120mm?
One of the Bucks villages we passed thorugh on Monday had the highest speed humps I've ever seen. At each end of the village, where there was also a width restriction. I know the +4 would not have got over them, fortunately no problem getting one track on the hump in the 4/4.
I could see David in my mirror, in his Roadster 100, being extremely careful!
Cheers,
