Yellow Dot on Tire - Heavy or Light Spot??

BonesDT

Member
I'm being uber anal so I need a confirmation on this:

I'm mounting Dunlop Q2's. From Dunlop Moto's site:
"All Dunlop street tires should be installed with the yellow balance dot at the valve."

However, I put my wheel (no tire) on the balancer and the valve is neither the heavy spot nor the light spot. I've searched all over online, but some say the valve is suppose to be the light spot because metal from the wheel was removed for the hole - however, others say manufacturers casted the wheels to compensate for that and made it heavier where the valve hole would be. I would think the valve would be the heavy spot because a valve seems like it would be heavier than a tiny metal donut hole.

Whatever it is, I know in my case the yellow dot on the valve would not be ideal. I'm just trying to figure out what Dunlop's intentions were.

Is the yellow dot the heavy spot on the tire so it should line up with the light spot on the wheel or vice versa? Thanks.
 

dbarufaldi

Member
Here's what I've read:

Yellow dot is light spot (balance) on tire. When there is a yellow and a red dot, the yellow is the light spot (balance), the red is the high spot (roundness).

Conventional wisdom was that the dot goes next to the valve, but I think, if you know your wheel is heavy somewhere other than the valve, it should go there.

Dan B
 

Sklossmonster

New Member
The yellow dot is theoretically the lightest point around the tire. The valve stem is theoretically the heaviest point around the rim. Therefore you "should" mount the tire so that the lightest point of the tire (yellow dot) is at the heaviest point on the rim (valve stem, especially metal ones) to minimize the imbalances inherent in the manufacturing processes.

In reality, however, some manufacturer's tires are more balanced than others, and the dots don't always line up with the actual lightest part of the tire. Similarly, the valve stem is rarely the heaviest part of the rim.

If you want to be super anal about it, (like I used to be) you can put your wheel on the balancer with no tire on it. Let it settle, then mark the heavy spot for yourself, which will of course be at the six o'clock position on the balancer, usually a few inches from the valve stem one direction or the other.

Once the true heavy spot on the rim has been determined, now at least half of the error has been eliminated, and you can use less weights when you balance your tires by aligning the yellow dot to the true heavy spot on the rim.

And yes, I am a freak.
 

BonesDT

Member
I just found this:
http://www.bridgestonetrucktires.com/us_eng/real/magazines/ra_v13_i1/PDF/ra_v13i1%20ask%20doc.pdf

This article says the yellow spot marks the lightest spot of the tire. It says the valve stem (of aluminum wheels) is the heaviest spot. One of the pics shows the valve matched up with the yellow dot on steel wheels, so it implies the valve is also the heaviest part of a steel wheel (I have alloys).

But here's where I doubt this article. I don't have red dots so I shouldn't worry about it, but I read it out of curiousity. It seems to contradict itself. Basically it says you should line the red dot with the light-point dimple, and if the light-point dimple isn't there, then line it up with the valve (the heavy point)???

Why is the heavy spot (valve) an alternative to the light point (dimple)? Unless they are trying to say mach the red dot with the light-point for steel rims but the heavy point for aluminum wheels???

My valve is no where near the heavy or light spot. It is almost smack in the middle, but it leans towards the heavy side slightly. I balanced the wheel without any valve and then with a valve (Kurvey Girl's aluminum 90-degree valve). The valve itself seemed to make very little difference in weight.

I'm just trying to figure out where to line up the yellow dot. Obviously the valve is not the right location in my circumstance. If I get it wrong, then instead of having a near balanced tire before real balancing, I'm going to have a very unbalanced tire that needs to be corrected!
 

BonesDT

Member
OK, it seems most people agree tire manufacturers intend the yellow dot to signify the light spot on the tire (so the tire manufacturers' position is that the valve is theoretically the heaviest part of the wheel).

I was just studying the No-Mar Video. The guy just said line the red dots (Pirelli) with the valve, and if you want to be really accurate, balance the wheel, and line the red dots with the LIGHT spot.

There is a lot of misinformation out there.
 

