Jon, I am lead to believe that Motocross tubes are not recommended for road use, definitely a case of thicker not being better, something to do with generating heat.
Peter,
I did a bit more digging. I have contacted an Andy James, Operational Marketing Manager (Motorcycle & Scooter Products) at Michelin Tyre PLC. He initially said there was no real benefit to using thicker inner-tubes in order to prevent punctures but then I pointed out that I've fitted them to prevent punctures around the valve. He did say UHD tubes are not suitable for modern bikes ridden at sustained high speed useage but okey for older machines. This was his final reply, which i think is interesting.
Maybe the jury might still be out but I'm going to see how this UHD tube performs.
Cheers Jon
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Morning Jon,
Thanks for providing the additional information. A Michelin UHD tube on older lower performance machines won’t cause any problems at all in use. We should be looking at why inner tubes are failing though and remedy the cause not the symptoms. Splitting and tearing around the valve is usually down to corrosion or roughness in and around the valve hole in the wheel rim. Often this leads to an enlarging of the hole which allows excessive movement of the valve and subsequent wear. This can be remedied by sleeving the rim hole, and a flexible plastic washer could be used between the tube and rim. This enlargement and roughening of the area can often be in part due to incorrect fitment of the inner tube locknuts. It is very common to see one of the 2 locknuts fitted inside the wheel rim, bolting down the conical washer which is shaped to sit nicely directly against the rim and inner tube. The 1st lock nut should be run down to lightly touch the wheel rim, and then be backed off by half a turn and then the 2nd lock nut run down and the two tightened together before adding the valve cap. Locking the tube to the rim is not recommended, some leeway in this area is welcome so the tube and valve can flex naturally without restraint, hence backing off the lock nuts from being tight against the rim. Splits in the valve area can also be down to ageing of the inner tube - how old is it? Inner tubes should be changed at every tyre change, and on lower mileage vehicles we recommend for safety that tyres and inner tubes are changed at 10 years old regardless of tread wear. The valve hole can also allow contaminants in which can cause the valve to corrode. Having the lock-nuts very close to the wheel rim can help to avoid this, as can using a small amount of silicon sealer or grease on assembly.
Best regards, Andy JAMES
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