Quote:
Originally Posted by FCobra94
That's unfortunate...I was thinking of going with the BFGs after my current DWSs wore out. I had similar balancing issues with these DWS tires too though; it took me having to go through 7 different tires before I found a set of 4 that didn't vibrate.
What road force numbers were you getting from the BFGs? I found that anything over 9 lbs of road force causes noticeable vibration.
|
I did not go so far as to request the rf #'s from the techs. I assumed they had balanced the tires as good as they were able and/or willing to do. Instead of further hassle, I just chose another tire as I still had tire warranty.
You are spot on in your observation that road force numbers of 9+ will result in less than desirable results. Back in the day, my Honda techs had phenomenal success at reducing the road force # by repositioning the tire on the wheel. They would match the high spot of the tire, with the low spot of the wheel. (High/Low referring to heavy/light) This lead to a closer natural balance of the tire/wheel assembly. So much so, that the wheels required little or in a few cases no weights in order to balance successfully.
In fact, most new tires come with a red/yellow/green/orange/blue or white dot somewhere along the face of the sidewall. The manufacturer applies this mark to indicate the heavy portion of the tire. For easy balancing, this should be aligned with the low spot on the wheel. Prior to TPMS this was usually near the valvestem hole on the wheel. I don't know if the additional weight of tmps sensors change this or not... In any event, the wheel can be spun on the balance machine without the tire mounted to find the wheels light spot.
Tire balance is not rocket science. Vibration stems from only a few sources...
Bad wheels
Bad Tires
Bad Suspension components
And the most common, bad technicians.
Sucks to hear about your DWS needing to be replaced so many times in order to get a good set. I have them on my 535i and on my mothers 535i as well. Here, they balanced up very nicely on the first set on the first try.
I can't recall the source, but I recall reading a study stating Michelin tires were delivered with with the fewest # of manufacturer defects. This coincides with what I have experienced in my automotive lifetime. In that study, they stood far beyond the next closest competitor. Dunlop and Continental were below average, even though I have good luck with those brands. I'll dig around and see if I can find that report, though it must be 3+ years old by now...
What's more is that there appears to be quality "grades" of each particular tire. Each tire is measured and tested for design integrity after it is made and assigned the quality grade. The top grade supposedly goes to Car manufacturer assembly plants (BMW, Honda, Gm, etc).
Retailers and resellers are said to receive a lower quality or grade. And I remember hearing of tiers within the retailers too. This may or may not be true, I'll look for my reference here too.