How to inflate a tire with a Presta valve?
My new bike has these thin tires with a type of valve I haven't usedbefore. I searched online and found out it's called a Presta valve, and it's pretty common and popular. I'm finding it annoying and fiddly and don't know how to use it properly. I have a floor pump, and I know the valves and pump are fine, because the guy in the shop had no trouble using the same one. But after reading online and watching YouTube videos I still can't figure out how to do it properly!
Here's what I'm trying:
- Rotate wheel so that the pump can comfortably reach the valve (guides online say the valve should be at 12 o'clock position, but I can't do that because the hose on the pump isn't long enough)
- Remove valve cap, unscrew thingy in valve, and tap it a little - a jet of air shoots out. OK.
- Push pump onto valve. This is where I get into trouble...
I can't seem to get the attachment onto the valve in the right way. I'm pushing it on with the elbow lever thingy down, and then pulling the lever up as you can see in the pictures, to make the attachment grip onto the valve.
Now, either it flops around loose and leaks air out the sides (when I push it on gently), or sometimes it goes on but then the tire doesn't seem to inflate any, the pump just gets stiff really quickly as if the valve was blocked - then I remove the attachment and it goes pffffft like all the pressure was just backed up in the hose and not actually going into the tire.
I was able to pump up the tire eventually, but it took me about an hour of stuffing around and my "project manager" got angry, because I was supposed to be in the kitchen making her a salad, not mucking around in the garage.
The time I got it on properly I had to deflate the tire completely, and even then it was difficult because with the tire completely deflated the stem of the valve just pushed into the rim. Surely this is not normal? What's the trick of attaching the darned thing?
Also, how can I just check the pressure? When I attach the thing I expect the guage to jump up and show me what pressure it's at, but it just stays at 0. The tires say on the side to inflate to 110 psi (7.5 atm), but my pump only goes up to 100.
I always put the valve at 6 o'clock (closest to the floor) when filling. That way when you push the pump head onto the valve, the bike doesn't go anywhere. With my pump, I have to get the valve quite deep into the head and it's difficult to do this in any position other than having the valve at the floor.
Looking at the picture, it seems you may not have enough of the stem protruding to actually connect it properly to the pump head. I have similar rims on one of my bikes, and I ended up getting a valve adapter as @Zippy mentioned below instead of buying longer stems, as they cost more than the shorter stems, and the adapters are quite cheap anyway (75 cents at my local bike store).
@kibbee - I like the stem high, so I don't need to bend over as far. But I don't have aero rims.
Presta valves are typically used in cases where a higher tire pressure is required - the pump you are using may not be able to handle pumping a tire up to 110 PSI. (or the guage may simply not show the pressure, in which case you may need to be careful of a blowout.)
Presta valves are an invention of the devil. I have bee using them for years and still have trouble. They are fragile and must be used just so.
Those valve stems are too short for those deep deep rims you've got on there. You can tell just from the photos that the valve stem isn't sticking out far enough from the rim for the pump to fit all the way on it. Hence, it's not contacting the valve enough for you to inflate your tires.
You're absolutely right. There should also be a jam nut to keep that stem from wiggling around when you try to get the pump head seated.
Yep, I think you've got it. Who supplied those wheels with too-short stems?? (I've had the problem that it's hard to find shorter stems for my regular box rims anymore -- surprised that this situation would ever occur.)
I've done this before by accident - you need to get tube with a 60 mm valve instead of a 42 mm value
It's possible the bike shop got it to inflate by pressing into the flat tyre with finger before inflating to support the valve stem (doing the job of the nut) whilst shoving on the pump. Pumps differ in the clearance/depth of stem they need pushed inside to get a working connection, so yours might be unfavourable to this combination. Removing the nut lets you get another 3mm of stem inside the connector which can be enough to get it inflated. I've seen shops chuck the nut (like this) when they've supplied the wrong part! Ultimately, chuck the inner tubes for 60mm versions.