CHIGEE AIO-5 Lite - Apple / Android CarPlay

[wspollack]

Bill,

Here’s the CAD drawings for the BMW stem from Chigee

What's a little disappointing, a little puzzling, etc., is that the distance between my two green arrows is not listed (or calculatable).



This, IMO, is the most critical measurement of all. I will certainly measure that when the assembly arrives, and report back.

 

[mgg]

This is a feature that would be nice to have. I admire your tenacity and your willingness to figure this out and freely share the information. Thanks!
I check and adjust the air in my tires at the begginging of the riding season. Check and adjust again about midway into the season and that has worked so far. I should probably check them more often and would if I had sensors but don't because it is a PITA.
I put sensors in my challenger when I had the tires changed. I purchased the base unit which did not come with sensors. But everything was set up and all I had to do was initialize them after the install. Still the price of the sensors were $129.00 per wheel so $260.00. I purchased a whole set of sensors for my Mini Cooper for $89.00 and put them in myself on my snow tires. This one also looks like it is going to be kinda expensive.

 

[wspollack]

@byee, @mgg, et al.:

I received the Chigee stem today, and just finished taking some measurements.

The products (keeping in mind that I bought the BMW version a couple of years ago, so I could examine it):





I couldn't get a direct measurement of how much each stem would stick out from the outer surface of the spoke, i.e., that distance between the green arrows in my post #41, above. That's because if I placed one caliper jaw behind (i.e., at the bottom of) the nut, I would not be able to get a "level" reading of the valve-cap end of the stem: because the diameter of the inside-the-spoke threads is greater than the diameter of the outside-the-spoke threads, the stem would be tilted in the area between the caliper jaws.

However, I realized that I could get accurate measurements by firmly screwing down a spare FOBO sensor on each stem. Because the TPMS sensor is wider than the part of the stem that goes inside the spoke, I could get my measuring caliper squarely around the stem-with-sensor, with no tilting of the stem-with-sensor in between the jaws of the calipers.

Here's my photo of positioning the Chigee for measurement:



And here's the positioning of the BMW stem-with-sensor:



And here's the actual Chigee measurement:



That total distance is about 0.9604" (i.e., that last digit is an estimate).

And here's the BMW measurement:



That measurement is about 0.9935" (i.e., that last digit is an estimate).

Those measurements would change slightly, of course, using TPMS sensors of different brands. But my point here is that they provide a measurement of the difference:

Check my work, please, someone -- caliper readings and math -- as this seems to be my result:

Using the Chigee stem instead of the stock BMW stem results in 0.9935" - 0.9604" = 0.0331" (0.84mm) of less sticking-out-toward-the-brake-caliper of whatever you put on the end of that stem. That's not much: about three-hundreths of an inch (or less than a millimeter).

I know that a FOBO sensor will smack into a front brake caliper, because I checked it out a couple years ago (and bought a rolling-pin-like stand to be able to rotate the front wheel easily). I don't have a great way of measuring how much the sensor would contact the caliper -- I don't have any other kind of measuring calipers -- but I don't think three-hundreths of an inch is going to make things all right.

If someone has the Chigee sensors and is willing to buy the Chigee stem like I did -- the one supposedly compatible with the jackass placement of Schrader valves on the C 400 GT -- I'd be interested in knowing if the Chigee sensors protrude much less (if at all) than the FOBO gen. 2 sensors.

 

[byee]

@byee, @mgg, et al.:

I received the Chigee stem today, and just finished taking some measurements.

The products (keeping in mind that I bought the BMW version a couple of years ago, so I could examine it):

View attachment 5214

View attachment 5215

I couldn't get a direct measurement of how much each stem would stick out from the outer surface of the spoke, i.e., that distance between the green arrows in my post #41, above. That's because if I placed one caliper jaw behind (i.e., at the bottom of) the nut, I would not be able to get a "level" reading of the valve-cap end of the stem: because the diameter of the inside-the-spoke threads is greater than the diameter of the outside-the-spoke threads, the stem would be tilted in the area between the caliper jaws.

However, I realized that I could get accurate measurements by firmly screwing down a spare FOBO sensor on each stem. Because the TPMS sensor is wider than the part of the stem that goes inside the spoke, I could get my measuring caliper squarely around the stem-with-sensor, with no tilting of the stem-with-sensor in between the jaws of the calipers.

Here's my photo of positioning the Chigee for measurement:

View attachment 5218

And here's the positioning of the BMW stem-with-sensor:

View attachment 5219

And here's the actual Chigee measurement:

View attachment 5220

That total distance is about 0.9604" (i.e., that last digit is an estimate).

And here's the BMW measurement:

View attachment 5221

That measurement is about 0.9935" (i.e., that last digit is an estimate).

Those measurements would change slightly, of course, using TPMS sensors of different brands. But my point here is that they provide a measurement of the difference:

Check my work, please, someone -- caliper readings and math -- as this seems to be my result:

Using the Chigee stem instead of the stock BMW stem results in 0.9935" - 0.9604" = 0.0331" (0.84mm) of less sticking-out-toward-the-brake-caliper of whatever you put on the end of that stem. That's not much: about three-hundreths of an inch (or less than a millimeter).

