Inawise TPMS - ThreadID: 137665- Posted by Malcolm M

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When I was chasing Inawise the Chinese manufacturer (Baolong??) Asked how many thousands I wished to order!

Boobook I think your comments are a bit off the mark and unfair to the retailer . The markups you talk of are realistic and justified if you want to stay in business in Australia .
If you look at any of the big retailers those are the sort of numbers they run on.

And chase the inawise directors for what?

I'm going to do the same thing after losing a sensor down at Lucky Bay not long ago when bogged, dropped through the wheel into deep sand when I removed it for airing down a bit more. :(
No answer from the so called manufacturer somewhere in Asia, forgotten where, or the distributor here, and a local 4x4 store got a price of 106 bucks for a replacement.
Absolute rip off so a complete cheap replacement set is coming soon.
AlanTH.

I am now onto my 3rd set of batteries, glad I have externals, never seen any sigh of the sensor hitting the rims.

Peter

I am now considering a similar option after rethinking the value of the Inawise internal sensor replacement cost.

Any chance you can post the link to the eBay vendor of the unit you purchased.

Cheers John

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I started out with Tyredog internals. Had reliability issues so changed to Inawise internals. When the batteries neared replacement time Inawise had changed their design to a new frequency so a complete new system was required. The problem with that was the new unit had a fixed high-pressure alarm point marginally below the sometimes pressure of my rear tyres.
So I researched and found a simple, cheap, solar powered dash system with external sensors that did all I wanted.

Some of the perceived problems of external sensors was overcome by drilling the rims to fit extra valves to accomodate the sensors in a more protected location.

Initially I had chosen internal sensors to be able to observe realistic tyre temperatures which is something that externals cannot achieve. I have by now observed the relationship between tyre pressure and temperature for my vehicle so am satisfied to accept external sensors and not receive temperature data from within.

The big gains with the new external sensor system was lower system price, and possibility of battery replacement enhanced by my extra valve stems. I'm happy.

I highly recommend the Digioptions ones. Very good support, Gos down to 0 PSI for alarms, even a choice of internal or external sensors. Though you's be mad to get internal ones for off-road use IMHO>

The one I got is similar to this one on ebay https://www.ebay.com.au/itm/Universal-Solar-Power-Tire-Pressure-Monitoring-System-Car-TPMS-IP67-B8Z9/254235859214?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
You can buy them from local sellers for a bit more, if you need more than 4 sensors for a trailer then just install a second one for the trailer, they have a pretty good range.
Like other have done I drilled the rims for second stem and put a piece of that soft rubber insulation from Bunnings over the stem before screwing the sensor on which stops the stem wobbling a round and gives the stem and sensor a bit of protection. Having a dedicated stem for the sensor makes it really easy to deflate and inflate tyres with the main valve stem without having to remove the sensors.

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Mine receiver is similar but a bit smaller.
I also drilled for a second valve stem but used short metal rather than rubber. It is also possible to obtain short rubber stems that may solve the wobble problem.

Gentlemen

Some of you talk about drilling holes in the rims for an additional valve stem. I assume this assists with airing up/down.

I have considered this but have read on other forums that you cannot drill mag rims as it will effect their integrity. My Prado has mags and I am not interested in changing to steel.

Is there any real evidence that drilling mag rims will damage them irreparably. ie cause the rim to fail.

We air up/down a lot when we travel and it was one of the major reasons I paid the big dollars for the Inawise system. Ease of resetting the monitor for air pressure changes plus internal sensors for better internal temperature approximations.

I am interested in hearing your comments on drilling mag rims and airing up and down with external cap type sensors.

Cheers John

J&A&KK - There's no specific law that stops you from drilling extra valve holes in rims. But consider the following;

1. Drilling additional holes in premium alloy rims will reduce their value substantially if you ever wish to sell them.

2. Rims come under stress and flex from cornering and variations in loading, and hitting potholes, sunken culverts and other road undulations (or foreign objects).

When a hole is drilled through a metal item which is loaded to varying pressures, and which comes under stress and flexes, the potential is there for cracks to start anywhere there is a "stress riser" around the drill hole area.

