Aircap tyre pressure monitoring system

[dtm0211]

Hi All,

Has anyone here had experience with the fairly cheap (50 pounds) aircap mounted type pressure monitoring systems? Do they work or fail after a short time?

I would happily go to the internal pressure sensor type but the only downside is when i change a wheel during a trackday i cannot change the pressure sensor with it.

Any advice please.
Many thanks

[dtm0211]

another model is a more expensive route known as the tyrepal - approx 200 pounds - is it worth going to this level?

[andrewc]

ran tyrepal system on a single seater formula car several seasons agoas intended running pressure when hot was about 4-6psi hotter than ambient.

Worked OK, but the system we used updated every couple of minutes, which is fine for road car usage but less satisfactory for track use, so if buying again would look at options with either real-time option or something with a short update frequency, and accept that the battery life in the sensors would suffer. No problems at scruitineering either.

Thankfully never had a puncture but sudden pressure loss should have triggered an alarm, you notice alarm in a normal car, but unsure whether driver would notice in a single seater (noise / vibration / generally being busy) is another matter. More likely would feel it first and could then check display for flashing light.

[dtm0211]

great thanks for the interesting points. i thought they were all real time sensors - its good to know that some are interval time updates. thanks.

i also thought that the aircap models are relying on the cap tightness in order to keep the air in. It is intentionally pressing in the tyre valve yes?

[Gerard C]

Yes it is at least on the ones I used for a while but not race tested.
Tanks for you very interesting question, an affordable and reliable system on the valve itself could be useful.

[andrewc]

Certainly the ones a couple of years ago were polled at intervals, they press against the tyre valve pin in order to measure the sensor (you can hear a momentary hiss as you fit them or release them)

[Johno.UK]

Thing to be careful of with the cap type systems is that they are easy to damage with wheel to wheel contact which, with they way they work, can mean losing a lot of pressure very quickly. I use them for practise sessions to get an idea of what's going on pressure wise without constant trips back to the pits but I wouldn't use them for a race situation.

[andrewc]

Depends on the wheel I suppose. On the single seaters they were pretty recessed, and if they were going to get damaged in an accident, you were already involved in a pretty serious accident.

[peebee2]

Originally Posted by Johno.UK

Thing to be careful of with the cap type systems is that they are easy to damage with wheel to wheel contact which, with they way they work, can mean losing a lot of pressure very quickly. I use them for practise sessions to get an idea of what's going on pressure wise without constant trips back to the pits but I wouldn't use them for a race situation.

Do any series allow them for racing now then?

[andrewc]

Had no issues racing with one in a UK single seater series. Passed pre-race and post race scruitineering with no comment, and not in any regulations.

[Adam43]

I’ve played with them. They aren’t that expensive so I thought why not.

I tried to see how the pressure changes as the tyres warm on each corner. It helps if you can’t check pressures straight after being on track.

Not a game changer, but kind of interesting to do.

[Johno.UK]

Originally Posted by andrewc

Depends on the wheel I suppose. On the single seaters they were pretty recessed, and if they were going to get damaged in an accident, you were already involved in a pretty serious accident.

Single seaters maybe but certainly not in a tin top. Wheel to wheel contact is extremely common with no issues usually but the cap type sensors protrude quite a way out on most tin top type wheels.

[Trikes]

I use an Orange (brand) system in my Integra. It's given me the advantage of being able to watch my tyre temps come up so in short races I know when I have best grip. It also monitors in psi or Bar etc. It's has alarms for low and high pressure. But I luv the fact I know when too go step it up or just wait another turn or two.... I purchased a couple of extra Sensors for my spare wheels.

[Paul D]

I bought a cheapo set off eBay for about 20 quid - at that price, I thought it was worth a punt.

As others have said - I wouldn't have them on during a race, due to the possibility of damage and/or sudden deflation. They do stick out slightly on my wheels, so would be vulnerable in close racing - a scenario much less likely to occur in qualy. So, I tried them in qualy, on the basis that, as long as I'd got a few laps in before they caused any potential problem, then at least they couldn't ruin my day altogether, as they most certainly could if one failed in a race.

Really, I was just looking for some idea of real-time pressures. The ones I got weren't that accurate, but that doesn't matter as long as you know how much they're out by at a given pressure, which is easy enough to establish.

My experience with them was that they did update throughout the session, but one of them shut down for some reason and failed to provide a reading. The other three increased as expected, and ended up showing the sort of numbers I would have expected (when corrected for error). So partially useful, and it's interesting to see how quick the tyres get to a given pressure, and also to be able to see the differences based on all tyres starting from the same pressure. So, yes, a useful exercise for 20 quid. Haven't had a chance to try them again since, or to see if I can coax all four to provide readings. but I guess you can't expect too much at the price, from something that was really designed for the relatively peaceful environment of a road car, not the harsh environment of racing.