I know that a FOBO sensor will smack into a front brake caliper, because I checked it out a couple years ago (and bought a rolling-pin-like stand to be able to rotate the front wheel easily). I don't have a great way of measuring how much the sensor would contact the caliper -- I don't have any other kind of measuring calipers -- but I don't think three-hundreths of an inch is going to make things all right.

If someone has the Chigee sensors and is willing to buy the Chigee stem like I did -- the one supposedly compatible with the jackass placement of Schrader valves on the C 400 GT -- I'd be interested in knowing if the Chigee sensors protrude much less (if at all) than the FOBO gen. 2 sensors.

Hey Bill,

I had to watch a YouTube video on how to read dial calipers before commenting. I’ve only used digital and vernier calipers.

My comments are based on the last 2 photos of your post. You’re using the calipers to measure the bottom of ‘nut’ to the top of the stem with no variable which could affect the measurement.

The BMW stem measures 0.558” or 14.18mm vs CHIGEE @ 0.497” or 12.6mm for a variance of 0.61” or 1.55mm. Referencing my post #12 in this thread the clearance from your front brake caliper to the top of the Chigee TPMS sensor will be 0.638" or 2.27mm. Please keep in mind the wear on my front brake pads will impact the clearance.

I need to apologize first….but I don’t agree with your setup measuring the stem with the TPMS installed. There’s an O-ring inside which will compress affecting your test setup measurements depending on how tight or loose the TPMS sensor is twisted on.

I hope you’re in agreement with my comments.

Have a great day!

 

[wspollack]

Hey Bill,

I had to watch a YouTube video on how to read dial calipers before commenting. I’ve only used digital and vernier calipers.

My comments are based on the last 2 photos of your post. You’re using the calipers to measure the bottom of ‘nut’ to the top of the stem with no variable which could affect the measurement.

The BMW stem measures 0.558” or 14.18mm vs CHIGEE @ 0.497” or 12.6mm for a variance of 0.61” or 1.55mm. Referencing my post #12 in this thread the clearance from your front brake caliper to the top of the Chigee TPMS sensor will be 0.638" or 2.27mm. Please keep in mind the wear on my front brake pads will impact the clearance.

I need to apologize first….but I don’t agree with your setup measuring the stem with the TPMS installed. There’s an O-ring inside which will compress affecting your test setup measurements depending on how tight or loose the TPMS sensor is twisted on.

I hope you’re in agreement with my comments.

Have a great day!

I made a confusing post, with those last two pics. I had originally meant to include them, but then decided to remove them ... but I indadvertently left them in.

Let me talk about those last two thumbnail photos. I had to eyeball the opening of the calipers, because I couldn't put that part of the stem squarely in between the caliper jaws. That is, if the jaws were actually touching those two metal surfaces -- the green-line distance in my post 41 -- the stem would be at an angle between the jaws, not head on (because of the wider diameter of the part that screws into the rim).

So that's why I decided that a more accurate ... squared up ... measurement could be obtained by putting the FOBO on them. Follow me?

I'll grant that my eyeball measurement gave a difference in that green-line distance about twice what the difference was with the FOBO in place, but that's still pretty small. Oh, and I tried to use the same hand-torque to screw on the FOBO, on both stems.

In any case, I'll pass on installing the Chigee stems, as I don't think there'll be enough clearance with or without them. I'll try to think of a way to measure the amount that my FOBO would smack into the front brake caliper side. Maybe I need to buy some more tools, e.g., a vernier caliper of some sort.

In the meantime, I'm still waiting for an answer from the service manager at my local Beemer dealer, regarding whether they'll install the internal sensors on my scoot during the winter service: see https://www.bmw-scooters.com/threads/tpms-programming.3294/ . An expensive proposition, but I've got a burr up my butt now on that project, and want to see it through, if possible.

And thank you very much for taking the time to look over my pics and trying to follow my explanation. Seriously, I appreciate it.

Maybe I should mail you the two stems, and you could do some of your own measurements. Do you have a PO box in the USA, by any chance? I had a friend (who, sadly, passed away this year) from the Montreal area who maintained a PO box in Plattsburgh, NY, so he could buy moto parts in the USA, have them sent there, and drive down periodically. As I recall, he could bring back something like USD 400 worth of goodies without any custom tax. Otherwise, if stuff gets shipped to Canada, it would result in some duty to be paid upon a package's arrival, and that pissed him off no end.

 

[byee]

Hey Bill,

I had to watch a YouTube video on how to read dial calipers before commenting. I’ve only used digital and vernier calipers.

My comments are based on the last 2 photos of your post. You’re using the calipers to measure the bottom of ‘nut’ to the top of the stem with no variable which could affect the measurement.

The BMW stem measures 0.558” or 14.18mm vs CHIGEE @ 0.497” or 12.6mm for a variance of 0.61” or 1.55mm. Referencing my post #12 in this thread the clearance from your front brake caliper to the top of the Chigee TPMS sensor will be 0.638" or 2.27mm. Please keep in mind the wear on my front brake pads will impact the clearance.

I need to apologize first….but I don’t agree with your setup measuring the stem with the TPMS installed. There’s an O-ring inside which will compress affecting your test setup measurements depending on how tight or loose the TPMS sensor is twisted on.

I hope you’re in agreement with my comments.

Have a great day!

Bill,

I sent you a private msg with my address.

Thank you!