Will 2.8 inch tyres fit in the mountain bike rack or does it need the fat rack?Updated 4 months ago

Some of the newer plus size MTB tires have extra-large shoulder lugs (tread) which take the overall width past the actual measurement marked on the sidewall. If your tires have extra wide lugs you can still work to our sizes in our guide but it will be a tighter fit and will mean you have to push it into the rack and pull harder on the bike to dislodge it when you remove it. 

So yes it should fit in a mountain bike rack but will be a firm fit. If you don’t want to do that you should go to the next size up to the Fat Rack. The bike will sit nicely in the rack but the front wheel may fall to one side slightly due to the larger gap but it will be very easy to unload.