I can pick up a set of 27" Rigida blue label 13-19 locally. Can I safely mount a set of 27"x1-1/4" tires on it or are those rims too narrow? Based on the information from Sheldon Brown's site, the widest tire for 13mm width rim is 25mm, 1-1/4" is more like 31.75mm. What is your 2 cents on this subject?

Edit: I just checked, the actual width of the tire is 26.3mm.