Slow puncture

[Jings]

I've got a slow puncture in the rear (Pirelli Angel GT with about 6,000 miles on it).

The bike is used daily, 50 mile each way commute. In the morning the red warning light is on and the TPMS indicates about 36-38psi. I top it up to 42-44 which will be fine for a few days before the pressure gradually drops again.

The tyre still has a lot of tread left and if it wasn't for the leak I'd probably hope for another 2,000-3,000 miles out of it, but I am concerned that a small hole could suddenly become a bigger hole especially at speed.

To top it all, my work circumstances might be changing in a couple of weeks, meaning I no longer need to ride to work - in fact I will no longer need the TTSE at all... so I am keen to hold out for a couple of weeks if I can before replacing the tyre if and when I sell the bike.

Would you be tempted to ride another 1,000 miles in 2 weeks with a known slow puncture that seems to be manageable?

[GarminDave]

A true dilemma.

It focuses the mind when at high speed, in the wet on a bend will you think I wish I'd spent £150 on a new tyre!

I'd buy a new tyre, the actual or perceived issue is not worth the worry.

Just my $0.02 worth.

Love, light and kindness,

Dave

[john348]

But isn't it great to get a display on the dash to see what is going on.  I seem to have a similar problem with the front but difficult to put a finger on.  It seems to stay the right pressure for ages and then suddenly looses a couple of pounds but slowly.  I pump it back up and all is fine again for ages?  This is an rp4 though?  To start with I thought it was just when the temperature was getting cold showing a lower start pressure but I am sure now it is loosing pressure rarely.

Perhaps some trips I ride too fast and the tyre spins out and looses air??????

[Volfy]

If the puncture is near the center of the tire and preferably on the "land" instead of groove, you should be fine... if you did the repair well.  "Derate" the speed rating on that tire down to, say, 85mph in your mind and watch that tire pressure like a hawk.  I did that with a Angel GT rear tire on a Speed Triple R.  I was only a few months away from selling it, and wanted it shown with brand spanking new tires at time of sale.  It was a PITN to check tire pressure manually before every ride, but I managed it.  The TPMS readout should make it easy on the TTSE.

If it's near the sidewall, where the tire will flex, then I wouldn't risk it.  Any plug there is only very temporary till you can get it swapped out ASAP.

[Jings]

Sorry Volfy, I should have been clearer... I haven't repaired anything. I can't see any puncture and I am just assuming that there is a tiny leak somewhere, such that the TPMS drops from 42 to 36 over a few days.

If there was any visible cause of a puncture I would replace immediately, but with a seemingly minor leak like this I am a bit more hesitant to replace while the tyre still has plenty tread left.

I am riding with one eye constantly on the TPMS at the moment!

[earthman]

Originally Posted by Jings

Sorry Volfy, I should have been clearer... I haven't repaired anything. I can't see any puncture and I am just assuming that there is a tiny leak somewhere, such that the TPMS drops from 42 to 36 over a few days.

If there was any visible cause of a puncture I would replace immediately, but with a seemingly minor leak like this I am a bit more hesitant to replace while the tyre still has plenty tread left.

I am riding with one eye constantly on the TPMS at the moment!

First off, are you sure that the tyre is actually loosing air? Checking with another air gauge for example.

If it is and there's no sign of a tiny nail etc that's the cause of a puncture then maybe the inner core of the valve is leaking, try unscrewing it and fitting another one. Apart from that, maybe the tyre isn't sealing itself against the rim correctly or that the wheel casting has become porous. Hopefully it's not the the last one,....I did hear that that were happening a bit to often on the Yamaha R1 during a period of time, turns out that they were making them just a bit too thin, to keep the weight down I guess.   

[janfmiller]

IMHO, the TPMS is only a 'warning' and should not be used to verify tire pressure, I keep it displayed always, and watch it like a hawk, great tool, has alerted me to a slow puncture twice.  But I use a quality guage, or a pencil guage I've verified against a quality guage, a couple times a week, just like I did my whole riding life.

I have a compact Stop&Go 'mushroom-plug' type system, but have had mixed results with that ( if you do have one be sure and pull the stem hard to seat the 'head' inside the tire ).

That said, I'd find the leak and patch it with a rope-type gooey patch kit, if you are not planning a high-speed heavy load trip on the tire, or fast technical riding; I routinely do this. 

I HAVE patched a tire and ran it to the end of it's life on a road trip, but I worry the whole time about it failing. 

It's hard to discard a $250+ tire with 2-3000 miles left on it, but .. that's probably the RIGHT thing to do..  And definitely the right thing to do before a trip.

[john348]

To be clear I have a couple of proper gauges that I use whenever I out air in the tyres or approx once a week to check.  I then use the display for confirmation and looking for warnings.   I have one of the gauges under the seat for when I am out.