Tire valves... [Archive] - Motorcyclist Café

Acacia

02-11-2006, 10:27 AM

When last did you check them?

A few weeks ago I replaced my tires. Inserted new valves too. Today went to check pressures in prep for a ride. Front down a few pounds. Put a little air in - and checked the valve for leaks- something I dont do often - and it was leaking - just a little!!! WOW!

Fortunate that the essential steel cap and seal is in good conditon or on the previous ride last week I might have been in trouble.

We take those valves for granted.

BobFV1

02-11-2006, 10:58 AM

geechie

02-11-2006, 03:15 PM

I spit on 'em. A generous dollop of slobber will tell the tale.

But back to the original post: Are you talking about replacing the valve core? Or the whole stem.

George

Acacia

02-11-2006, 07:29 PM

A method is as George says - I am not sure what he means by 'generous' - enough to cover the top - any leaks and it will bubble. Soapy water works/liquid soap if you dont want to slobber all over the bike.

One has several fix options. You can buy a tool that you can re-seat the valve core with. You can also replace the valve itself with a new one- which I did. It is prudent to change out the whole stem from time to time - something I have noticed motorcycle tyre change places dont do too often.

Make sure that you have a metal cap with a good seal in it. The plastic dust caps are just that. Some are of the opinion that at high speed there could be leaks through the valve due to it being directly in the cyntrifical rotation of the wheel.

BobFV1

02-11-2006, 08:31 PM

Hi guys -

I'm with you on the using metal caps part, and on tightening them pretty well with my fingers. I know the spit and soap tricks for testing the valve stem, but I would never think of using them unless I had some reason to believe they were bad, like more than the usual air loss and no sign of tire damage.

I always keep at least one cap with a core tool built in to the other end of it, in case that little bugger loosens up out on the road. Saves me having to carry a separate core tool in my kit. :icon_wink:

R4R&R

02-12-2006, 11:03 AM

You know, I haven't changed my valve stems in the last few tire changes (actually, since I've been doing my own tires). I need to buy a few of those nice metal ones, you know, that turn 90 degrees for ease of inflation/checking.

DarthRider

02-12-2006, 11:17 AM

Can't add much...but I will anyway!
Totally agree it is important to change valve stems (entire valve) every so often, maybe every 2-3 tire changes. Discount Tire Co. changes them with every tire change. Good preventive maintenance.
It is a good time to switch to right angle valves...very convenient. They are not real hard to find...a Triumph dealer will have them.
A valve core seat can lift at hi-speed resulting in air loss through a crappy valve cap. Tech inspection at Bonneville removes the valve and inspects for a viable rubber seal.
This stuff is so easy & cheap there's not much excuse for even having a problem...except damage of course.

Dave

Bill

02-12-2006, 12:00 PM

John, check with the adds..the right hand stem should only be used for checking air or adding air -NOT LEAVING IT ATTACHED WHILE RIDING.

"You know, I haven't changed my valve stems in the last few tire changes (actually, since I've been doing my own tires). I need to buy a few of those nice metal ones, you know, that turn 90 degrees for ease of inflation/checking.
__________________
John
'04 R1150RA
Itchin' for a ride........"

BobFV1

02-12-2006, 12:08 PM

John, check with the adds..the right hand stem should only be used for checking air or adding air -NOT LEAVING IT ATTACHED WHILE RIDING.

Bill - That is true for the 90 degree valve stem extenders they sell as after-markets to help you fill BMW tires (I picked one up from BMW of Santa Cruz), but you can also get an actual valve stem which is bent at 90 degrees and goes through the rim like a regular valve stem - I have one on the fron of my Ducati, I think is is stock. You have to make sure, when using these, that it doesn't affect your wheel balance - so if you change to the 90 degree stems you need to rebalance.

Acacia

02-27-2006, 02:03 PM

I learned something more about tire valves this WE.

The RED colored valve seat seal is preferred to the Black. A higher reliability silicone seat and the valves have a stronger spring to resist hi-speed centrifugal forces .

Arby

02-27-2006, 05:18 PM

I owned and operated, and worked on trucks for 40 years. From experience I can tell you that flat tires often show up AFTER they've been aired up. It only takes the smallest amount of trash to cause a leaky stem.

Always use the spit/soapy water test after airing up the tires,or even after just checking them. I'm hard of hearing, so I wantta see that they're not leaking.

I learned this the hard way.

Arby
(Bob)

R4R&R

03-05-2006, 05:09 PM

Well I just got done changing my rear tire and I ordered those 90 degree valvel stems to change out while I was at it. Bad news - They didn't fit. The o-ring on the new valve stem actually fit into the hole on the wheel which did not allow it to make a good seal. And to top it off, The tip of the stem was too close to the wheel and actually broke off while I was trying to seat the bead. So now I new a new rubber valve stem in place. Oh well.

Acacia

03-07-2006, 08:08 AM

Hoon,

Eventually, here is Michelin's answer back to me;

"I mount my own tires. Other makes of tire have colored marks indicating the tires heavy spot - usually red dots. The pilot road I have does not have that. How do Michelin mark their tires?

The Michelin Motorcycle tires do not come with mounting dots. Any
marking is either for quality control or an inventory devise. There is no
relationship with these marks and mounting procedures..."

So, where too next? Well, I did mount them and saw the weight distributuion. As I have taken that tire off to use when I need a good tire for distance work, I will mount it 180 degrees off from where it was - to see if I can reduce the ammount of added weight.