Hi there ,
initially one of the header pipes would come into a little contact with the front wheel when compressed on the 04 models. I think for memory in Australia they had a replacement header they gave out as it could of been looked at as a potential safety concern I guess. It didn't appear to interfere to much , just marked the header pipe at times under heavy compression from the front tyre.
For memory ,they stopped making that 04 header pipe.
Most of the bikes would have had them replaced by now I would say. The main bearing failures I think were from not setting the end float correctly from factory ,on a first few bikes, here in Aust from what I was told a number of years ago, they were pretty much fixed by checking the end floats I think before sending them out to dealers for the public.
And also on later bikes I would say.
Here in Aust they came out with magura EX handle bars , these had way to much sweep in them, I quickly replaced them with the SX bars which were much better.
Generally they were a good bike, I had 2 04 550 over the years.
Hope this helps some.
