Clip on aerobar installation problem

My girlfriend has a 2002 Cannondale that came with a 3T Zep XL bar, 31.8. She is doing her first duathlon next weekend so we got her a pair on Profile clip on aerobars. I was concerned about the bulge factor in the handlebars, but could find no information (on the website or instructions) that they would not work. When we installed them, they wanted to slip outwards due to the bulge. They just don’t want to get tight and I don’t want to over-tighten and possibly damage the bar. I called Profile. The woman assumed I bought the wrong aerobar (not 31.8 compatible) then asked the boss the deal. He said they don’t work because of the bulge. She suggested I buy a new handlebar! I suggested they put a notice on their website and in the instructions that they don’t work.

With that said, does anyone have a solution/idea (other than buying a new bar)?

Thanks

Good for you. You’re pretty much right, and somewhat justifyably disgruntled. We have had problems with this here in our store. Right now, our company line is that, with a couple exceptions where we have done it ourselves to be sure it works- we don’t mount aerobars on oversize handlebars. Although there are some aerobars well designed to work on the 31.8 diameter, it is the taper of the bulge (as you pointed out) that creates the problem. I know this is of no comfort to you, but you are right. It really doesn’t work very well at all. Personally, I’m sticking with 26.0 diameter bars for my tri bikes and those of my customers. Good luck- this is a hassle.