Doran Tire Pressure Monitor Concerns

[BMUU]

I’m curious if anyone has installed the Doran 360M tire pressure monitor on an 1100 – 1150RT and what your experience has been. I just purchased this system and although I really like the concept, I’m now having second thoughts about my decision. In particular, I have some concern that the metal valve stem won’t fit securely due to the circumferential ridge running along the inside of the wheel and its close proximity to the valve stem hole. It also appears that the original stem is recessed into the wheel. My concern is compounded by the fact that two BMW shops, both of whom I trust, have refused to install the stems due to safety concerns. I spoke to a third shop and they too refused to install any system that required replacing the original stems.

 

I’ve actually thought about fabricating a mount utilizing the Doran sensors and a large band clamp, but unless it was actually produced by Doran, I think I’d have the same difficulty getting it installed. Besides having a genuine concern for customer safety, I’m sure the shops are also understandably concerned about liability issues.

 

Are there any other TPMS available that don’t require replacing the original rubber stems? One unit that gets high praise is the Smart Tire, but it appears to have been discontinued. Are there any similar units out there?

 

Thanks!

[smiller]

While I don't have any experience with the Doran system I can say that there are several types of metal valve stems that work fine with the 1100/1150 wheels so I wouldn't be worried on that point alone. Do you have a general concern or have you confirmed a specific fit issue with the Doran sensors?

[BMUU]

I haven’t confirmed any specific fit issues with the Doran valve stems. I’m largely basing my concerns on the responses I’ve received from the three BMW dealers I’ve talked to, all of whom I’ve come to trust. They have three basic concerns. First, the proximity of the raised circumferential ridge on the inside of the wheel would prevent the nut securing the Doran stem from sitting flush. Their second concern is the fact that the original rubber stem is recessed into the wheel and the diameter of the recess is almost as large as the securing nut and washer for the metal stem. This might make it difficult to securely fasten the new stem. Lastly, the new stem is longer than the original BMW stem, potentially making it difficult to inflate the front tire, due to interference from the disk brake rotors.

 

I don’t have the tools, or the experience to install the stems myself and this isn’t something I want to experiment with! I’m really at the mercy of the dealers. If they refuse to install them, I’m kind of out of luck!

 

[DavidEBSmith]

Actually, the Doran system doesn't "require" replacing the rubber stems, it is "highly recommended", and it looks like you would only need to install their valve stems if you want to mount the sensors inside the tire instead of outside.

 

From the pictures in the users manual, I would predict that if the sensors are mounted inside the tire, at least one will get broken by the Neanderthal tire-changer at the local shop.

 

The current set of tires on the bike, I thought about replacing the rubber stems with metal ones to better support my Show Chrome tire monitors (which are pretty similar to the Doran ones), but then I thought, "meh", I have a whole bag of rubber valve stems and I can just replace them every time I change tires, and the TPMs are not likely to rip the rubber valve stems off in 12K miles.

[Ken H.]

Recognizing that the R1100/1150 wheels are a bit different that the R1200 wheels, the R1200’s still have the ridge. I put the Doran on my R1200GS using their provided 90° stems. (So the sensor could be on the inside.)

 

I too had a concern that the washer and nut (on the outside) couldn’t go fully flush because of the ridge. So I ground a flat spot on opposite sides of the washer so it would drop between the ridge on each side of the stem hole to be (near) flush. Then I cranked the nut down enough that it distorted the washer a bit more to conform to the outside contour of the rim. Not sure if the same approach would work on the R1100/1150 wheel, or would the nut itself also still contact the ridges and not be able to tighten down on to a modified washer?

 

The air seal is really made on the inside of the rim anyway, and the rubber there that comes with the Doran stems is easily big enough to span the hole and form a seal, so the only real potential for an issue is if the nut started to back off and cause the stem to loosen in the hole. If that is a real concern to someone a bit of thread locker (Locktite type product) would add even more peace of mind.

 

I haven’t ridden the bike a real lot sense I installed it, only about 600 km, but so far, no issues.

 

Dealers’ concerns are the legal department taking more than anything in my mind.

 

And besides, you now have a tire pressure monitor! If the stem should start to leak, well, you’d get an alert! That’s what the systems there for, right?

