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Iron horse

Tyre Pressure Monitoring System

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Iron horse

There's an auction site I know of selling these for £35. Rechargeable battery powered, so no wiring fuss. Has anyone tried one? 

 

The instructions don't make much sense but the interface looks  pretty clear

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JamesS

Are you allowed to post a link, so we can have a look?

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Andy m

 I have a horse in this race, so you will understand some bias. I sell TMPS for trucks. 

 

These sensors are generic and now heading towards obsolescence, external sensors have been replaced by internal and they will be in the tyre wall in a few years. There is a good reason for this, the rim is not a nice place for electronics, they fail quickly. These have a temperature display, so unlike the real garbage are not someone's college project. You need the temperature so you know what is decreased pressure due cooling after a ride and what is an actual leak. 

 

What I would say these are are semi approved-knock offs. The Chinese are contracted by known manufacturers to make the parts and off their own bat or by agreement sell the same thing unbranded into undeveloped markets. Bike retrofit is not worth the work so is such a market. 

 

What you do not know is if these are what VW or PSA allow them to sell with their own receiver or what the Chinese fished out of the reject bin. The supplier does not show the IP rating or any of the relevant RF specs so is clueless. This simply means you may find they fail in the first rain storm, may switch the whole streets tellies to Channel 5 or may work for years. For £35 you won't starve, so this is not a huge concern. 

 

Why I would not buy these is a simple mechanical problem. Your nice EC approved valve stem is not designed to support a sensor. If it fails by vibration and the neck goes you won't need TPMS to tell you, the blowout will be obvious. Ones like item 254003000697 meet this design issue by giving you a new valve with a metal neck. Your air is then held in by unknown Chinese valves bought cheap off the auction site. 

 

IMHO, Buy a decent digital gauge and wait until you can spec TPMS on your next bike. Car legislation now and trucks before 2023 means tyre checks will be so far from standard the bike market will have to follow. American lawyers drive a lot of standardisation. As I doubt there will be legislation on bikes they may even go the indirect route using the ABS sensors which means no extra weight and nothing to go wrong. 

 

Andy

Edited by Andy m
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rjp996

Always wondered about these, as I assume that the cap holds the valve pin in, meaning the primary mechanical mechanism for holding air in the tyres becomes the cap instead of the valve, and hence I've steered away from them. 

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Andy m

The pin is indeed held open. Good external sensors connect a pipe with another valve and a T. The sensor is on the T so just part of the tyre volume and still sealed by an EC approved valve with a flat O ring in compression. 

 

Using a plastic thread to hold it open is not great. What should happen if it goes is that the schreader valve will close. If there is a leak path round part of the sensor though you have a slow puncture. Having the alarm go off to tell you is fine, but not as good as not having the leak in the first place. 

 

I haven't adjusted the pressure on the CB for 4000 miles. Trucks are different as the pressures, loads and mileages are higher. If you have a blowout on a petrol tanker and the safety elves close the M25 to tidy up the mess the bill can be huge. 

 

Andy

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arengle

for £10 more you will find on that site, internal tpms, if you really need one, go for internal one, it's much safer. you can install it then you will do next tyre change.

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pjm

I have had the Garmin ones in a variety of bikes with no issues. I had one that leaked a bit and the6 replaced it FOC. Personally I can’t  wait until they are standard as I have had them save me from getting stuck on two different cars so far.

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Mr Toad

There are internal sensors on the GS, very handy but my first question was what happens when the battery goes flat? Is it as simple as removing the tyres and replacing the batteries, or waiting until the next tyre change?

 

No, you can't replace the batteries, you replace the sensor and they cost anywhere from £39 off fleabay to £106 each from BMW. I have no idea how long they last but I won't be replacing them once the batteries go. I have a decent digital gauge and I'm not afraid to use it.

 

That said there are hacks on YouTube showing battery replacement.

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Dave H

I have a tyre pressure monitoring system on my SEAT Alhambra. I don’t know the technical details but it works by utilising the ABS system   It seems to work okay as if it warns me there’s a problem then the pressures have dropped about 10%. 

Most bikes have ABS so it should work there as well. 

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Matatpub

I have fitted the tpms on my Africa twin and it works great and tells you how warm the tyres get 

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Iron horse
2 minutes ago, Matatpub said:

I have fitted the tpms on my Africa twin and it works great and tells you how warm the tyres get 

Which one was it?

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Matatpub

Onewell  motorcycle tpms 

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