BonesDT

Member
BonesDT;127311 wrote: But here's where I doubt this article. I don't have red dots so I shouldn't worry about it, but I read it out of curiousity. It seems to contradict itself. Basically it says you should line the red dot with the light-point dimple, and if the light-point dimple isn't there, then line it up with the valve (the heavy point)???

Why is the heavy spot (valve) an alternative to the light point (dimple)? Unless they are trying to say mach the red dot with the light-point for steel rims but the heavy point for aluminum wheels???
Sorry. The article does not contradict itself. I re-re-re-read it. The dimple is "low" point. Low meaning heavy. I confused my L-words.

OK, enough of the anal dimple dot L-words, I'm mounting this bad boy so I can go for a ride already! Thanks for the help.
 

Sklossmonster

New Member
Keep in mind the differences between the heavy and light spots can be easily counterbalanced with wheel weights, that's what they're for ;)
 

jtsgsxr6

Member
My two cents is that with bridestones that I use I always put the yellow dot with the actual heavy spot of the wheel, and I usually don't need much balance weight by using that method. Untill I find a reason to change my method I'll stick with it.
 

JRSMAIL

New Member
I say your going to balance the assembly anyway so who cares. I've mounted dot lined up and many times not, I'm still balancing the assembly.
 

Mikey75702

Member
I haven't mounted or balance motorcycle tires, but I do light/heavy truck and bus tires all the time. Always mount the tire with the DOT matched to the valve stem and always uses very little weight to get balanced. Have had tires where someone else mounted (new tire) and it was taking alot of weight, so I broke it down, spun it to align dot and valve and used alot less. This may or may not be the case with Bike tires though
 

BonesDT

Member
Damn, I overinflated to probably around 60 psi while seating the beads (max 42 psi). I wasn't paying attention. Is this bad?
 

FaceRace98

New Member
Your fine man, just set it to the correct pressure and go ride...

How did the tire patentend fo-mar mounting rig work for ya?
 

BonesDT

Member
Er, not too good, but I expected that for my first time. I did the front yesterday, is the rear going to be easier or harder?

The table I mounted the set-up to is too light and spins, but it's all I have to drill a hole in. I had to have someone bear hug its legs while I mounted. I also doubled up duct tape and stuck it between the table & 15" car rim and between the moto rim and the car rim to prevent spinning. Also, I think your post said use a 3/8" threaded rod, but that's too flimsy, I bent it pretty good. Maybe you meant 3/4", but my front axle would need 7/16". Maybe I didn't use enough lube, I didn't want to use too much.

No-Mar had a special during the winter where they threw in their Yellow Thing with the bar. They didn't have the special anymore and I called to beg them to throw it in, and they wouldn't. $36 for it! So I made one with a tiny c-clamp drenched in duct tape. I wish I had tons of money and could buy all their tools and accessories, tire changing would be soo easy & fun.
 

ERB68

New Member
First, bolt the no-mar to a 4X8 sheet of 3/4" ply wood. Stand on the ply wood when mounting.
If garage space is a big issue(as it is for me) get the trailer hitch mount.

Second get the yellow thingy. I know the price is a turn off but once you have it you will not mind the price. When using the yellow thingy, sometimes the tire will fight with you to get the last quarter of the tire on. Take the yellow thingy off and this last bit will go better.

Rear tires are easier, the more side wall the easier it is to flex it on to the rim. If you have any friends with Harley's and they have the 21" front wheel DON'T change tires for them.

Be sure to wipe off any soapy water from the rim before mounting the new tire. The water will drive you crazy when trying to balance.

When mounting, be sure to use the paste lube. Watch the video carefully on where it needs to be. It makes it a lot easier if you have the right parts of the tire well lubed.
 

dbarufaldi

Member
BonesDT;127314 wrote: Sorry. The article does not contradict itself. I re-re-re-read it. The dimple is "low" point. Low meaning heavy. I confused my L-words.

OK, enough of the anal dimple dot L-words, I'm mounting this bad boy so I can go for a ride already! Thanks for the help.
Well, re-re-re-re-read it again. The dimple is for a low spot, which isn't the heavy point, it's the low spot in terms of roundness. That's way you align the red dot on the tire with the dimple of the wheel. The red dot on the tire is the high spot - high in terms of roundness. Doesn't refer to weight at all. Yellow is the weight dot, indicating light spot.

