I have a road bike from Circa 2003 and it currently boasts an ITM Millenium stem. The stem is a bit long for my liking at around 130mm and I was thinking of replacing it with a shorter one for a slightly more upright riding position.
I have a feeling my bars however are of clamping diameter 25.4 mm, although they may be 26mm as it is an Italian bike (ITM bars too). Shopping around I notice that pretty much all new stems are of the oversize 31.8 mm clamping diameter so I assume they won't fit my bars.
How would I get around this problem? I heard one could get shims to thicken the bars at the clamping point but sourcing them seems to be tricky.