I'm a larger rider (190 lbs) and I struggle to find traction in tight twisties (e.g. grass crit, off camber tight stuff). I have used Challenge Fango tubulars for dry (32 rear for clearance, 34 front), Challenge Limus tubulars for mud. I'm constantly fighting for grip on the rear tire with the Fangos in any fast / power corner. Recently, I flatted my Fango in a race and switched to a pit clincher with a Kenda Kwick on it - I was surprised how much more traction I got from the side knobs.
Maybe I need a tubular with more prominent shoulder knobs but that will still clear some tight chainstays? Any advice welcome.
PS - the Limus hooks up great for me, but it's too slow too run in anything but gumbo mud.
what pressure are you running? I am your weight (6'3, 195), and have had no problems with rear grip running grifo's for the past 20+ races. The fango has the better side knob, but less forward grip than grifo. All else being equal, it's better to wash the rear out than front. I'd say look at your pressures and cornering technique. Maybe you are folding the tire when powering during a corner?
I'm usually running 34.5 rear / 33 front. I find that anything below 34 does lead to folding, but 34.5-35.5 (depending on the course) seems to keep it round. I agree on washing out the back and not the front - I've setup my fore-aft weighting to get the back to go first.
On cornering technique - I try to observe the lines the buck-forty guys take, but I always lose a little bit on every grass crit section. After trying alternatives, I usually settle on a wider line, riding the course tape on the entry and exit to hold whatever speed I can.
I love the casing / ride of the Fangos on the straight sections. I just feel like I need more shoulder knobs to keep my mass upright when I get into the tight sections.
Well, I don't know that you are going to find a better shoulder than the fango... that's about as good as it gets. You WILL have to take different lines, and assuming you have more power than lots of those little guys, if you can learn to keep that power rolling, and lose less speed, you should be able to hang in twisties, and get some time in the flat fast sections.
watch some video of trebon vs the field. He takes slightly different lines than many of the others, and isn't really even that much heavier (i think he goes 170). Sounds like you have pressure and setup in the right direction. I would really think it's more technique than anything. Maybe borrow a grifo and see if you have the same problems with that tire running same pressures as fango. If the problem is the same and not worse, i would say it's not the tire, cause the fango should grip much better than the grifo.
If you do find the magical solution, be sure to report back. I have been toying with Limus front, XS rear lately and have been loving it, with very little 'wash out' in the rear... but I am more prone to losing the front wheel cause of my long seatpost and increased setback cause of my long legs and femurs