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Non-UST tyres on UST rims?
Hi there,
I'm interested in buying some Fulcrum Red Metal 1's and have noticed on the instructions that you must only use UST tyres on these tubeless wheels.
Without getting into whether I should be tubeless or not 
, why couldn't I use inner tubes and normal tyres on these rims (assuming I remove the tubeless rim valve, etc)?
Also, if anyone has had any experience of these wheels, I'd be interested to hear your thoughts.
Thanks!
- Warren.
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UST is supposed to be a standard so all UST wheels need to have at least similar side walls in order to a UST bead to seat and lock in place. They only state that due to liability reasons so people (like me) using normal tyres tubeless would not complain in case of a tyre rolling off the wheel (never happened to me and I use low pressures 22f/28r).
Using normal tyres WITH tubes is safe!
Cheers
Hi Warren
I have Fulcrum Red Zone UST wheels on my bike. The only reason I can possible see that you can't fit normal tyres and tubes to these wheels, is they have a lip on the edge to better fit the UST bead to for sealing. It would be very easy to pinch tubes here.
In the instructions that came with my wheels it shows you how to install a tube and remove the valve, its sayes recommended for UST tyres, doesn't say you can't fit them.
Just go UST, these wheels are easy to seal up and hardly leak any air out over time, not like some wheels, that you need to pump up every ride.
normal tubes will fit a UST rim, but are more prone to pinch flats. The inner diameter of the tyre is ever-so-slightly smaller than that of the rim lip (where the bead sits), making for a tighter fit. The UST rim lip area is also narrower and deeper - these 2 factors mean it is easy for the bead to "slip" into the rim instead of sitting onto the lip as its supposed to.
That means:
1. need to be careful how you install the tube - it can get stuck between the rim and the tyre bead especially when you begin inflating. Classic pinch flat case.
2. it is also more difficult to get the bead of a non-UST tyre to sit right ALL AROUND the wheel. Even when fully inflated, the bead of my tyres sits slightly crooked (some areas properly seated, others not, dont forget this applies to BOTH sides of the wheel) so while my WHEEL spins true, my tyre does not.
/edit - one more thing, watch out for what type of valve is being used on the UST rim - I think they are usually sized for presta valves, which means you wont be able to fit a schraeder without some machining.
Thanks guys - much appreciated!