Originally Posted by DirkW
Only if you were already at the limit with 45/25. After all, it's just gearing up by about half a tooth (since you also use a larger spur gear). Should work just fine.
I've never run those gearing, I only ran 19/48 so far but I just got a 26t pinion and will be ordering a 46t spur.
What do you mean by "at the limit"?