14

In case you really want to drill, the only thing you need is a 10mm drill bit, and a sandpaper to give a smooth finish. It is true that the rim gets weaker, and very narrow rims should not be drilled, but I have performed this enlargement a couple of times and rode the wheels some honest hundreds of km in every kind of terrain, with no problem. I did this ...


13

Drilling out your rims will reduce the strength of the rim and increase the likelihood of cutting the valve stem on your tube. For a few dollars you can buy two of these: This adapter threads onto a Presta valve and effectively turns it into a Schrader valve. Presta valve tubes are the same price and are as widely available as Schrader valve tubes, so you ...


10

My conclusion after many years of using not two, but three types of valves is that the best is the one that results most practical for you, acording to type of riding, type of pumping methods available and of course the type of bike/tire/rims you are using. Neither valve type is absolutely better than other, but one of them may result better for your ...


8

From these three, which one you have? Case ①: Schrader valve Check if the inner part (valve) is properly installed (tight enough). If is and still loose air — you need to change the valve or the inner tube, the problem is with one of them. Case ②: Presta valve You need to unlock the valve before pumping, or you will pump air only into you pumps' hose. ...


8

Your valve has slipped partially inside the hole in the rim where it exits. Normally it's on average about 1-1/2" outside the hole. You'll need to inspect the valve body to see if it's cut. You can't put a pump on it because the main body of the valve is stuck. First fix the valve body position, then inspect... Here's how to fix: Deflate the tire about 90%. ...


8

I would bet this is caused by a tire with rubber that got "old". This tends to happen to MTB tires that are repeatedly ridden on mud, and I had some tires with this behaviour before. The problem seems to be insuficcient friction between the rubber and the rim around the bead, specially on those tires with a material resembling fabric on that region (like it ...


7

Short answer, it's not common at all and probably wasn't like that when the bike was new. The valve that you need is determined by the rim rather than the bike. If the rim is drilled out with a big enough hole for a schrader valve, then that's what you should use. If a schrader valve doesn't fit through the valve hole, then you should use a tube with ...


7

Much of the drop you see will be due to the reconnection, not the disconnection. When you disconnect the pump you have 120psi in the tyre and the hose, gauge and a little bit of pump. This immediately drops to zero (as these are all gauge pressures). Most of the hissing you hear is this air leaving the system When you reconnect the 0 psi in the hose ...


7

I haven't come across this before but it's not right. It sounds like the valve coating is coming unstuck from the metal part of the valve. If that fails it would be quite likely to fail suddenly which could be painful. Time for a new tube


7

With MTB tires, there's really no issue in drilling out the valve hole to a larger size since the rims are so wide to begin with. You can do it yourself with a drill bit (3/8" or 10mm) or have your LBS do it. Sanding or reaming the hole afterwards is important, as well as making sure there aren't any sharp metal bits floating around afterwards that might ...


7

I do this all the time, basically use the presta nut on the inner side to avoid the tube getting "pinched" in the extra space, then if you can find another presta nut, screw that one to the outside where it's supposed to be. Works like a charm.


6

Assuming the issue is getting the pump head to lock on the valve. Your tube has shifted and now the valve looks really short. You'll have to deflate the tube completely and move the tire around to wiggle it valve to a straight position. The pump should lock on to the valve without a problem once it sticks out far enough.


5

Sounds like the valve has stuck shut, this can happen if the rubber seal at the base of the valve swells up. If the valve core is replaceable just get the appropriate valve tool and a replacement core, both are really cheap. Otherwise its likely to require a replacement tube.


5

I have a Topeak "Road Morph" mini pump on my bike, and the pressure gauge on that is at best a distraction. The display is a bit of plastic sliding in a tube, so there's a lot of friction and that makes the pressure reading unreliable. It can stick anywhere, but usually it reads low, like yours does. That makes it useless for anything other than "is there ...


5

Yes, very nearly all, if not all shock pumps certainly do use a schrader valve.


