Problem checking rear tire pressure

Am I the only one who has trouble checking the rear tire pressure on my ST13? I have several tire gauges and none of them seem to be able to get a good reading since the valve stem is so close to the wheel. I'm losing pressure and I can't find any nails or anything else so I'm guessing that I have a bad valve stem or valve stem core. I have a brand new 45 degree valve stem left over from my Concours days that I'm going to have installed. The tire is almost brand new so I really don't want to replace it unless I have no choice. Also I really want to change over to the Michelins when this Dunlop Sportmax set starts to wear out. I've read two opposing reviews. One reviewer stated that the PR3 gave him better traction than the PR4 and one said the opposite. Does anyone have any suggestions or experience with the Michelins? Also, has anyone tried a Michelin on the rear and a Dunlop on the front? I've never mixed tires like that but I've seen others get away with it. I'm a little leery about breaking down a nearly new tire but I've done it before with no problem, although that was with a spoke wheel and tube.

A lot of us have replaced the rubber valve stems with right-angle stems that make filling the tires and life much easier.

There are also right-angle temporary extenders that are placed on the stems for filling and then removed immediately afterwards. Leaving them on would eventually damage them when centripetal force and their extra weight weaken the rubber stems.

Here's what I use and where I got 'em:
https://www.st-owners.com/forums/showthread.php?117842-90-Degree-Angled-Valve-Stems-Black-Red-Blue-Gold-and-Silver

There are cheaper alternative but I like these for the light weight good looks and compact size.

If you go the 90 degree metal stem route make sure the stems are mounted pointing to the right (starboard). That makes them easier to reach when the bike is on the center stand.

My theory always is run 'em til they're done......liking the Bridgestone t3o gts a lot, but tires are like oil....everyone has a favorite....spray soapy water on your tire until you find the leak....then run it til it's wore out.......have fun, ride safe............ff

The angled valve stems (Airete) help. Also, removing the right saddlebag gives you much easier access. (You can rotate the tire to move the stem to nine o'clock.) It only takes a moment to remove the bag, and allows you to avoid crawling around on the ground.

If your tire pressure gauge has a hose on it, one of the holes in the hub actually lines up so you can run the hose thru the center of the hub and get a good reading. having said that I replaced mine with the angle valve stems as wee which make it really simple. As roginoz said, remove the right bag and you barely have to bend over.

Mix a bit of dish soap with some water and spray the mix on your wheel around the valve stem. Bubbles will indicate a leak. (You can buy similar stuff at plumbing supply houses - they use it to find gas leaks). If nothing shows up, spray the stuff around the wheel at the bead. Sooner or later you will find the leak. And, if not, you can rinse with water and you've cleaned your wheels!

billy396 said:

Am I the only one who has trouble checking the rear tire pressure on my ST13?

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You're certainly not the only one. I HATE topping off the rear because there's not enough clearance. I have a set of angled stems in house, waiting for the next tire change to get installed.

I have several tire gauges and none of them seem to be able to get a good reading since the valve stem is so close to the wheel.

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I found an electronic gauge with a 90-degree elbow at the input end, which at least makes checking the pressure much easier.

I'm losing pressure and I can't find any nails or anything else so I'm guessing that I have a bad valve stem or valve stem core.

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+1 on your experience
+1 also on someone else's suggestion that it may be a gradual leak around the bead as well as or instead of a bad valve stem / core. I'm told by a friend in a position to know that if the rim was not thoroughly wire-brushed at the last change the tire may not have seated and sealed entirely as it ought to have done. But the abuse that my rear stem takes when I'm inflating the tire makes me very suspicious of its integrity. I'll be doing both the wire brush treatment and stem-ectomy next time the rear tire is changed (hopefully that will need to be done midway through this summer if my riding dreams pan out).

Good luck finding and fixing what is a most aggravating issue.

I point the rear Ariete to the right and the front one to the left. Being right handed, it's easier.

DeanR said:

I point the rear Ariete to the right and the front one to the left. Being right handed, it's easier.

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I do the same thing.

