I bought a Winkku signal mirror about a week ago from http://www.buybuybicycles.com/. It's a brilliant product [pun intended]. A lot of thinking went into it's design. I like it.
Now for the quibbles: The bar end mount expander only acts on the end of the sleeve which doesn't give enough contact area to secure the mirror properly. I fixed this with electrical tape wrapped around one end of the sleeve. I did about 3 wraps full width, one wrap 2/3 width and 1 wrap 1/3 width. The end with the most wraps goes on the handle bar end obviously. That fixed the tightness problem and also eliminated the vibration. Simple
Quibble number two: The flasher switch is very sensitive and it easy to activate unintentional, especially with gloves on and the beeper is not loud enough to hear in traffic. I moved the twist throttle and put on a longer grip. That helped. My ultimate solution for this problem is a bit wacky and involves my granddaughters pink hand grips from her Barby Bike.
