I have a 2001 Hionda ACE 750...can I use car antifreeze in it? It never seems to be low butjust in case is the antifreezw/summer coolant the same for cars and motorcycles? 

No, you can not (unless for emergencies on the road). The have different properties. If you use auto....flush and replace ASAP.

There are only a few car coolants you can use, they have to be "siI use licate Free" and say so or your water pump will go out! I used a "Dex Cool" anti free that says no "Silicates " etc on the bottle!

As long as the antifreeze is aproved for use in aluminum engines, you are good to go. It should say on the container " safe to use in aluminum engines " I use the 50/50 pre-mixed with no problems !!

I use only motorcycle specific coolant,not sure why you would use any type of auto coolant except in emergency,n only w/caution.
sweet looking ride !!!

I was told by an older motorcycle mechanic years ago " That if you want to buy car parts for you bike then maybe you should drive a car and give up riding"

I've always used Prestone, either color.
I have three Honda motorcycles one with nearly 200,000 trouble-free miles, the others with over 70,000, each.
Coolant containing silicate is a rarity, these days. There is no difference in auto and motorcycle coolant, except for additives used in serious racing.

Go to Walmart, buy coolant, mix 50/50 with filtered or distilled water.