I wouldn't. But you're not me and I don't date dudes, so let's talk it out.
No, there's no set time for a guy to decide if he loves you or not. Guys are notoriously slow to admit how they feel, but at least this guy is coming right out and saying he doesn't love you. I give him credit for honesty.
But I don't really buy the "hopes for the future" bit. If he doesn't love you after nearly a year and a half, I don't think he ever will, as much as he'd like to think his feelings will magically change. He's had plenty of time already to sort it out. If you were talking about marriage, that'd be one thing, but he's not even sure he loves you after this long? That's a problem. It's not like you're asking for a commitment here, just assurance that your feelings will be reciprocated sooner or later.
Even if he's right, even if one day he gets struck by lightning or has a near-death experience or just pops up and decides, "Ya know, I think I do love this gal," who wants to wait for that? How long will it take? How patient are you?
It's not the time that's the problem, anyway; it's the principle. Are you willing to sit in limbo while a guy figures out if he even has strong feelings for you? Before you answer, know this: given how he feels now, he's much more likely to wake up one day and say, "I don't think this is working," than he is to say, "Okay, I love you now." And then you will have waited all the time with bupkus to show for it.
There's also the chance that he's full of crap, and using the "hope of future love" line to keep tappin' dat ass until you realize what's going on. He wouldn't be the first.
Whatever his motives or reasons, I think you're setting yourself up for heartbreak, not to mention a whole lot of time wasted on someone who's unsure instead of someone who's smitten with you from the start and doesn't have to write out a list of pros and cons or consult his Magic 8-Ball to decide if he loves you. He might be a great guy, he might mean well, but it's a bum deal for you no matter how you slice it.
I wouldn't wait, but then, I'm not you. You have to make the decision, and I wish you luck with it.