[soultrain]

Originally Posted by Ruffles

Well, I played around with my air pressure and this is what I found.

I've always just run my tires around 35 PSI. I don't really know why, I just have. I lowered the pressure to 30 PSI and the vibration got noticeably worse. I looked at the tires closely and could see cupping on the edges. I also noticed that the tire listed the max payload at 50 PSI. I had thought I was riding on the edges of the tires due to the grooves in the road but perhaps what was really just because of under inflation. I increased the pressure to 45 PSI and the problem has almost completely gone away. In fact, when I notice it now, it's hard to tell if it's the vibration / shimmy problem or just an all around section of rougher road.

For those of you with this problem, play with your air pressure. I was amazed at the difference it made.

On a related note, 45 PSI is as high as I've gone so far. Since the tires say the max is 50 PSI, is that where I should be running? I've always thought that the max pressure was just that, a max. For normal driving, it should be somewhat less. What do you think?

If you have cupping then you need an alignment, pure and simple...trust me.