I think most moto tires don't mark the high spot, but could be wrong about it....

Dan B
 

BonesDT

Member
ERB68;127375 wrote: First, bolt the no-mar to a 4X8 sheet of 3/4" ply wood. Stand on the ply wood when mounting.
If garage space is a big issue(as it is for me) get the trailer hitch mount.

Second get the yellow thingy. I know the price is a turn off but once you have it you will not mind the price. When using the yellow thingy, sometimes the tire will fight with you to get the last quarter of the tire on. Take the yellow thingy off and this last bit will go better.

Rear tires are easier, the more side wall the easier it is to flex it on to the rim.
Unfortunately, I don't have the No-Mar changer machine, just the mount/demount bar. I used FaceRace's ghetto set-up - but more ghetto as I don't have a heavy table to mount it to, so I just tied my girlfriend to the coffee table legs. Just did the rear tire - sooo much easier!

dbarufaldi;127378 wrote:
Well, re-re-re-re-read it again. The dimple is for a low spot, which isn't the heavy point, it's the low spot in terms of roundness. That's way you align the red dot on the tire with the dimple of the wheel. The red dot on the tire is the high spot - high in terms of roundness. Doesn't refer to weight at all. Yellow is the weight dot, indicating light spot.

I think most moto tires don't mark the high spot, but could be wrong about it....

Dan B
Oops, my bad. Oh well, I just had yellow dots on mine anyway. My front wheel took 35 grams to balance (five 1/4oz weights). Seemed like a lot since I went anal on the lining the yellow dot up. I'm balancing the rear wheel right now. The Harbor Freight $60 balancer is pretty nice and seems very accurate.
 

FaceRace98

New Member
BonesDT;127355 wrote: Er, not too good, but I expected that for my first time. I did the front yesterday, is the rear going to be easier or harder?

The table I mounted the set-up to is too light and spins, but it's all I have to drill a hole in. I had to have someone bear hug its legs while I mounted. I also doubled up duct tape and stuck it between the table & 15" car rim and between the moto rim and the car rim to prevent spinning. Also, I think your post said use a 3/8" threaded rod, but that's too flimsy, I bent it pretty good. Maybe you meant 3/4", but my front axle would need 7/16". Maybe I didn't use enough lube, I didn't want to use too much.

No-Mar had a special during the winter where they threw in their Yellow Thing with the bar. They didn't have the special anymore and I called to beg them to throw it in, and they wouldn't. $36 for it! So I made one with a tiny c-clamp drenched in duct tape. I wish I had tons of money and could buy all their tools and accessories, tire changing would be soo easy & fun.
Yeah i could see where a light table would be a problem, you need a good amount of force to put the tires on.

To keep the car rim from spinning on the table you can go to lowes and get a U shapped bolt (not sure what its called) and put it through the rim, drill holes in the table and bolt it on the bottm. This will securley fasten the rim to the table.

I think it is a 3/4" rod... sorry man. I bought the thickest one they had. Make sure its sticking out a good bit on the bottom of the table, you really don't need it to stick out too much on top, just enough to lever the bar on.

Usually i put a light coat of lube on the tire lip and put it half way on, then go back and re lube the last half remaing as well as the underside of the tire, it can be a bitch ir theres not enough lube on there... If you put too much the tire can spin on the rim thats why I only apply a light coat at first.

Hopefully it wasn't too much of a bitch getting them on with the ghetto Fo-Mar setup. Once you do it a couple times and get a hang of it, it gets easier to use. It's a good feeling to look at the fresh tires you mounted knowing you saved $40-60 without having to buy a tire machine.
 

vtjballeng

New Member
JRSMAIL;127326 wrote: I say your going to balance the assembly anyway so who cares. I've mounted dot lined up and many times not, I'm still balancing the assembly.
More weights = more vibration due to dynamic / lateral (side to side) imbalance caused by weights that are not along the centerline axis. High end dynamic balancers try to deal with this but it is simplest to minimize he need for weights as most racers don't have the tires dynamically balanced.
 
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