Stress risers are sharp edges and deformations in the surface of the material.
Thus, if you drill additional holes in a rim, you need to ensure the holes are finished to a smooth finish, and that the edges of the hole are chamfered and smoothed off as well.

QLD's laws for "minor" vehicle modifications -

Vehicle Modifications allowable

Cheers, Ron.

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Hi John,

My rims are steel so the question of drilling mag didnot enter.
But, in considering drilling magnesium alloy wheels I would think that there should be no special problem. If it is acceptable to have the OEM hole in the rim I can see no reason to not have another similar sized hole diametrically opposite. To be sure, I have just asked my rather well skilled fitter/machinist mate who agrees with me that there would be no problem with wheel integrity.

Having said that I would express some provisos. In the case of steel wheels they are formed from sheet steel and the cross-sectional area (thickness) is essentially constant. I could not be sure that mag wheels are of constant cross-sectional thickness, in fact I would think they are not so. This being the case the outer and inner surfaces may not be parallel at the point of the hole which may affect the integrity of the seal of the stem to the wheel. I used metal rather than rubber stems but rubber stems may be more accomodating to wheel thickness variations. Although these metal stems are furnished with generous rubber sealing washers which would probable accomodate a fair amount of variation.

Certainly, I am happier with having independant mounting for the TPMS sensors. They are supplied with locknuts for security and I am free of the hassle of manipulating those each time of airing adjustment. The more important benefit is that I was able to position the sensor a little further in from the wheel's outer edge.

I'm not sure of the pros or cons of drilling wheels, but I have had external TPMS sensors since 2006, when they were expensive. I've never bothered with the locking devices and use the sensors as valve caps. My car has been parled in the street in an inner Melbourne suburb for that time. I've never had a problem.

IMHO it's just easy to use the caps without any locks. I've never lost once by it coming loose either.

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Hi Ron,

Responding to your point 1), you may well be right, but I care nought for the "value" of my car for resale. In fact I intend to take it with me to the Great Desert in the Sky when I go. Lol
As to point 2) , well any holes I place in my vehicle are finished to remarkable quality. In fact the best of them has been mounted and framed and is hanging proudly on the dining room wall. Lol. If I had a dollar for everyhole I have drilled in myTroopy then you and I could have lunch together on the proceeds.

And of course, if putting holes in things weakens them, then there are a lot of airframes at risk!

Hi Allan - There's no basic problems with installing holes, it's often done to promote lightness without compromising strength too much.

But the the location, the shape, the finish, and the surface condition of the hole, in a highly stressed member, is what can initiate and promote cracking, if not carefully designed and finished.

In aircraft, holes in frame members are smoothed and deburred - and all frame members with holes in them are regularly maintenance checked, to ensure no cracking is propagating from the holes.

Lightening holes

Cheers, Ron.

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It was a joke Ron.

Gentlemen

Many thanks for the variety of feedback. Much appreciated.

I will probably go with a cheap unit with external caps on the existing valve stems and just remove them when airing up and down. If that solution proves to be unacceptable to me I won’t have spent a lot of money. Not like the Inawise unit purchase decision. Mind you the Inawise has saved me 3x tyres in the past 5 years so has probably paid for itself.

Cheers John

For what it is worth it is possible to replace the batteries in the internal strap on sensors, very time consuming and you may possibly damage a sensor while attempting to remove the potch that they seal them up with. I managed to dig the potch out of four of them but only three started working again with new batteries which are available online for about $2 each.
The sensors are a poor design as they could have been designed and made to enable battery replacement but of course that stops the retailer from having an ongoing income selling new sensors at $80 a pop every few years.

Hi Peter

Thanks for the suggestion. It’s worth a try. The sensors on my system are attached to the valve stem not strapped to the rim.

I will have a go at a dead sensor that’s in the van spare and see what happens. That by the way is another issue with internal sensors. If you rotate your tyres regularly, and include the spare (truck and caravan), you need sensors in every wheel. In my case 8 sensors.

However it’s worth a try. I have found that a Dremel, mounted in the vertical drill press, is very good at reaming out resin type material. Just need to be fussy when setting up to get the fine control needed. If it works I just need to think about how I will get around, have 5 new tyres fitted and ream out the sensors.

A good challenge at this time of life. I definitely have the time.

Regards John