Yellow dot and valve stem alignment

Status
Not open for further replies.
Originally Posted By: CapriRacer
Just so everyone understands:

The issue with the dots being aligned with the valve stem is NOT about balance. It is about uniformity (Think "roundness" and you will be close.) The idea is to make the assembly as round as possible and NOT to reduce the amount of balance weights needed.


In some cases it is about balance.

Check out the link I posted above. Sumitomo says they have two marks on their tires, which includes a yellow mark for balancing purposes. They also include a red mark that is for the runout purposes you describe.

Quote:

The Balance Marks will be indicated as follows:
Yellow - Within 3 inches to either side of the YELLOW circle is the LIGHT spot of the tire. Each
tire is confirmed at the factory for radial balance, and marked at this point. For most mounting
practices, Sumitomo suggests mounting this YELLOW circle near the valve stem, and use of
industry recommended procedures for safe tire mounting.

Red – A RED circle denotes a measurement of high-speed run out (measurement called
HARMONIC). If the wheel/rim is an OE spec rim, it is marked at the factory with a DIMPLE (in
the rim/wheel heel). If this tire/rim assembly gives a vibration at high speed with the YELLOW
circle at the valve stem and the bead is checked for proper seating, then the RED circle should
be matched with the DIMPLE.


In Yokohama's case, the situation is the same. They include a uniformity marking and a weight marking:
https://www.yokohamatire.com/tires-101/advanced-information/match-mounting

Quote:
When performing weight match-mounting, the yellow mark on the tire, indicating the point of lightest weight, should be aligned with the valve stem on the wheel assembly, which represents the heaviest weight point of the wheel assembly. After match-mounting by either of the above methods, the tire/wheel assembly can be balanced.
 
Originally Posted By: stephen9666
In some cases it is about balance.......


Thanks and sorry for the large truncation, but there isn't any point in repeating the post.

- BUT -

That was truly AMAZING!! I spent 5 years in this area, and what was written is totally wrong. It's no wonder that people are getting this wrong. This has always been about uniformity and never about balance. I am struggling to understand how Sumitomo and Yokohama could allow this misinformation to stand uncorrected.

And just so everyone understands, the yellow dot on the tire information is very likely correct. It is the valve hole on the wheel information that is not. IF the valve hole marks anything (and it sometimes doesn't), it will be marking the radial first harmonic low point of the runout, which is not the light spot of the wheel.
 
Last edited:
90 grams of weights from the Ford factory.

90-grams-of-wheel-weights-from-factory.jpg
 
It can take a lot of tape weights, compared to the standard clip on weights. If the balancer calls for 1 ounce of clip on weight on the flange, when you move inside the wheel it can take 2 ounces or more with tape weight because it is further away. And, that usually causes the inboard weight to change too, and call for even more weight.
 
Originally Posted By: CapriRacer
Just so everyone understands:

The issue with the dots being aligned with the valve stem is NOT about balance. It is about uniformity (Think "roundness" and you will be close.) The idea is to make the assembly as round as possible and NOT to reduce the amount of balance weights needed.


This is an interesting thread because I searched for this very subject after talking with a Toyo technical representative earlier today. Toyo tells me the yellow dot represents "the tire's light balance point" so I guess they don't read our threads here
shocked2.gif


I guess if it is about uniformity then the relationship with the valve stem would make no difference. If is about "the tire's light balance point" then it would be preferable to mount it near the valve stem.

Yokohama, Sumitomo and Toyo all seem to be in the "the tire's light balance point" camp - it does make one wonder why they all support this idea without reference to uniformity? How about they only have H-1B visa engineers ?
 
Originally Posted By: Cressida
Originally Posted By: CapriRacer
Just so everyone understands:

The issue with the dots being aligned with the valve stem is NOT about balance. It is about uniformity (Think "roundness" and you will be close.) The idea is to make the assembly as round as possible and NOT to reduce the amount of balance weights needed.


This is an interesting thread because I searched for this very subject after talking with a Toyo technical representative earlier today. Toyo tells me the yellow dot represents "the tire's light balance point" so I guess they don't read our threads here
shocked2.gif


I guess if it is about uniformity then the relationship with the valve stem would make no difference. If is about "the tire's light balance point" then it would be preferable to mount it near the valve stem.

Yokohama, Sumitomo and Toyo all seem to be in the "the tire's light balance point" camp - it does make one wonder why they all support this idea without reference to uniformity? How about they only have H-1B visa engineers ?


The idea of balancing a tire is so ingrained in people that it is a hard concept to get out of people's heads. I've had to explain to otherwise knowledgeable people about the dots and their relationship to unifomity and balance.

And just to be clear, it is quite possible that Toyo, Yokohama, etc., do use a yellow dot for the balance light spot. There is no agreement on how this is to be done. Hopefully I explained above that even the OEM's (Ford, Toyota, BMW, etc.) do not agree on how to mark the uniformity high point on a tire (and the uniformity low point on the wheel) - so how can the tire manufacturers be expected to be the same.

Which brings me back to my web page Barry's Tire Tech: Vibration - Balance, Runout, and Uniformity

If any of you are talking to someone else from a tire manufacturer (or anyone else who doesn't get the thing about the dots), have them read that page. They can even email me at the address listed in the header if they have questions.
 
Originally Posted By: CapriRacer

And just to be clear, it is quite possible that Toyo, Yokohama, etc., do use a yellow dot for the balance light spot. There is no agreement on how this is to be done.


This is what I was pointing out in an earlier post in this thread.

I just want to note this part specifically for anyone reading this thread, since previously you argued those manufacturers were "totally wrong" when they said it was about balancing.

