Joined: Jul 2014
Posts: 1,397
Likes: 169
From: Milton Keynes, England
Bikes: 2.6kw GT LTS e-tandem, 250w Voodoo, 250w solar recumbent trike, 3-speed shopper, Merlin ol/skl mtb, 80cc Ellswick
It really depends on the bike and kit.
My GT LTS-3 has a 56T chainring on the front, but I had to use a longer bottom bracket (square taper) to clear the chain stays.
More an issue, I still had to use different cranks, as the Shimano 105 cranks collided with the chain stays as they passed over.
If you have the more modern design of external bearings, I don't know if you can fit a road crank and space it adequately. And these days you're lucky to find large road chain rings to fit an MTB crank, as they're all over-styled and keyed-fitment (you know where you are with 5x130).
The derailleur height is one problem, but you may also need a different cage, as most MTB cages start colliding by around 48T even when raised to the correct height.
It's likely to be a tin of worms.