UK speed limits are a bone of contention with many drivers, but they are a vital part of the UK’s road network. They are the front line of road safety, as they dictate the speed of all traffic, and by setting maximum speeds for different types of road, it means consistent regulation across the country. It also means it’s easier to prosecute those that exceed the speed limit, whether it’s by police enforcement, or via the use of technology.

While the use of speed limits is an issue that can be discussed until the cows come home, speed limits are there, and a safe driver will know that they are in place for a reason, so will adjust their driving accordingly. To help you stick to these basic laws of the road, we’ve compiled this feature to help you stay on the right side of the limit, even if you’re driving a vehicle that requires you to know a different set of limits to the ones posted.

If you’ve passed your driving test, then the round speed limit signs will be some of the first pieces of road furniture that you will need to be able to identify. They are unique, with a white circle surrounded in red with black numbers within. These cover 20mph, 30mph, 40mph, 50mph and sometimes 60mph. In addition, there’s the National Speed Limit sign, which is a white circle with a black diagonal line through it. This means the national limit applies, which is 60mph on single carriageway roads, and 70mph on dual carriageways.

However, as time passes, many drivers that simply use their cars to get from A to B without any involvement could even forget what the assorted limits are.To make matters worse, speed limits can be changed on roads without much in the way of notification, then there are other limits you need to be aware of, such as variable limits on smart motorways, or reduced speeds when roadworks are put in place.

When you’re behind the wheel of a vehicle other than a conventional car, or if you’re using your car to tow a caravan or trailer, then the speed limit that’s posted at the roadside won’t necessarily apply. These limits could be difficult to work out, but they will definitely be lower than the posted maximum you see on road signs. They will vary depending on the type of vehicle you’re driving, too and when you add-in regional variations between Scotand and England and Wales, then it’s easy to be confused about which speed limit is the right one for you to stick to.

ur kids admitted that they spilled soda on the passenger-side belt buckle of the car they use. Now it doesn’t latch in cold weather — not a good thing in Minnesota. My son’s solution is to pour water on it and park it in the garage until it dries out. Not only would that make a mess, but one guess whose car would sit outside in the meantime? I’m also concerned that that would screw up whatever electrical sensors tell the car that the belt is buckled.

My husband says to spray it with WD-40. I know from working with locks that that will eventually gum up the works. I’d wager that the graphite I would use on a lock would mix with the pop and gum things up, too. Given that it’s essential safety equipment and I don’t want the kids to die, I think it should go to the dealer to be fixed. Any support for any of our solutions? — Lisa

Hm, what dissolves sugar? I know! Hot coffee!

No, don’t pour black coffee on it, Lisa. What you need is a solvent — something to dissolve the sugar that’s gumming up the latch mechanism. And you have little to lose by trying to fix this yourself. If it doesn’t work, the worst that’ll happen is that you’ll then have to take the car to the dealer and have the seat belt latch replaced.

So my suggestion would be to try a product called Contact Cleaner, made by CRC. That’s a fast-evaporating spray-on solvent that’s designed to be used on sensitive electronics. So it’s very unlikely to damage anything.

Since you don’t want the kids to die, I’d have your husband apply this stuff, since it might dissolve brain cells, too. And since he’s obviously already lost most of his already, let him take the risk. The kids might still need theirs.

I would get a few rags and cover up the surrounding area, because gunk might drip out. Then spray Contact Cleaner liberally inside the latching mechanism. Then work it — latch and unlatch the seat belt a number of times. If it seems to be helping at all, keep doing it. I’d do it in the garage and leave the car’s windows open.

If it doesn’t work, you can try a stronger solvent — something like Brakleen, which dissolves even more stuff, including more brain cells.

And if nothing works, then you’ll need to put yourself at the mercy of the dealer, and deduct the cost from the kids’ soda allowance. Good luck, Lisa.