Question about 1 1/8" to 1" threadless stem shim
 

I'm building an old lugged steel frame with modern components.

The fork I would like to use is a Columbus Minimal, it's a threadless 1" fork.

I really want to use a DEDA Zero 2 stem. (I think the fork clamp area is pretty slim, and it would look acceptable with the skinny head tube and steerer even tho the stem is 1 1/8 so it's bulkier. And it's pretty cheap.)

Wiggle | Deda Zero 2 Stem 2014 | Stems

Now I have to find a stem shim. The clamp height of the stem is 38mm according to a few websites. With most stem shims there is zero information about how tall they are. I found this Thomson, it's 37mm tall.

Wiggle | Thomson X2/X4 Stem Steerer Shim | Stems

My question is would this shim work with the 38mm clamp height stem? I want to have a 5mm spacer above the stem.

Personally i've never used a stem shim before, so I have zero experience with the topic. :( I don't know if that 1mm matters, I just want to be safe since we are talking about the stem clamping on the steerer here... :twitchy:

That shim will work fine and the 1 mm height difference is not an issue. The shim itself has nothing to do with whether you can put a spacer above the stem and if the steerer tube is long enough the shim has no effect. You will need to use a a 1" spacer.

I have exactly the same set-up on one bike. The frame requires a 1" steerer has a threadless headset and fork and I have a 1-1/8" stem and the required shim. I use a stack of 1" spacers below the stem, the stem and shim and then a 1" spacer above the stem.

BTW, if you find a shim that is too tall, it can be cut to length just like a too tall steerer.