New new guy stuff

[timburn]

Rode 50 miles yesterday and had a blast. This is more agile than the R75/6 ever was. Today, jumped on got 1/4 mile. Felt odd found rear tire VERY low. Limped home. Tried to put air in, came right out around the valve. I have never had cast wheels with tubeless tires before. When I did cars, you pulled a valve stem through rim and a groove locked in. Only Haines manual has shown up yet, and it was a bit lacking in details. Where am I?. Pull rear wheel ,bust tire and replace stem?
Help.
Tim

[Luca]

The LS and standard R65 as well are supposed to run tubes.  The bead on the rim is called a WM-2 style and it does not hold the bead as well as tubeless wheels.  Many people have successfully used tubeless tires on our cast wheels, but I think you might need to open up the valve stem hole to do so.

As long as the sidewall isn't split don't "bust" the tire, if that means trash it.  Put a tube in.  I put Metzeler natural rubber tubes in mine under Spitfire tires.  Nice thing about the Metzelers is that you can get one tube fits both wheels.  If you have the coin, grab yourself a spare incase you pinch it during installation.  If you don't wreck a tube, put the spare under the seat or in your toolbox for the next tire change.

Count yourself lucky that it wasn't you front tire that went flat!  And one last thing:  many "tubeless" tires will run just fine with tubes in them.  The problem is usually the other way around.  A rule of thumb is to knock a letter off your speed rating when putting a tube in a tubeless.

[montmil]

Tim,

I run Bridgestone S11 Spitfires on my '81 R65... tubeless. No issues for several years now.

Of course, it's necessary to fit tubeless valve stems. I use the short, angled stems that provide easier access for the air chuck. I also notice far less tire pressure drop over a week's time with the tubeless tires than occurs with the '83 R65 tubed tires. Anomaly? I dunno...  

As an aside, please add your model year R65 to your sig line/location info. Differences between mfg year and models, ie: Std R65 v R65LS may require different answers. Please help us help you.

[timburn]

More ?
Would it be ok to tighten down knurled nut on Valve stem to see if just loose? How much? I am not a sutle guy and putting vicegrips on something I can't picture scares me. Many broken off bolts/studs in my past. But if I will have to replace anyway???
Tim

[Bob_Roller]

Try tightening it up a bit more, use some window cleaner as a leak check, if you tighten it up and it still leaks, you're going to need to repl;ace it .

There's a rubber washer on the inside, this is what does the sealing, the valve stem does not lock into the wheel .

[Luca]

I also notice far less tire pressure drop over a week's time with the tubeless tires than occurs with the '83 R65 tubed tires. Anomaly? I dunno...  

Natural rubber tubes leak air at a pretty good rate.  It comes out right through the rubber and makes its way along the rim and out of the valve stem hole, which isn't sealed in a tubed tire setup.  If you have a tube-only tire, sometimes those will leak air right through as well.  Tubeless tires are sealed on the inside.

FWIW, butyl rubber tubes hold air much better than natural rubber, but some say they are more prone to rapid deflation (blowout style) and tearing.   yeah, yeah, I know... friend of a guy who said his mother told him...

[k_enn]

More ?
Would it be ok to tighten down knurled nut on Valve stem to see if just loose? How much? I am not a sutle guy and putting vicegrips on something I can't picture scares me. Many broken off bolts/studs in my past. But if I will have to replace anyway???
Tim

If that is the nut I am thinking about, that is tightened down to the rim only when installing the tube.  Once the tube is in and inflated, the nut is supposed to be raised up from the rim.  The purpose for raising it is to allow some room for the tube and its valve stem to flex and shift a little when needed.  If it stays tightened down, you increase the likelihood of ripping the tube where it joins the valve stem.  

Are you sure that you are running tubeless?  It is very common to use tubeless tires with tubes on these bikes.  

[timburn]

Not at all sure there is not a tube . Sure looks like thw tube stems I am used to. I think I just need to pull the wheel and look.

[Rob Valdez 79 R65]

If this bike is new to you, you need to determine the age of the tires if you don't already know the history.  You would probably do well to plan to spend some money on fresh tires and tubes.

As said above - get natural rubber for maximum safety, get butyl for convenience.  

And don't tighten down that outside nut!  Exactly as k_enn said above...
If you suspect something of being loose, it would be the valve inside of the stem.  It can be removed for cleaning and inspection, or replacement.  All you need is a valve stem cap with a do-hicky on it for removing cores.  See your auto parts store.

[Luca]

It is easy to determine if you are running tubes.

Deflate the tire, leave the lock nut on the valve stem near the top.  If the entire valve assembly want's to push into the rim, you have a tube.  If the valve is fairly rigid, no matter the tire's pressure, you have a tubeless tire with a separate valve assembly.

You can perform a leak down test of sorts to make sure the the tire is holding air.  Fill it to about 50psi at night and check the pressure in the morning. Given that you went from a great 50 mile ride to a squishy quarter mile, I'm willing to bet your tube/tire is compromised in some way.  A visual inspection might help.  Look for punctures, deep cracks, etc.  If the tube is leaking, you could check for that by putting soapy water, window cleaner, or something else that bubbles around the valve stem hole in the rim, the valve itself, or the tire bead.

As said above, if the bike is new to you, you should really assess the condition of the tires.  Keep in mind that old tires with good tread will crack along the sidewall pretty quickly.  When I go my bike last year I rode it on the decent looking factory tires for about 1K miles.  They aged very quickly!  Fortunately the tubes looked great when I put in new tires and tubes.  It was still a pretty stupid decision to ride them at all though...

[Bob_W]

Mono socks were factory equipped with tubeless.  A leak in the tube will push air out the valve hole with a tube. I know I just finished replacing a lawn mower tube. Lots of air blew out around the valve stem.

[k_enn]

Mono socks were factory equipped with tubeless.  A leak in the tube will push air out the valve hole with a tube. I know I just finished replacing a lawn mower tube. Lots of air blew out around the valve stem.

IIRCC, 1983 was dual shock came from the factory with the snowflake rims that are supposed to be used with tubes.  That's not to say the PO did go totally tubeless.

k_enn

P.S.,  
Luca, nice point on testing if there is a tube or not without breaking the bead.