Bicycle Mechanics - How do I get the correct tube size?

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PDA
10below
04-18-09, 04:54 PM
I have 700 x 25c tires. The tube I bought is of the presta variety and the size of the tube is 700 x 25/32c... I'm guessing this tube will work and would work on a bike that is 700 x 32c... am I on the right track? How important is it for the valve steam to be snug in the valve hole of the rim? The original tube was a schrader valve and was more round in diameter and fit more snuggley in the hole. This presta valve is slimer and not as tight of a fit....

any help is appreciated...

Al1943
04-18-09, 04:59 PM
You need an adapter bushing to go in the bigger hole. This is important.
You do have the correct size tube.
You'll need a floor pump with a presta type chuck head. Many will work both ways.

Al
10below
04-18-09, 05:04 PM
Ill be sure to get an adapter bushing. I saw that I could use a presta valve adapter and screw it on directly to the valve. would this be sufficient?

operator
04-18-09, 05:07 PM
Ill be sure to get an adapter bushing. I saw that I could use a presta valve adapter and screw it on directly to the valve. would this be sufficient?

No.

The adapter goes at the top of the valve to convert it, it does nothing for the hole in the rim which is actuallythe problem. Go buy the rubber grommets or the brash bushings available. Or buy a shcraeder tube.