Originally Posted By: CapriRacer
That was truly AMAZING!! I spent 5 years in this area, and what was written is totally wrong. It's no wonder that people are getting this wrong. This has always been about uniformity and never about balance. I am struggling to understand how Sumitomo and Yokohama could allow this misinformation to stand uncorrected.


I think probably the takeaway from this thread is that a tire buyer or installer may need to consult the specific tire manufacturer when it comes to the dots. Clearly, some companies producing tires say they're using some of the dots to mark a balance point, not necessarily a uniformity point.
 
Originally Posted By: stephen9666
Originally Posted By: CapriRacer

And just to be clear, it is quite possible that Toyo, Yokohama, etc., do use a yellow dot for the balance light spot. There is no agreement on how this is to be done.


This is what I was pointing out in an earlier post in this thread.

I just want to note this part specifically for anyone reading this thread, since previously you argued those manufacturers were "totally wrong" when they said it was about balancing. .......



I'm afraid you misunderstand.

First, the tire manufacturers may actually be using a dot for a balance location, but the wheels aren't marked for balance. If anything, they are marked for runout - and sometimes that mark is the valve hole. Since balance and uniformity (runout) are completely different things, matching them up doesn't help with balance at all - except coincidentally.
 
Originally Posted By: CapriRacer
Originally Posted By: stephen9666
Originally Posted By: CapriRacer

And just to be clear, it is quite possible that Toyo, Yokohama, etc., do use a yellow dot for the balance light spot. There is no agreement on how this is to be done.


This is what I was pointing out in an earlier post in this thread.

I just want to note this part specifically for anyone reading this thread, since previously you argued those manufacturers were "totally wrong" when they said it was about balancing. .......



I'm afraid you misunderstand.

First, the tire manufacturers may actually be using a dot for a balance location, but the wheels aren't marked for balance. If anything, they are marked for runout - and sometimes that mark is the valve hole. Since balance and uniformity (runout) are completely different things, matching them up doesn't help with balance at all - except coincidentally.



You're also misunderstanding.

I'm not trying to start an argument. Simply pointing out that the dots can in fact be a balance point.
 
Originally Posted By: CapriRacer

First, the tire manufacturers may actually be using a dot for a balance location, but the wheels aren't marked for balance. If anything, they are marked for runout - and sometimes that mark is the valve hole. Since balance and uniformity (runout) are completely different things, matching them up doesn't help with balance at all - except coincidentally.


I get it now. The public, and apparently many who work in the tire business, have believed that the valve stem represents the heavy portion of the wheel. We have an unfounded picture of a perfectly balanced wheel before the valve stem. Then after the addition of the valve stem (which adds a small amount of extra weight at that location) it was assumed this would be the heavy part of the wheel. However, since the wheel may have never been in balanced before the valve stem and the wheel manufacturer employees didn't even consider balance when placing the valve stem location, it was all a false belief.

The tire manufacturers aren't helping any by publishing and advising that their "dot" is the balance light spot. That information is next to useless unless one knows the wheel's heavy spot - and we just don't have that without testing, which very few shops would ever take the time to do, and it probably doesn't change or help with the end results anyway.

The bottom line for me: This appears to be a case when ignorance was indeed blessed...
 
sadly most people do not know that the dots are supposed to line up with the stem
Even my local ford dealer is too stupid to realize this when I asked about it.

However a good balance job will still do fine if the job if done right
 
Originally Posted By: Excel
sadly most people do not know that the dots are supposed to line up with the stem
Even my local ford dealer is too stupid to realize this when I asked about it.

However a good balance job will still do fine if the job if done right


Not exactly.

First, if the dots represent only the heavy (or light) spot of the tire, lining up the dots with the valve stem doesn't do anything of value. The good news is that it doesn't do any harm, either.

Second, if the dots on the tire represent the uniformity high point, then matching that dot with the valve stem only does good if the valve stem marks the low runout point for the wheel - and that is not a sure thing.

PLUS, all the vehicle manufacturers require the tires to be marked for uniformity (wheels, too!) and there is no standard way of marking either - so they think it is more than just balance. Don't get me wrong - balance is important - but it isn't the only thing.
 
Just received (2) New motorcycle tires today for my XR650R which is plated.
Both new tires have a yellow dot.
So do I line the dot up with the valve stem, the rim lock , or in between.
Don't mean to hijack thread.
 
Originally Posted By: ottomatic
Just received (2) New motorcycle tires today for my XR650R which is plated.
Both new tires have a yellow dot.
So do I line the dot up with the valve stem, the rim lock , or in between.
Don't mean to hijack thread.


I don't think what we have been discussing above applies to motorcycle tires. It's even possible the dots have nothing to do with balance or uniformity and perhaps just an indicator that the tire has passed through certain processes.

So I would suggest that you contact the manufacturer to find out. Be sure to mention that these are on a motorcycle tire.

Alternatively, you could mount them such that the dots on the tire match up with the valve hole since that is what passenger car tires do (except the dots are frequently red). There isn't going to be any harm done if you do this, it just might not be the best.
 
Status
Not open for further replies.

Similar threads

GON
Metal vs. Rubber Valve Stems video
Replies
5
Views
601
pzev
S
Sam's Tire Center damaged valve stem they installed
Replies
5
Views
859
NormanBuntz
1 SX
Can I use anti-seize on metal TPMS valve stem threads?
Replies
8
Views
2K
Sequoiasoon
skyactiv
I bought grey market tires for my VW
2
Replies
26
Views
2K
edyvw
V
A PSA About those tire TINS and date codes: Installers, It's Dates Out, for ALL tires.
2 3
Replies
47
Views
3K
CapriRacer
Back
Top