New answers tagged

1

Since the Presta valve closes after each pump-stroke the pressure in the hose is equal to the pressure in the inner tube. The chuck does not mechanically open the valve as with Schrader (car-type) valves. You will have to overcome this pressure with the following pump-stroke to get more air into the tube. The maximum pressure obtained in the inner tube ...


2

A cheap solution: regular Duc-tape works really well. Put a separate piece over each hole, in case you need to replace a spoke. I've also used it to tape the rim tape directly to the wheel when an old one broke.


0

Presta Valves, or any valve for that matter do not leak after you have taken the pump head off. The valve should automatically close even without you having to screw down the valve. Doing that only applies pressure on the valve to reduce leakage over time even further. If the valve keeps leaking till you screw it down means that there is some damage in the ...


6

In my experience there is always some air loss when you remove the pump from a Presta valve, but that air is lost from the pump side of the valve. It's easier to see with a floor pump, since there's the hose to hold air. In a floor pump there's a check valve is at the pump end of that hose, and that will hold the air in the hose at high pressure even after ...


0

You should never exceed the maximum pressure that the tire says. But the tube shouldn't leak any air when the Presta core is unscrewed before or after you connect the pump; at that point you should have to push on the little knob that you unscrew to make air come out. I did some web searching, and your problem with air leaking out of the valve seems ...


-2

Those are three different sizing standards First one is 20mm inner tube diameter and 622-630mm inner wheel diameter Second one is inner wheel diameter of 27inches and inner tube diameter of 3/4 - 1 inch Third is rather more confusing. The 20 and 25 refer to the inner diameter of the tube in mm. The 700c is a measure of the diameter of the wheel but c is ...


10

I figured out a solution. The thing that is supposed to stop the inner tube from expanding into spoke holes is called a rim tape. The tape that came with the bike is really flimsy. I'll purchase and apply a high pressure rim tape. Hopefully that would fix the problem. Update: I've decided to go for a cotton rim tape as they're more durable than rubber ...


1

Did you inflate the tube off the rim or without a tyre? they stretch when inflated naked. Read the tube side it might be a 27.5 in the wrong box.


0

It will fit once its partially inflated. You need a 26 inch tube,with a range 26xa - b where a<= 1.95 and b>=1.95. Though, you could likely use a 26x2.00 tube just fine.


-1

Using the scraping tool or sandpaper to abrade the patch area may also leave the tube thinner. When inflated the thinner area stretches and may allow air to leak. You might have to stick the (temporarily) inflated tube under water to find these tiny leaks. Scrape sparingly, and the tube may still have plenty of life left. I am still riding a tube with six ...


1

As well as checking for debris in the tyres, applying the patch properly etc., you need to be careful not to give yourself a "pinch flat" when you put the tyre back on the rim. This is caused when you trap the tube between the tyre and the rim, putting a fresh hole in your recently repaired tube.


-3

In short: Patching a tyre is only temporary and should only be used to get back home after which it should be replaced. Long Version: There are many reasons why patch may fail. Some of which may include the adhesive and rubber patch quality as these may be very cheap patches. I generally never use any of the cheap patches that you can get out of the dollar/...


6

It looks as though you're confused about the range of allowed tyres on the rim vs the tube. What connects the two is the size of the tyre you actually have. There are two independent ranges. The rim is rated to take tyres in the range 28 to 38mm wide. Your tyre will be an exact size, and ideally should be within that range. You can measure the width or ...



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