FJR Owners Forum banner
  • Hey Everyone! Enter your bike HERE to be a part of this months Bike of the Month Challenge!
1 - 20 of 27 Posts

·
Registered
Joined
·
7,364 Posts
Discussion Starter · #1 ·
I'm guilty for not checking the tire pressures before heading out today, but I had precious few hours to ride, so I gave the tires a quick squeeze, plugged the electric underwear and took off.

As soon as I cleared the driveway, I could tell there was something wrong. I could barely steer... but the tire didn't seem to show an abnormal bulge. So I turn back, get out the gauge. Back tire, normal. Front tire, 12.5 PSI! WTF!?

So I puffed it up to 50PSI, got out the soapy water... nothing, no bubbles. I reset the front pressure and headed out. All seemed normal, except for a surprise snowfall that left me crawling home behind a snowplow. (Dam winter) Seems to be holding pressure now.

Any ideas?

TIA



:)
 

·
Premium Member
Joined
·
2,982 Posts
Those V-Twins - mate, you gotta watch them. But I don't have any useful suggestions, except to replace the valve core. Maybe it isn't seating correctly.

I've had a tyre go down to low 30's from my usual 42, and then hold pressure fine after being taken back up to 42. Another of life's little mysteries: "Whare did the air go?" Trouble is, once it leaks out it just hides with all the other air out there - kinda just blends in. Makes it real hard to find again.
 

·
Registered
Joined
·
737 Posts
Liquid, if you're not able to find the leak, take the wheel and put it in your bathtub....it'll show up. :wink: Oh, it works better if you put water in the tub first. :D :D :D
 

·
Registered
Joined
·
372 Posts
PV=nRT
Liquid, when was the last time you checked your tire pressures? Honestly now. The cold weather ie. lower temperature has probably resulted in the basic physics lesson of reduced pressure.
I checked mine the other day and it was down 10psi due to temperature. And I would bet Minnesota is a helluvalot colder than Victoria BC.
 

·
Registered
Joined
·
7,364 Posts
Discussion Starter · #8 ·
fastwally said:
Pin hole in the rim?
That'd be a tuffy to find... warranty claim on a front Marchesini, woo hoo. :roll:

rad said:
A sign from the gods that motorcycles are not at their best in snow?
Smart a$$! :wink: :p

David1300 said:
Trouble is, once it leaks out it just hides with all the other air out there - kinda just blends in. Makes it real hard to find again.
Glad to hear it seems to have happened to someone else. I don't need the old air back, so if it floats your way, go ahead and keep it. I'm happy to relace it with new air... just as long as I know if there's a hole in the fence that needs mending. :lol: The valve core, yes. Good.

Petey said:
take the wheel and put it in your bathtub
Thanks, that'll be the next move. I've often got kids in the bubble baths, they shouldn't mind getting scrubbed next to a Pilot Power, right?

Rocketdoc said:
Liquid, when was the last time you checked your tire pressures? Honestly now. The cold weather ie. lower temperature has probably resulted in the basic physics lesson of reduced pressure.
3 weeks ago, narrowly warmer than today when I started. I've got the whole Delta-P thing (big effects on little helicopters, too) ... and there's so much salt dust all over the place, I wasn't going to push hard... but the rear tire was within 1 pound of where I keep it. This wouldn't account for being around 25 pounds low in the front only.

Bounce said:
mine are often lower than the last time checked if the temp gets cooler. even sitting idle for a week and the front can be 10+ lower than normal. each pre-ride gets a T-CLOCK
Ordinarily, I do check with a gauge before the ride. Today really proved you have NO IDEA what the pressure is from a 'thumb press' test. Because I DID do that. Only thing that tells you is if the tire's completely flat.

I know all tires seep a bit... especially tubed tires in the dirt bikes, they have to be aired up every week. And mountain bike tires... those bastages have to be topped off every ride, even from today to tomorrow. But modern tubeless tires usually hold very well, so often I'll forget about checking them on a consecutive days ride... not any more. ;)

Are there instances where there's just a tiny fold in the rubber along the bead that lets a pinch of air out, should I consider having the tire remounted before asking about checking for a leak in the wheel?

I'm going to pull the schrader valve(sp?) ... check for crud, air it back up and see what the pressure is in a couple of days. If it still leaks then it's off to the bathtub. Thanks guys.

:)
 

·
Registered
Joined
·
1,273 Posts
Take the front wheel off.

Get the solution of soapy water again.

Take the valve cap off, put a drop of water on top of the valve core.

Try and put some around the base of the valve and wiggle the valve about.

Lay the wheel flat this time, put solution around the rim/tyre bead and wait/watch for some time. Do the same other side.

