Speeding on a private road

Hello,
I am the owner of a private road and my neighbour has a right of way through it to his home. The only problem is that he and his wife drive way too fast for the road conditions (very narrow and one blind turn). I have almost been hit by them a few times. On one occasion, he came around the turn and slid about 40 feet before he hit the ditch and came to a rest only inches from my car. When the issue is brought up, they will usually drive even faster. They drive a toyota landcruiser and I drive a renault laguna so it is easy to see who would come out worst in a head on crash. This is a real worry as my toddler and newborn are often in the back of the car. Is there anything that I can do to slow them down?
Thanks

Install a few ramps (and sign post it) so they'll have to slow down.

I would go one better and install a small chicane, three bollards / islands in an S shape. This will force your inconsiderate neighbour to slow down. But as it is a private road make sure you erect a warning and a speed limit sign, though bear in mind the speed sign has no basis law as you are on a private road.

If all else fails just insert expanding builders foam in his exhaust pipe

I'm guessing that as you are the owner of the road you can do pretty much whatever you want to it - as long as their right of way is not impeded.

I'd go with something like theoneill's suggestion.

Thanks for all the replies,

Think I might try the speed bumps. The bollards sound good but I think that they may restrict traffic to small vehicles. As I own a farm, I would have artic lorrys using the road frequently as would my neighbour. I was considering installing an automatic raising barrier arm (like the ones in car parks). Would this impede my neighbours right of way?