4

The tire slipping on the rim is generally a sign of an underinflated tire. What sort of pressure are you running in the tires? Otherwise, it could be that that old rim is coated with some substance that makes the tire slip. Or it could be that the tire itself is old and hardened to where rubber does not grip the rim well.


4

Why not? The bike will roll anyway. You would need two pump heads or an adapter to pump both tires, but other than that, it will work just fine.


4

The cheapest solution is to try and remove the burrs or sharp edges that are cutting the tube. This can be done with a small file or a piece of emery cloth cut into a small strip and pushed through the hole. If the rim is double walled it will be difficult to get at the inner edges. The alternative is to purchase a set of schrader to presta adapter sleeves. ...


4

I know it's normal to lose a bit of air when getting the pump off but I'm not sure about this The air you lose when taking the pump off should be just a very brief hiss. And, actually, it's mostly air coming out of the pump, not out of the tyre. You shouldn't lose any significant amount of pressure when taking the pump off. The only thing I can think of to ...


3

Try covering the hole from the inside with gorilla tape and opening the hole back up with an x cut pattern like you would with ghetto tubeless.


3

My current pump (a floor pump) clamps onto the valve with a clamp instead of threading it on. I can very quickly release it. This could be at the expense of not being able to pump it to 120 PSI (which I don't need). It may be possible to adjust the pin in the business end of the pump so that it stops pressing on your valve sooner when you unscrew it; that ...


3

Tubes may be cheap, but good luck filling a presta valve when you are on the road in the USA. NO gas station has presta chucks. And if you are living in the USA, it's a 3/8 inch drill bit to convert to schrader valve. I have yet to see anyone have a wheel collapse due to converting to schrader valves. The bike shops warn against it because they gotta sell ...


3

It depends on the width of the rim, and how it's constructed. If the rim is over about 32mm (about 1.25", measured from inside to inside) then it probably has sufficient "meat" in the rim that drilling will not significantly weaken it. But of course it would be silly to do this simply because you have a Scharader tube -- tubes are cheap.


3

Actually, correct drill bit size is 21/64", not 3/8" http://sheldonbrown.com/gloss_sa-o.html - search for Schrader


3

A Schrader valve has an external width of 7.7mm per the specification. The number written on your valve refers to this fact. Source: https://en.wikipedia.org/wiki/Schrader_valve#Dimensions


2

Ripping off the valve is a pretty rare occurence I think. If you manage to pull the valve off or even just spring a leak while removing the chuck then the inside of the rim (where the root of valve connects to the innertube and hits the inside of the rim) could be too sharp or the protective rim tape could be damaged or mis-aligned. This is the first thing I'...


2

Well, you were quite right Chris H - I went out the next day to look at it, the tyre was flat, and the metal Schrader valve was hanging out of the tube at a crazy angle with the rubber bit that goes up the side of the valve split right open. So I replaced the tube - a 20in Kenda 1 3/8 - with a Raleigh one. Nominally the same size, but as you can see from ...


2

Sadly no - that short hose would have been used on an old-school frame pump, and yes, it would have been stored in the handle. The host/pump thread is not the same size or pitch as a schrader. The threads are not opposites, so that hose won't go into a schrader chuck. Compare the end with these adapters - see how the brassy one looks like another schrader ...


2

There's no mechanical reason why you can't have one of each. The disadvantages are purely practical. You need a pump that can deal with both valve types, or two pumps, or to mess about with adaptors. You need two kinds of spare tubes at home. Most people who cycle longer distances bring a spare inner tube with them because it's much faster to replace the ...


1

My hybrid currently does, and it's not a problem. I'm switching over to presta tubes so that the same spares fit that and my tourer. That way I don't have to stock so many types of tube, especially in my commuting pannier. The presta should be used with a spacer of some sort. I prefer a rubber grommet as the plastic parts sometimes sold for the purpose ...


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