Triumph Rat Motorcycle Forums banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Bike of the Month Challenge!

1 - 8 of 8 Posts

·
Registered
Joined
·
728 Posts
Discussion Starter · #1 ·
I managed to strip the valve core in the rear tire of my S3 this morning (tire kept losing air overnight) and now must replace the entire stem ( I have it on order)
Anyone here done this?, and any tips tricks I should know?
 

·
Premium Member
Joined
·
2,522 Posts
Replacing the valve stem is fairly straight forward. Usually, it is done with the rear tire off at least one side of the wheel, as I'm not sure you can compress the tire enough while still on the wheel to get to the valve stem. You just remove the old one, make sure the mounting surfaces are clean, and put the new one on. Tighten until you feel the gasket crush and begin to give some resistance to tightening (not too tight). Once the tire is compressed with air, pour some water mixed with a little soap over the valve stem to ensure there is no leakage.
 

·
Registered
Joined
·
440 Posts
This may sound stupid, but how often do you need to replace the valve stems?

Not every time you change your tires?
 

·
Premium Member
Joined
·
2,522 Posts
This may sound stupid, but how often do you need to replace the valve stems?

Not every time you change your tires?
It depends on what kind of valve stem is on the wheel. If they are fully rubber, it is good to change them when they begin to check. At least on S3, Daytona, S4, TT600, Sprint, etc., the valve stes are steel, so there is no need to replace them. I suppose the rubber seal between the valve stem and the wheel could eventually go bad, but that will take a very, very long time.
 

·
Registered
Joined
·
440 Posts
Thanks. I figured valve stems were a "replace once in a blue moon" item.
 

·
Registered
Joined
·
728 Posts
Discussion Starter · #6 ·
Update

The reason I'm replacing the stem is because I overtightened the valve core and broke off the "shoulder" on the core itself.
As for the S3,Sprint,Daytona all having steel stems your wrong.
They are aluminium and getting them out of the rim is a PITA.
It looks as if there is a straight slot for a screwdriver that keeps it from spinning as you loosen the 12mm nut at the base. However the stem is designed to strip as you remove the nut and the slot inside the rim is quite shallow.
I waited a week for the replacement
The replacement part was a standard rubber stem like Honda/Yamaha use however the hole in the rim is too small. Using the proper pull thru tools only made things worse. I had to go back to the dealer and ask for a stem off a 2005 or newer S3. which amazingly they had in stock. Although they insist it wont work because of the VIN# is wrong
2005 and up Triumph alloy rims have a 90 deg stem. 97 thru 04 have a straight stem.
The 90 degree is on right now and after removing the wheel cursing as I tried the 1st part (rubber) which will never work
and driving back and forth nearly 100 miles to and from the dealer
I am going to let the bike sit overnight and see what it looks like in the morning.
 

·
Premium Member
Joined
·
2,522 Posts
Stock 2003 Speed Triples have a straight steel valve stem on the rear wheel. This is not to say yours is oem. It is true that other models and years have aluminum valve stems (and at different angles), but when I said 'steel' I meant that 2003 S3’s (the motorcycle I thought we were discussing) are metal, but whether they are aluminum or steel makes no difference. The point is that metal valve stems don’t weather like rubber ones.

The valve stems are not designed to shear off or strip, so it sounds like it seized and stripped or broke off. I've taken off a few now and have never had that issue. If a dealership doesn't give you a straight steel valve stem, it's not the right one for that year, although it may work nonetheless.
 

·
Premium Member
Joined
·
2,522 Posts
Stock 2003 Speed Triples have a straight steel valve stem on the rear wheel. ... If a dealership doesn't give you a straight steel valve stem, it's not the right one for that year, although it may work nonetheless.
My saying 'steel' valve stem is a typo; I have no idea where my head was at that moment in time, as I was trying to relate that to my thinking of the stems as being metal. I meant that they should be straight aluminum valve stems for the stock rear of an 03 S3.:rolleyes:
 
1 - 8 of 8 Posts
Top