The down force of the A1 cars on the street track in China is sucking up the manhole covers. Back when the F1 cars went to Long Beach in 1979 the same thing happend one of the covers hit the bottom of James Hunts Wolf severing the break line and perhaps prompting the former champion to really think about quiting.
In Monaco there are no manhole covers on the racing line, although if a driver goes off line he might still encounter them. The bump between Casino and Mirabou is where a manhole was, but it was tarmacked over in the late `60s.

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John.

"I am an artist. The track is my canvas, and the car is my brush."

- Graham Hill

Should be in General or Cafe.

Done.

The problem actually resurfaced at Shanghai, too - during the V8 Supercars of all things. A drainage grate wasn't bolted down correctly, and ripped the bottom out of Mark Winterbottom's Ford.

I wouldn't be surprised to find that the drain cover that popped up at Shanghai last year, ending Montoya's race, also did so for the same reason.

As a slight aside from this - manhole access covers are bolted down in Sydney. You need a special tool to open them - this stops people stealing them or gaining access to the sewer system without permission (although people do so anyway through the stormwater drains).

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Forza Cadel!

The A1 race in Beijing also faced a problem with the hairpin, it was too tight and the cars couldn't get around it. Eventually they moved the corner to a wider part of the street.

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To you from failing hands we throw the torch, be yours to hold it high

During a DTM race on the 18th of july 2004 a same thing accured in Shanghai, when Bernd Maylander colided at the start of the race with a manholecover.
The race was posponed and all the covers had to be looked at (72 in total)
Bernd Maylander wasn't hurt but his car was a mess.
This was also on the streetcircuit of Shanghai, I guess they haven't learn.

Very embarassing for all paries involved.

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Formula One America http://formulaoneamerica.blogspot.com/

It's not that they are not bolted down, the rim is working loose. They need to be welded.

The one that JPM hit last year wasn't pulled up aero, but was left up by a careless track worker. JPM took a wider line through that corner than anyone else and on that lap ran even wider.

__________________
John.

"I am an artist. The track is my canvas, and the car is my brush."

- Graham Hill

lol, isn't that just typical south-european style?
"Oh well.. we'll just put some tarmac over this 'ere.."