UK Karting - Notice Board (General Karting) : Re: Flat Tyres

Notice Board (General Karting)

Re: Flat Tyres
Posted by 'SimonS' on 09 Jan 2009 @ 10:04

| View Message Thread | Reply to this message |

SimonSJoined: December 2004
Total Posts: 4
[ View User Profile ]

"some of them go flat after a few days."

There's a whole host of things to check.

Obviously, you have taken the cores out of the valves and looked at them under a magnifying glass to make sure they don't have grit or corrosion or that the rubber mating face hasn't deformed or perished. Also, even in warm weather, deflating the tyre can produce enough ice to hold the valve open, if the tyre are stored in the cold, that may last long enough to allow the tyre to deflate.

You have also waggled the valve. I had one that had cracked where the insert tube ends and teh rubber is thick. The tyre held pressure and even passed a 5 minute dip test. When waggled the air rushed out.

You have examined the tyre bead to ensure that you don't have a cut across the face and the bead hasn't been deformed (one of the risks using tyre tongs is that you can bend or deform the bead wires permanently.

You have checked that the wheels are actually round and that the rim faces haven't been bent after an accident. This can push the bead inwards far enough that it is sitting on the bead retainer lip, rather than in the groove.

If you have bead retainer screws, then the O rings are in good condition

and you have done a dip test on the tyre/ rim.

Obviously you have swapped a tyre that stays inflated on one rim with a deflating tyre. If the 'good' tyre deflates, it's a rim problem, If the 'bad' tyre deflates on the good rim, it's a tyre problem.

If you still can't find a problem then its possible the aluminium rim is actually porous to the air, but normally that rim would always have slowly gone flat. If the rate of deflation is slow (several days) then it doesn't matter, so long as the tyre remains inflated for the race.

Or get a new tyre / new rim as appropriate.

Message Thread:

Flat Tyres by 'Aquila' (08 Jan 2009 @ 20:10)

Re: Flat Tyres by 'Dunny' (08 Jan 2009 @ 21:17)

Re: Flat Tyres by 'raceinstructor' (08 Jan 2009 @ 21:19)

Re: Flat Tyres by 'Aquila' (08 Jan 2009 @ 21:42)

Re: Flat Tyres by 'DanTheK1RaceGearMan' (08 Jan 2009 @ 21:45)

Re: Flat Tyres by 'raceinstructor' (08 Jan 2009 @ 21:54)

Re: Flat Tyres by 'buzzinrussell' (08 Jan 2009 @ 22:30)

Re: Flat Tyres by 'DanTheK1RaceGearMan' (08 Jan 2009 @ 22:52)

Re: Flat Tyres by 'SimonS' << You are here!

Re: Flat Tyres by 'Aquila' (09 Jan 2009 @ 16:32)

Re: Flat Tyres by 'DBaldwin' (09 Jan 2009 @ 19:23)

Re: Flat Tyres by 'Farrang' (09 Jan 2009 @ 20:46)

Re: Flat Tyres by 'TheBaron' (09 Jan 2009 @ 22:44)

Post a Reply:

You may post a direct reply to this message which will appear in this thread.
To post a new or unrelated message use This Form. Top of Page
Notice Board Index

[ UK Karting Main Index ]


News	Karts & Karting	Notice Board	Market Place	Companies Directory	Tracks Directory	Events Calendar	Race Results	Photo Gallery	Links