Wobbly wheels/cones - effect on performance

[grellboy]

When I lift my bike there is a bit of a dull rattling noise, so yesterday I flipped it over and sure enough both wheels had lots of lateral play. At first I thought it might be qr skewers not done up tight enough but this wasn't the case. A bit of googling suggested that the cones are loose (whatever that means) but further googling also suggested that this job is well beyond my ability. Therefore I have two questions: a) what effect do these loose cones have on my bike's performance and b) what's it gonna cost to sort the pair at my Lbs?

 

[Fab Foodie]

It won't unduly affect performance but it will hasten the end of your wheel bearings/ hubs.

It's an easy-peasy job with a couple of inexpensive cone spanners.

 

[Tim Hall]

I'm out of touch with workshop prices, but I can't see it being too spendy as, like FabFoodie says, it's a simple task. Of course the hubs or the cones might have already got damaged, which will mean more money needed.

 

[guitarpete247]

There's lots of guides ont' tinterweb. Here's one:

View: https://www.youtube.com/watch?v=jZp-9xQfzJo