it’s not that there aren’t functional threadless stems on the market, just that none of them look right on a slender steel frame! We have nice (definitely not safety tested) unique custom stems on our own bikes, and would want other people to have nice stems as well. We shall see what happens.
On the positive side, frames have been selling quite nicely, and many have bought wheelsets and small parts to go with them. That is very reassuring and seems the second batch of frames will need to be made soon as these are running out!
For the art supplement this time we have the patch design from Eric! Our idea for it was a “horrible and impenetrable path of painful tunking” or something along those lines, and it sure came out like that! These will be available as embroidered patches in the webshop, right after this newsletter gets sent!
Until next Times
Tunk Crew
ps. We are still open to visitors every wednesday from 12-18
