Originally Posted by myk_edwards
My 2001 LT is running Storms, and very happy with them, my buddy who rides a 2004 is being told by local dealer not compatible with 2004 and newer LT??
Why? the newer bike is close to 50Lbs lighter, is he just reading some out dated rubbish in a tyre compatiblity chart? Saving over other makes, Bridgestone, Metz, is close to £50.
I researched this a few years ago and actually got a reply from an Avon representative.
Apparently the change in steering geometery with the 2005 model creates an increased risk for instability with radial tires. BMW stopped putting radial tires on the K1200LT (radial Bridgestones were OEM fitted on some of the early bikes, including my 2000).
Both the tire manufacturers and BMW say don't put a radial on a post-2004 K1200LT.
Instability is influenced by a number of factors like road surface, temperature, tire wear, inflation, wheel balance, etc. Many folks will report "no problems" with various tire combinations like mixed bias and radial, mixed brands, or running radials on a bike that the tire manufacturer says isn't "proper fitment" of their tire. In my experience, instability, head shake, tank slapper, wobble, or whatever you want to call it, happens unexpectedly. It is possible to ride thousands of miles, become very comfortable and confident, and then suddenly get spanked severely.
I figure the tire manufacturers know more than I do about it and I've decided to follow their recommendations. But that's just me, we all choose our risks, so to each their own.
Here's a summary from a thread I posted to a little while ago: