I am not a tire expert, I am not an engineer.
I suggest you run the OEM size front radial tire (though the VMax Gen 1 didn't come with radial tires). Also, use the same brand and type of tires, as mixing manufacturers, types of construction and compounds can make for an evil-handling motorcycle. I've posted and contributed to numerous threads about this.
I have this bolt-on wheel, a 5-1/2" X 18" size available. PM me if interested.
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A better front wheel to have would be a 3-1/2" X 18" which is wider than the OEM. Also, you probably won't find a same as OEM aspect ratio sized tire, and will have to go with a lower aspect ratio, as that's all that is available. I run a 110 radial on a stock front wheel, and while the width isn't optimal, it works.