FOAK : Tyre valves

I have a leaky valve stem that losing 5psi a day - its leaking around
where the valve enters the wheel.
Is there a bodge to seal it up or will I have to get this tyre off the
damn wheel?

Steve

 

Slime

 

I'd go with that - and asap, too: if the thing is leaking then it's
either damaged or perished and losing the valve to sudden failure, at
speed, could be a little uncomfortable.

 

Yes, but: you're a racer, a demonstrably competent road rider - and a
really lucky ****. I'd say that in comparison a mere mortal might find
things like this more difficult to cope with, and that's why I used the
phrase "a little uncomfortable" rather than a more emotive YER GONNA
CRASH AND DIE!!!!

If you see what I mean. Like.

 

"A little uncomfortable" might still be overstretching it. Although I
suppose in conjuncion with "might" I'd allow it.

Only time it happened to me was on a French autoroute returning from
watching the ecclipse in 1999, and I almost didn't notice it at all.
Stopped for petrol, then rejoined motorway and accelerated up to a ton
or so, only thinking after a few minutes that it felt just a little
bit squidgy, and continuing to ride for perhaps another five minutes
before deciding I ought to check what the problem was. I was utterly
gobsmacked to find that the rear tyre was absolutely completely flat.

 

Only blowout I've had was in the Porsche, doing 140ish on the Swindon
ring road. Span it right round (thankfully without hitting anything) &
left me a tad more than slightly breathless.

 

My SOB CBX550 had a similar problem, with no obvious damage to the tyre or
the rim.

In a (rare) flash of inspiration, or should that be desperation, I tried the
following...
- With the bike on the stand and an axle-stand under the engine, taking the
weight off the front wheel.
- Removed the valve core and totally deflated the tyre.
- Sprayed Holts Rubber Lubricant around the valve housing and the valve hole
in the rim, working the housing by hand until it would turn with little
effort.
- Replaced the valve core and reinflated the tyre.

This resulted in no subsequent loss of air for the next five years I had the
bike.

YMMV but it's worth a try and can't do any harm.

 

Tubed tyres can let go pretty quick too. The rear on the Morini 375
rapidly deflated on Pahnd Island a quarter of a century ago. I was
coming down in to Foxdale off the Round Table road. Used all my side of
the road and a bit of the other on a fastish left hander before bringing
it to a halt.

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+-------------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+

 

Strangely, the faster you go, the less these kind of things bother you.
I was riding Ratty's ZX6R round Mallory the other week and got quite
used to the arse end spinning up on the power out of every corner
because the tyre was fucked. If that sort of thing happens on the road
at half the speed, I crap myself, but I just carried on going at the
same pace and got used to it.

 

Deflate tyre, slacken valve stem nut, push down stem, finger in some
silicone sealant, tighten back up. It'll work for a while, but not a
substitute for a proper removal and cleanup/replacement.