Mycket snurr om kolv dimensionen på bromscylindern på de amerikanska forumen.

Well, I'm sure 45146-04 is 1/2" so you'll get the right thing. But, did they really tell you that all rubber mounts having 1/2" master cylinders??? All the single caliper 07-up bikes are 11mm. That is not only according to the FSM, but also the m/c I pulled off my 2007 883L. On 2007-up bikes, only the XL dual caliper models (like the 1200R and 883R) have 1/2".

Doesn't matter for you, just kinda interesting that's what you were told.

Sorry I misspoke. Actually I ask the parts guy if the 04-06 m/c were 1/2" bore. He didn't know, and had to check the manual. After a few minutes he comes back and tells me, yes the manual says 04 are 1/2 bore, and 45146-04 doesn't change till 07. Then he said he thinks the only difference in 07 was they went to dot 4. I assumed that meant they were 1/2" bore in 07 too, but I didn't ask him to check the manual to find out.

This must be what you're talking about.
11 mm is = to 0.433071 inch so I don't think I would want that size.