Oops --- Looks like I ordered a 110/90-19 from JC Whitney.
Is this dangerous or should I just slow down a little in the curves?
Personally, I would send it back and get the correct size -- it really does make a big difference in the way the bike feels and handles. I wouldn't say the handling gets dangerous with the bigger tire, but it makes the bike feel about 75 pounds heavier. You'll just enjoy the bike a lot more with the correct size tire. But then again, I'm a lot more picky about handling than most, so it's up to you.
TiresUnlimited is right up the road from you in Dayton. They are a very reputable tire vendor with excellent prices, and they stock what they sell, including a huge range of brands and sizes for vintage bikes. I bet with shipping, they're cheaper than JCW for CS tires, too. I usually get my tires the next day via UPS in Indianapolis.
http://tiresunlimited.com