I have recently decided to try out heat training, but I wanted to avoid paying an absolute fortune for the CORE body temperature sensor. I instead decided to give this a go:
https://www.aliexpress.com/item/1005007923415002.html

It is IP22 certified against water and dust, but I can also certify it against heavy sweating, at least after a few sessions. The app that is promoted with the product requires creating an account, and for some reason syncs everything to the cloud; I instead recommend using the Tempal app.

The only problem I currently have is figuring out how to securely attach it to my armpit. I am using the heart rate monitor strap for now, but it only works as long as I am not moving too much. I also just ordered an elastic hand band (https://www.aliexpress.com/item/32833627238.html), which is going to take some time to arrive, but I think it should work much better. In the meantime, do you have any DIY ideas for how to attach the thermometer securely to my armpit?

You can look it up. Rose themself says that they let the carbon and alloy frames be made in China (speeder could it be) and than imported back to Germay. Only the assembly and R&D are in Germany.

Tcheu ste panthere https://youtu.be/CrRkv7e3exc? This video was peak internet. It's down the road from my place in the mountains, puts a smile on my face every time, and i've watched it well over 100x.
It's just fancy car vinyl decals, the whole bike cost 10 euro in stickers, i found a friendly neighbor with a plotter machine. It's fully reversible (I half ghetto spray painted a bike last year, i regret it already).
In the last 2 years i built 9 bikes and rebuilt 1. I have too many bikes as well as friends who are supporting my toxic habit It's a hobby that occupies way too much space in my head.
Facteur & tractor is ofc me trolling Factor. This frame looks a lot like a factor Ostro something.

logged around 103kms already... the bike is stiff compared to my old bike, feels like a solid wall...
i dont know if its just in my head but once you roll, you want to full gas all the time, it feels light or whatsoever cant explain but i am gasping 
need to get use with the handlebar height, it was 2cm lower than my old bike, riding/sprinting on the drop needs more training...
my favorite part is the brake... very far from the rim brake, bite right away and no worries of wear on the rims...
as we said, maybe we are just enjoying our build... i just hope not to see any cracks soon...