A big thank you to everyone who has taken the time to help an ST13 newbie. I've been riding for over 40 years and this bike has literally put the fun back into riding for me. My last bike was a 2008 Harley Super Glide (my 5th and LAST Harley), before that I had a Concours 1000 which was a scary fast, fun bike but I just couldn't get past the vibration in the grips. I've owned every brand of Japanese bike, 5 Harleys, a Triumph and a Hodaka back in the early 70's. How many people remember the Hodaka Super Rat? Overall, one of the most enjoyable bikes that I've owned was a 1979 Yamaha XS100 Special. I rode that thing on a daily basis around town in addition to a non-stop ride from Sarasota, FL to Cincinnati, OH. I miss those good old days when my body would allow me to ride virtually non-stop for as long as I wanted. Now I have a twice-broken back and arthritis in every joint so my long road trips are pretty much over. Again, I must comment on how much the ST1300 has put the FUN back into riding for me. I really like this bike (and I've had at least 18 bikes to compare it to). As of 2010, I still had a small collection of 5 bikes including a Gold Wing Aspencade, a Ninja 750R, 2 Sportsters and a '78 Suzuki GS750 (my 4th GS750). As of last week I've finally pared my collection down to just the ST13 and I love having room in my garage again. I know that this is a complex bike and that I have much to learn, but I'm hoping it's as dependable as that Gold Wing was. Also, I ended up replacing my rear tire with another Dunlop Sportmax. I found a 45 degree valve stem that I had left over from the Concours, so that's one problem solved. Also, I'd like to give a big thanks to Seth Laam, who did a fantastic job rebuilding and recovering my stock seat at a very reasonable price. I wouldn't hesitate to recommend his handiwork to anyone who wants to have a better seat without paying for a Day-Long (which I almost did). Sorry for the long-winded post but I'm a little surprised at this bike. It's not 100% perfect, but it is FUN.

Good to hear your liking the bike! Remember the Hodakas well. SuperRat was the 90 on steroids, with a little better suspension. A light riding of the rear brake, and either one could be rode off into sunset on rear wheel. The Combat-Wombat was even better yet.

Did you try winding it up to say 20mph and stomping on the rear break with the clutch pull in.
I'd bet that's the 1st thing they try. If that doesn't do it in a few attempts it's time to pull the cover and pry them apart.
+1 let us know what they find.

I remember buying the book "learn how to wheelie" because it had a hodaka on the cover!
I started with an Ace 90, then a 100b+ then a super rat, a 125 wombat, then a combat wombat, then a couple of the orange tanked versions...by the rat was my favorite! Used to beat my neighbors HD baja 100..

+1 on the arietes. In the mean time spray a little windex on the stem and gently wiggle it. If you see any bubbles look for cracks and replace it now. Same for the tires and bead sometimes it's hard to see a nail etc if the head has been worn off. Easy enough to screw another core in and use a metal cap with a seal.

If the tire is trash I wouldn't worry about running 2 brands. Is a dunflop sportmax rated for the st, is it a roadsmart?

.02 is you have a dunlop I wouldn't worry about a pr3 vs 4
The 2s and 3s are ok haven't gotten to a 4 yet. They go quick after they hit the wear bars particularly the rear and it'll step out a little easier in the wet then. When they have tread they're quite good in the wet.

I can't speak for the st. But on my f4i I have had the michelin power, then road3, and now the road 4 gt the .gt is a harder compound for 2 up or heavy luggage of which I have both. I have loved them all. I've ridden in massive downpours and never had an issue with traction. As soon as the stock tires wear on the st, I'm putting the pilot road 4's on.

My ears are still ringing from the pleasant scream of the Hodaka. Hodaka, cz, Greeves All great 60 and 70's dirt bikes.

Anyway I learned all to well about filling a tire on the road with a small leak when no one has a right angle air chuck. A lot of driving from station to station to find someone to fill the tire. I even had a compressor on the bike and had to modify the clamp to fit on the rear air inlet. After I got back I put a right angle air valve on the rear tire. Now no more problems.

Thanks to all. It was some kind of staple or steel something that was virtually invisible. I went ahead and replaced the rear, as I regularly use plugs on car tires but I don't ride my bike like I drive my car, and theres also not as much right out there on the line if worse goes to worse. This bike has really put the fun back into riding for me and I push the limits more than I should, so I'd rather spend the money on a new tire. Thanks again. BTW, I found a set of angled valve stems left over from my last Connie and that problem is solved as well.

Igofar said:

I remember buying the book "learn how to wheelie" because it had a hodaka on the cover!
I started with an Ace 90, then a 100b+ then a super rat, a 125 wombat, then a combat wombat, then a couple of the orange tanked versions...by the rat was my favorite! Used to beat my neighbors HD baja 100..

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Back in the early 70's I rode trails with a friend who had a Super Rat an that thing was a blast. I miss those days.

There are a number of digital pressure gauges available having right angle fittings. I got a really nice one from Roadcrafter. Filling the tire, however, can be a problem, of course.

I have a right angle Accutire gauge & a right angle filler valve on the airhose.

The tire gauge is quite old...I'm not sure they still make them.