have just got a set of these for a new car, having previously used aquare bars. They come with a set of full length rubber inserts that fit in the track on teh top. I am assuming you use these if you have the bars fitted without any carriers etc, to keep them more aerodynamic or something ? or do you chop 'em up and put in between the carriers ?

Chop bits off as required. I used to have a roof box in the middle (leave rubber underneath roof box) and cut sections off either end for slide in bike racks. Keep cut off ends and reuse them when not using bike racks. It will cut down on noise a little bit.

Chop bits off as required…but if you don't use the T-clips (personally I wouldn't as I've seem a few fail – but I know many people who do and have no issues) then you need to chop gaps out for them to fit…if you aren't doing that then fit the rubber but make sure it isn't on a very cold or very warm day as the rubber will shrink extend depending on temp (and also may contract if you have stretched it out to get it to fit)…before trimming the excess off, leave it for a half hour or so so any contraction has been done.

Email Thule???

Thanks all.

Haven't heard of the T clips failing before ? – that's a bit of a worry……

I suspect it was due to overtightening, but I don't know…it doesn't look as secure as the clamp round the bar in my opinion. Like I said, plenty of folk use them so it was either a bad batch or hamfisted usage…