Tire Balancing & Spinning

Since I was mounting and balancing tires well in advance, I had time to put the bare wheel on the static balancer. For the new rear rain tire I was about to mount on the extra set of wheels for the Kawasaki. The valve stem was truly the heaviest part of the wheel. Typically expected, but now I have confirmation. So I mounted the rain tire with the yellow dot right where the valve stem is located. However it was different when it came time to mount Pirelli SC3’s on the R1. The heaviest part of the R1’s cast magnesium wheels was slightly off from the valve stem. I do have some aftermarket aluminum 90 degree valve stems installed. Unlike the steel ones on the Kawasaki’s wheels. If it were steel ones on the R1, it would probably be right on the valve stem for the heaviest part of the wheel. So, I marked the heaviest part of the R1’s wheels with some tape and a sharpie. Then, mounted Pirelli’s two small red dots to that location. The Kawasaki needed one quarter ounce weight and the R1 needed no weights and this is typically the case for the R1.

I have had the tire spin on the rim of my R1 in the past. Not enough that it threw the wheel out of balance enough to notice on track. You might think, “Well, what the heck? Don’t worry about it.” If you know me, then you’ll know, even still, I want to mount the tire without having it spin on the rim. So I’ve done the complete opposite, I have tried to mount the tire with no tire lube. Doesn’t work. So, I know too much lube allows the tire to spin on the rim and with no lube, you can’t even mount the tire. I’m trying to find the least amount of lube I can use to mount the tire. This time I tried soapy water. I could get the tire to mount, but I couldn’t get the bead to seat on the rim. You know, that “pop, pop” sound as you walk by the tire installation bays at Costco. They say you shouldn’t use more than 42 psi of pressure to get the tire bead to seat on the rim. Some others say you can use a little more pressure. But my pressure gauge was in the yellow (about 55 psi) and I wasn’t comfortable going any higher, closer to the red zone.

Which meant un-mounting the tire and using lube on only the horizontal faces of the bead, not the vertical faces of the bead. This got the bead to seat. This would be, lubing the bead that seats on the barrel of the wheel, not the inside of the outer lip. See images below to help you understand. They are images of an automotive tire, but the concept is the same.

By the time you are reading this I will have known if the tire had spun on the rim or not. Either way its not a danger. If it spins, even a little bit, then it grips for the remainder of it’s time.