on my road bike. I 've got over sized bars - TTT Less XLs
great bars, but they are only 31.8 where the clamp covers the bar, then they slope dowward to something less than 26.
I can’t clamp my jammers too close to the stem because of the slope , beyond that, I can’t get em tight enough it seems.
anybody else have this problem?
how old are your jammers? I thought the new ones were compatible with 31.8.
but if you are saying that the bars are 31.8 under the stem clamp only, you are going to have a problem.
if that is the case, those style of drop bars may not work with probably any aero bars…
they are 31.8, 26 with the shims but I think this drop bar just may not be made for aerobars.
I can mount them, but can’t get em tight enough that they won’t move on me under pressure.
now i gotta decide whether to get rid of drop bars i love or live without the jammers…tough call I 'll tell ya. may have to go back the prima 199s but then i’d have to lose my bontrager racelite o/s stem…
part of what makes this sport so interesting. equipment 
Well, if the bar was the right size in the mounting area you would probably be able to get the aerobars decently tight.
I use drop bars as well, but use 26.0 3TTT Prima 199s with a similiar aerobars as yours and have no problems. try that…
Shims readily available from Madison. I mounted my 2004 Jammers on ‘non oversized’ bars no problem. You could try getting in touch with them. They were supplied free of charge. Visit the Profile website for details.
JC