General fat bike questions and advice on specific frame recommendations

[Flying Trunk Monkey]

Hi all, I'm not well versed in all of the fat bike standards so I have several general questions about that which will hopefully lead me picking a chiner frame to build.

What I want (...or what I think I want unless you guys give me better advice)

Honestly I DO NOT think I want an actual fat bike, but I do want a bike that will provide LOTS of tire clearance (for fenders and mud) for up to 3" 29er tires.
1) Could I build a fat bike with either 27.5" or 29" and mount 3" tires on it? Realistically I'd more than likely run a 2.2-2.6 29" tire but I'd like the option to run a 3" and could buy a 27.5 wheel set if necessary.

It seems symmetric 170mm rear hub frames are the direction things are going toward now.
2) Is there a symmetric, hard tail, 170mm frame with a 100mm BB available?

Heck, for my needs I could likely do well with a narrower 142 or 146mm rear hub but I'm assuming they don't make a fat bike frame that will take such a hub.

Are there any other options I should be aware of? I'm assuming 100mm is the narrowest BB width for a fatty but my preference would be to go as narrow as possible.

[lRaphl]

Looking at your needs, you should look for a 29+ instead since you want to run 29x3" as the biggest tires.

For hub spacing, I think 197 rear and 150 front is where everthing is aiming right now in order to fit big tires like the Snowshoe XXL (26x5.05").

[Flying Trunk Monkey]

Looking at your needs, you should look for a 29+ instead since you want to run 29x3" as the biggest tires.

For hub spacing, I think 197 rear and 150 front is where everthing is aiming right now in order to fit big ts like the Snowshoe XXL (26x5.05").

Thanks for the reply, after doing some Googling it appears you are correct in saying that almost everything moving toward 197mm rear hubs. I really want the option for wider tires with clearance without the chainstay length that the big tire capable 197mm hub frames come with. I might be looking at a custom design.

[emu26]

I would suggest then that you look at a 27.5+ frame, there are several options available in these that allow you to run 27.5 x 3 rear tyres, and some that only go to 2.8, most seem to be with boost spacing so 148mm hubs.  The 27.5 + will get you a diameter close to, but not quite, a "standard" 29er wheel / tyre combo, it also then allows you to run a normal 29er wheel / tyre combo if you find you don't like the feel of the + size rubber without having to fork out for a new frame.