25c tire on a A719 rim

[velosam]

My marathons are getting scrappy and I have not got a replacement and need a tire for Monday.  Can I fit a 25c durano on the rim?

I can't see any specific size on the rim or the invoice.

Thanks

[mattc]

The Mavic site is full of useful info of this sort - try there?

(as it happens, I believe I rode nearly 1000 miles of german audax with the same combination you describe - albeit a lighter tyre, still 25c. Purely cos that was the rim that was attached to my only dyno-hub!)

[velosam]

Sorry it just occurred me to check and they recommend a minimum of a 28, so it may not be wise to run the 25 for commuting.

[Brucey]

some manufacturers of rims with a similar internal width do allow 25mm tyres on their rims.  It is something of a modern fashion in some circles.  Myself, I'm not right keen on a tyre that narrow on that sort of rim, but I'd use it as a front tyre for a while, if I had nothing else.

cheers

[velosam]

cheers will give it a shot till I get a new front

[Banjo]

I ran durano plus 25c on those rims for about 2000 miles without any problems.

[rogerzilla]

Observe the maximum pressure and err on the cautious side.  Wired-on Duranos will blow off at about 120psi even on narrow rims, and I think they are only rated for about 110 or 115psi.  A narrow tyre on a wide rim increases the risk of it blowing off.  I wouldn't go higher than 90psi on a wide rim, which may not be enough depending on your weight and the number of sharp-edged potholes in your area.

[mattc]

Are people still riding on tyres over 110psi on UK roads?!?

 

Meanwhile, re this:

some manufacturers of rims with a similar internal width do allow 25mm tyres on their rims.  It is something of a modern fashion in some circles.

There's a slightly interesting artlcile in current Cyclist mag - some design engineer states that rims that sit "proud" of the tyre (i.e. their outer width is wider than the inflated width of the rubber) give a lot less drag than traditional arrangements. So that was his excuse for putting wide rims and 23mm tyres on the new bike.

How many riders this will *actually* benefit is perhaps less certain ...

[zigzag]

there are wind tunnel tests that show the most aerodynamic rim/tyre combo is when a rim is 5% wider than a tyre. practically though, such setup makes the rim vulnerable to scratches from the curbs etc.

to answer the original question - i've ran a719 rims on my hack bike for a decade, always with a 25mm tyre, never had any problem. i also have 25mm tyres on 21c internal rims at around 80psi, also no problem.