high speed wobble - experiences and how to get over being "speed shy"

All of those are good suggestions, and usually work. Also check the tension on your headset -- make sure it's not pitted, and that it doesn't have any slop.

There are a couple other possibilities as well...

When I first got my TiCycles Softride bike, I had a Trek carbon fork installed on it. It was the lightest one at the time, and I was a bit of a weight weenie. Well... first TT on that bike, slapped on the Tri-Spokes, and headed out for a 36 mile TT into the back country. Any time I got over 30 mph, the front wheel would shake violently. Nothing I did would help -- hugging the bike with my knees, weighting the front wheel, loosening grip... I replaced the fork with a Kestrel EMS, and I never had another issue. Turns out the fork was just too soft (flexible). The aero front plus that fork just was a BAD combination.

Also, in the "cheap fixes" category, make sure the front quick release is TIGHT on that wheel. And don't use boutique titanium skewers.

I had that problem for a long while - I'd get to about 30, 35 and the front would start to shimmy and I'd have to sit up and hit the brakes. 

I tried everything.  Got the bike tuned, retuned, retuned again, all at different shops.  Got the wheels trued up, yadda, yadda.  What solved it for me was changing the tire.  New tire, and it just took care of everthing. 

Now the only thing that'll slow me on the downhills are gusting winds...and turns. 

Yeah, bike materials, your profile (weight), input to the bike (cadence, grip, road surface, etc), frame harmonics, fork material, wheels, skewers, tires, tubes all play a role. It's pretty hard to pinpoint one particular causal for the wobble.

The easy-to-change things are, in order of easiness (and cost): 1) take a different bike down the same pitch. Could be just the road and it's bob and sway, not your bike. Road is a major input... 2) your technique(assume you've tried this), 3) your wheel-tire-tube combo. I'd start by borrowing a front wheel and swapping a skewer and trying again, 4) tuneup as you might have a misadjusted headset (per what dave said), 5) change the fork, and 6) ditch the frame.

Good luck. Wobble is scary. I vote against it.

Google: death wobble bicycle

It's common and doesn't mean any component is bad, just the combo creates a bad frequency vibration at a certain speed. If you get it, switching bits (from cheapest to expensive) can solve the problem. Also, 2 identical people with the exact same equipment - one might get deathwobble the other won't. Can't predict. Key is not to freak out and try and muscle out of it - just slow down/coast and it will go away. Squeeze your knees to the frame, hold the bars loosely.

Thanks for the input everyone. This happened earlier in the ride and not on Polar hill. Guess I should ride these wheelset a bit more. I have an oly next month and then Vineman full in July. Neither are hilly compared to Wildflower.

I figure the more familiar I am with the nuances, the more prepared I can be if something happens.