If the riff or the phrase is too fast,.. try to slow it down even by 50%
You will see how things are getting so simple like that.
When a student is telling me:”Oh this solo is so fast I cant play it!”
Always the same answer :”As long as we keep the notations and play in time, we can slow it down!
You are still playing the solo and it is better that way rather playing it fast and sloppy”
So don’t be a shame to do so