Regardless of bike, I never have been able to make handlebar muffs work safely.
Winter use I have pair of Harley leather mitts, purchased in '66, cheap ski gloves in side, they work down into 20's F.
Better is from Aerostich #442 Triple Digit Gloe covers, rise high over wrist and WATERPROOF-$47----I had a pr but cannot find them.
Problem is makers/designer don't seem to ride......windshields/fairing should include hand protection......would make riding in cold/wet better. "Bat-Wing" fairings keep quite a bit more of the weather off you hands.
Have tried "enduro" hand guards....they keep little of the weather off you hands.