Originally Posted by Iride01

Chain line of GRX cranks is 47 mm. Most 11 or so speed road bikes expect a chain line to be about 43.5 mm.

I'm just not sure why you'd want to insist on putting a GRX crank on your road bike unless the chain line, which is determined by your rear cassette position is not what a 11 speed road bike will have.

If you are trying to get a smaller size of chain rings, then there are better options.


edit... coming back to this I realize now that the OP did state it was for an older Mountain Bike. So just take where I said road bike out of the text and substitute older mountain bike. Older mountain bikes had narrower chain lines than what GRX is made for.