Replacement Angled Valve Stems:
One of the easier changes to bikes, in terms of adding or checking air, is to add angled valve stems.
I'm talking about permanently mounted replacement valve stems, not the temporary add-on kinds (more about which in a minute). The permanent ones come in, um. let's call them regular sizes, and low-profile designs.
An example of the larger size is this one available at Sound Rider:
An example of the lower profile design are these similar versions from Sound Rider and then Kurvey Girl:
Incidentally, both Sound Rider and Kurvey Girl are reputable outfits, been around for years, and I've done business with both. There are, of course, other sources for similar or identical replacement stems.
For the 2008 Exec I purchased last summer, I ordered the pair from Kurvey Girl. They are sitting on a shelf, awaiting my taking the scoot to a shop for a new set of tires.
Valve Stems, Which Size?:
As that Sound Rider page above (the 84-degree one) notes, there are two common rim hole sizes for bikes. Most bikes have 11.3mm holes, and the exceptions (the ones that use 8.3mm holes) are noted. Our Suzooks use the larger size; I also own a Victory with the smaller size.
Valve Stems, Which Way?:
Unless you do your own tire changes, make sure you specify the direction you want the shop to mount your replacements. That is, don't assume that there's a standard way of doing things.
Everyone I know with bikes prefers the opening to point to the right side of a bike. (And the standard for "right" and "left" are as someone is sitting on a bike.) This makes the valve opening more available when a bike is on the sidestand.
I am a big fan of extension hoses. I've purchased, in the last few years, about a half-dozen of the "10 Inch Mini-Air Compressor Hose Extension" from Stop & Go:
Some of these are for my own use: I keep one with each bike, under the seat or in a saddlebag, and one in the garage. And I've given away a couple.
One of the temporary right-angle add-ons mentioned earlier in this thread is the "Oxford Valve Adapter 90 Degree" one:
Sound Rider sells a similar temporary-use one:
And Sound Rider also sells a clip-on version:
The problem I have with either kind of temporary, use-only-while-filling-or-checking-air, add-on valve gizmos is that they don't provide enough work room, not enough relief.
If you're working on a front wheel, much of this is irrelevant. However, if you're working on a rear wheel, you almost have to get way down on the ground, especially when dealing with bikes with saddlebags still on (of which I've had two).
My point is that if you're going to screw or clip something onto the rear valve, why not also give yourself more room to work, more room to move around?
It's not as if you merely put a right-angle extension on a valve, and you're done. You still have to hook up a pump, and maybe remove that to do a pressure check after pumping, rinse and repeat. So I like to hook up an extension hose -- particularly on the back tire -- and then work from a sitting position on a roller stool. When I'm completely done messing with the tire, I may have to get down on the ground again (especially with a bagger) one more time.
Screw-On or Clip-On?:
This Stop & Go extension above is a screw-on type, with a nice large knurled outer surface to grasp. Stop & Go also sells a clip-on version (what they call a "quick release"):
To each his or her own, but I prefer the security of the screw-on kind.
Some people prefer clip-on connectors, squeeze and push on, squeeze and pull off. A lot of small air pumps come with that sort of end, but I find that they're only theoretically easier to work with. In actual use, if you don't make a perfect connection when you let go of the lever thingy, the end will pop off on its own, or the mechanism will not adequately depress the Schrader valve, and that sort of thing. That's why I like the screw-on kind, even at the expense of little air loss on removal; as I said, the Stop & Go hose provides a nice grip, and if you don't dawdle, the air loss will be negligible.
The editor at webBikeWorld posted this video recently, as part of a review of a small pump:
This does not involve the Stop & Go extension hose, but the end of the hose on the pump that he's demonstrating has a similar mechanism. And he comes up with a loss of less than 1/4 PSI, so it's all good, as they say.
And the manufacturer's rep has a comment on the video, similar to what I just said: "... after years of building pumps with the flip type quick release fittings, I was largely dissatisfied and moved to the screw on 'zero loss' fittings."
For garage use, for the bikes, I often use this 12-volt model from Harbor Freight:
I have a HF store nearby, and with coupons and sales, it's a very nice pump for the money. I keep one of those Stop & Go extension hoses affixed to the end of the included hose.
For carrying on-bike, I have a Stop & Go pump:
For the other bike, I carry a slightly larger, slightly older, version of the MotoPump shown in that YouTube video above:
In the old days, I used to use reasonable quality dial gauges. Over the last decade or so, I switched to digital gauges. I haven't used "pencil-type" gauges in almost half a century (I'm 68, and I pretty much disregard the gauges that are built into many pumps (I'm OCD with tire pressures).
Here's a pic of some of my gauges:
My current favorite, especially when working with car tires, is K-Tool's KTI-89001:
This has a nicely angled large chuck at the end, and the gauge is accurate and easy to read, and has a nice add-air lever. It's available at Amazon and maybe a few other places for about $65:
This is appropriate for a regular big ol' compressor, not a small 12-volt one.
When working with bikes, I sometimes use the KTI-89001. Since that large, esay-to-grip chuck is generally too big for the confines of bike wheels, I usually replace that chuck with Motion Pro's "Pro Fill Air Chuck":
The Pro Fill has a built-in mechanism, such that swiveling it (which requires a fair amount of oomph) will change the angle of this chuck in major ways. This is not for use -- as I hope I conveyed -- for an extension hose attached to the rear wheel, but if you're dealing with the front tire, with some open space, this combination works nicely.
Last, one way to make at least checking air much easier is use a tire pressure management system (TPMS). I was surprised at how little air loss I have, once I started measuring it with a TPMS. Of course, you get changes that are the result of day-to-day changes in ambient temperatures (see Gay-Lussac's, Charles', or Boyle's law). But these are generally not significant enough to warrant airing or subtracting air, at least in my opinion.
I reviewed the Doran 360M TPMS about three years ago for webBikeWorld:
This is a dedicated, on-bike, system. I have this on my 2012 Victory, and like it, but have now become less enamored of it, given how often the sensors have to be replaced, and how expensive they are.
I'm thinking of getting the FOBO Bike system for my 2008 Exec:
The FOBO is cheaper, and doesn't require any dedicated module. It does require a smartphone. Also, this is more appropriate for checking pressures before you head out, as opposed to also giving you real-time warnings about a nail you just picked up; for that, the Doran is a better system. I suppose you could always mount your phone in a RAM cradle or suchlike on the bike, but I don't find that to be nearly as convenient as the Doran's permanently mounted module (and most phones aren't waterproof, and that's one more thing you have to deal with after each lunch or rest stop).
Note that I'm not positive that externally mounted TPMS sensors -- the kind that screw onto a valve stem (and make that a metal valve stem, not rubber!) -- will fit on rims to which a low-profile valve stem has been mounted (such as the Sound Rider and Kurvey Girl items I cited earlier). That is, I'm not sure there's enough clearance between the end of the valve stem and the rim proper. I may find out in a few months.
TPMS is perhaps a topic best left to another time. My point for now is that it's certainly an easy way to check air pressure, i.e., look at some screen.
I hope you find some of this useful.