 

 

[smiller]

Not certain but it appears that the Doran sensors will work with any metal valve stems, and if so you can just buy some 3/4" metal stems from Patchboy and you should be good to go as these fit without modification (definitely on the 1100 three-spoke wheels and probably on the 1150 wheels, hopefully someone can confirm the latter.) If so then this should be a very easy job, and if you need someone else to install them I don't see why there would be any objection since no mods are required to the stem or wheels.

 

As a side comment I'll note how happy I am with BMW's TPM system. It's the first TPM system I've ever used and I have to say that I find it much more useful than I would have thought. Most of the other BMW trip computer stuff is kind of silly (in that it's almost as functional as a simple trip meter ) but the TPM system is of real value and I'll definitely install/order one on all future bikes.

 

 

Edit: I just called Doran and checked and if you are mounting the sensors externally you can use any metal stems. The included stems are required only if you will be mounting the sensors internally.

 

[Ken H.]

Edit: I just called Doran and checked and if you are mounting the sensors externally you can use any metal stems. The included stems are required only if you will be mounting the sensors internally.

Yes, the Doran stems are threaded internal as well as external.

 

One (bit of a) negative, by the time I added the rather large 90° stems and the sender, it required a lot of opposite weight to balance the wheel, but that’s the price you pay to get the system.

[BMUU]

I actually thought about installing the sensors on the outside of the wheel, but for a variety of reasons, would prefer they be on the inside. I think that rules out the 3/4" "Enkei" style stem from Patchboy. I also can’t use the 90-degree stem supplied by Doran, as it comes dangerously close to the brake calipers in the front. Interestingly, the 90-degree stem is larger in diameter than the straight stem (0.41” vs 0.33”) and would probably provide more than adequate support. Not sure why Doran doesn’t supply a larger diameter straight stem, similar to the one from Patchboy.

 

As far as mounting the Doran stem on the existing rubber stem, Doran issued a technical bulletin in July 2009, advising that the sensors should only be installed on tubeless tires with metal stems. To quote their bulletin, “. . . system is NOT designed to be installed on motorcycles or trikes with rubber valve stems and / or tires with tubes.” They point out that the sensors have enough mass to cause rubber valve stems to fail, which may cause a, “sudden loss of tire pressure and blowouts.” It may be that other external sensors (Show Chrome) are be smaller / lighter than the Doran units, which are rather large and bulky.

 

I would really like another option, similar to the now discontinued Smart Tire, that does not involve the valve stem, but I am not sure that exists. It would sure make it a lot easier to get the system installed!

 

Thank you all for the help!

 

[BMUU]

A quick addendum to my previous post.

 

I just spoke to Doran to confirm that this system has been successfully installed on an 1100RT. As I suspected, they have many satisfied customers with 1100 / 1150RT’s. Unfortunately, as helpful as they were, they were not able to provide me with the names of any shops in the Chicago area that would be qualified / willing to install the sensors.

 

I’d really appreciate it if anyone on this forum knows of and would be willing to share the name of such a shop. As big as Chicago is, I have to believe that somewhere out there is a mechanic who’s done this exact installation before.

 

[DavidEBSmith]

The Show Chrome sensor is listed at .34 oz, although I weighed mine at .45 oz with the battery. The Doran sensor is listed at .67 oz. Show Chrome specifically says that the original valve stems can be used, although maybe Gold Wings come with metal stems, I don't know. The display is battery powered and so would be somewhat less convenient than the Doran one that's hardwired.

 

I don't know who you've tried in the Chicago area who has refused to install this, but I'd suggest calling MotoWorks at 1901 S. Western. In the past they've had no issues with installing customer-supplied parts, tires, etc.

[BMUU]

Thanks David, I'll give them a call tomorrow.

[Ken H.]

I also can’t use the 90-degree stem supplied by Doran, as it comes dangerously close to the brake calipers in the front.

Don't install them perpendicular to the rim, install them on a 45 or similar?

[KevinH]

I have some concern that the metal valve stem won’t fit securely due to the circumferential ridge running along the inside of the wheel and its close proximity to the valve stem hole.

 

You can file open that ridge for Metal Valve Stems. Not pretty taking a file to a rim but hardly noticeable.