Newbie help - Tyres going flat ? Am i Doing something wrong

bilabonic

Hi All

After purchasing my first road bike with i and ONLY ridden once due to working away i came back to go for a nice ride in the sunshine. on getting home found both tyres flat, so pumped up tyres with track pump (first time dealt with presta valves). Front inflated fine, then went onto back and it seems to be leeking through the valve even when pumping and when i try to 'nip up' the screw after getting some pressure in and continues to deflate.

So i thought just unlucky/dodgy valve get new tube, checked the front and that had deflated withing 2 mins !!

Is this pure bad luck or am i doing something wrong, when i first had bike pumped both tyres upto about 110 with no prbs and went for 1 hour ride with no probs and now returned to this ?

Cheers

tenbar

Sometimes when pumping up tyres the valves can get "waggled" too much (either by heavy handedness or by too much sideways stress from the pumping operation) and this can cause a split at the point where the valve is welded to the inner tube. This could be the cause and is preventable by keeping the valve as straight as possible when pumping up the tyres.

bilabonic

Will have to remove tubes then and have a look, it seems to me that the leak from rear is coming directly out of the valve as if the vlave is not sealing,even if i move is side/side it expells air.

When pumping i am very carefull of movement and since its a track pump with tube there is no adverse force being put on the valves.

Gutted, only got cutlery drawer tools to remove the tyres as well....lol

tenbar

If there's no hole in the tube or in the valve/tube weld then it must be a loose valve or a defective one.