It is always the case with alloy wheels that the internal rim corrodes, bubbles and pushes the tyre out slightly, causing the leak. Cure is to scrape off the corrosion and apply rubberised bead sealer.

Otherwise, the air fairy has been round and sucking your valve.....
 

·
Registered
Joined
·
7,364 Posts
Discussion Starter · #10 ·
Thanks Rabbit. Have you ever seen that corrosion thing on an almost new wheel?


:)
 

·
Registered
Joined
·
177 Posts
My rear rim leaked like a sieve from brand new, just could not be bothered getting it replaced. Found out later it was porous and leaking straight thru the metal. Lost 10lbs a week. I ended up fitting those little traffic light guages that told you at a glance what the pressure was. But then again, I always checked the pressures night before a long ride.
Just wonder what the wife would think if she caught me in the bath closely inspecting my BT020 for bubbles....mind boggles :mrgreen:

Malki
 

·
Registered
Joined
·
3,589 Posts
One word, sabotage. Was your honey-do list fully completed? Kids' allowance paid up? Just trying to help.... :p
 

·
Registered
Joined
·
1,273 Posts
@LS

Errrr - no. but, if you had a bad tyre bead (for example), I suppose water could have got in and corroded it fairly quickly, maybe, possibly.

Must have been the air fairy then.
 

·
Registered
Joined
·
7,364 Posts
Discussion Starter · #14 ·
malki said:
My rear rim leaked like a sieve from brand new, just could not be bothered getting it replaced. Found out later it was porous and leaking straight thru the metal. Lost 10lbs a week.
Yikes. That sounds too close. But I usually DO check the pressures, and it wasn't going down before. Was the air loss intermittent?

malki said:
Just wonder what the wife would think if she caught me in the bath closely inspecting my BT020 for bubbles....mind boggles :mrgreen:
LOL :lol:

20valves said:
One word, sabotage. Was your honey-do list fully completed? Kids' allowance paid up? Just trying to help....
All intriguing questions, but I think I'm quite securely in positive territory with all of the above... except my daughter's not getting a horse for Christmas. Hmmm.

Speaking of sabotage, perhaps the same disgruntled sod is responsible for shattering the 8-foot high window on the front of my office building... not a nice thing to arrive at the office to find. I've been scanning my mind for someone that's unhappy about something, and I can't figure. The union guys are all happy, the office girls are happy. There's one client's assistant that questioned me on an invoice and I had to destroy her argument, using her own emails against her... that's the only thing I can think of.

Perhaps it is all about the 'air fairy' Rabbit tells us of. Stole the air out of the tire, and then headed downtown for some good ol' fashioned air fairy vandalism. :lol:

...t's been a weird weekend. :shock:

:)
 

·
Registered
Joined
·
124 Posts
Could you get your mystery Air Fairy to send some of your clean and fresh air over to Southern England please where large swathes of the area are under thick black oily smoke from an oil depot fire. :wink:
 

·
Registered
Joined
·
234 Posts
Leaking rim?

Not a common problem on the FJR.
Pull it submerge it and see where its coming from.
FIRST! Make sure Its not a bad valve core.
Always run with valve stem caps.
 

·
Premium Member
Joined
·
2,982 Posts
Re: Leaking rim?

james1300 said:
Not a common problem on the FJR.
Pull it submerge it and see where its coming from.
This isn't on a FJR - Liquid's loins now wrap around a slinky Italian number. A step backward, IMHO, but when you are young, restless and fickle, this can happen. And then he finds her pneumatic attributes going flat under him - some unkind souls would say "serves him right"
 

·
Registered
Joined
·
7,364 Posts
Discussion Starter · #19 ·
Slinky Italian number indeed, but it's hard to say that the ST4S's Marchesini rims are a step backward. :wink: You'd have to give up some real cabbage to get them fitted on an FJR... oh, and don't they come standard on the R1 LE? I think the Ohlins suspenders that came stock on the Duc are the same as the stockers on the R1 LE, too. The hardware on that crazy Italian thing ain't too shabby.

No pressure lost in the last 24 hours... temps the same. Seems to me a leaky rim would leak all the time. :?

I have been running a few fire roads on the thing (100 pounds of steps backwards sure feels better on gravel roads ;) ), so I wonder if a piece of grit from the dirt roads found a spot to cause a little leak at the bead.

Still scratching my head.

I do always keep valve caps in place, BTW.


:)
 

·
Registered
Joined
·
3,589 Posts
Liquidsilver said:
I have been running a few fire roads on the thing
That's a great idea! How come I never think of stuff like that? Do you have a 21" Marchesini on the front? :p :D
 
1 - 20 of 27 Posts
Top