Cyclocross - Why did my Poprad come with 25.4mm bars?

2007 Lemond Poprad. I have a drop bar (OEM) that is 25.4mm, which is a MTB size. Any ideas why they didn't just go with a 26mm or not a 31.8mm?

I'm thinking about getting a new stem and I was wondering if it makes sense to switch out the bars while I'm at it.

Not sure why Lemond chose 25.4, but I do have a few road bars that are that size as well.

Unless you really really really really want a specific stem that comes only in 26.0 or 31.8, I can't think of a good functional reason to change out the bars. There are lots of stem options that will give appropriate rise with a 25.4 clamp diameter. If you want new bars, that's a different question.

I am choosing Thomson stem and was trying to decide if I should get the 25.4mm or the 26mm (and use with a shim) to get the most cross-bike usage out of the one stem. I have a fixed gear bike that uses 26mm bars.

25.4 is not mtb size. It's a size that most mtbs happen to use. Nitto make bars in 25.4, so here is your excuse to get a noodle bar...

all of the bars on my five bikes, save one (31.8) that I swapped in on my cx bike, are 25.4

midges are also 25.4.

As far as I can tell, there's nothing inherently good or bad about it--it's just a different standard. Maybe the bigger sized road bars allow for butting to save weight?

I think the larger diameter tubing can be stiffer, but smaller gauge. So the bar is theoretically stiffer, yet lighter. I've found no functional difference in any of my bars, but I can barely flex spaghetti.