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stpauls

IRC tyres

31 posts in this topic

Do IRC rear tyres still come off the modern Motad-style rims when inflated at very low pressures,  2 - 3 psi?

If so, then why don't the manufacturers make the bead a bit smaller/reduce it's circumference?

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Why run the pressure so low ?  IRC tires have very soft side walls, although I suppose if it's going to come off a pound or two won't make any difference.

 

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 It`s supposed to be the rim that is slightly off on tolerance.

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They're both supposed to be made to a standard, to ensure compatability.  Such a quality control issue ahould not have existed for as long as it has.

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IRC tyres changed their design?

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"These tyres are the brand new 2017 model with the re-designed bead to fit modern rims better. "

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Yes the revised irc still come off the rim. Multiple rims. We are calling them "i r ceeing you dnf any moment". At 5 to 6 psi the leak slowly and around 3 ish become a bracelet. My dunlop d803gp's have ridden half a loop in sections flat (only on the bottom mind you) just to make their way back to the pits for a repair. I have found the sidewall on the irc to be stiffer not softer.

--Biff

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having problems with the dunlop 803gp anythink below 6psi and it goes  flat.absolute rubbish tyre

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I remember hearing that some of the wheels have a bit of issues with some tires... So, what kind of wheel do you have? 

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I'm have tried a new type IRC that isn't supposed to deflate.

Starting pressure on lap 1.   4 psi

Finishing pressure.   3.5 psi

Starting pressure on lap 2.   4 psi

Finishing pressure.   2.5 psi.

This was a rocky two lap road trial. Probably better result than older IRC but still far from acceptable.

I have now given the bead two coats of Tip Top bead sealer to see if it will help. 

Lomax road trial on Monday will test it!

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On 06/04/2017 at 11:02 PM, biffsgasgas said:

Yes the revised irc still come off the rim. Multiple rims. We are calling them "i r ceeing you dnf any moment". At 5 to 6 psi the leak slowly and around 3 ish become a bracelet. My dunlop d803gp's have ridden half a loop in sections flat (only on the bottom mind you) just to make their way back to the pits for a repair. I have found the sidewall on the irc to be stiffer not softer.

--Biff

You are right. They have a stiffer sidewall and softer tread area.

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