My friend recently bought a Buell XB12s. I went for a test ride on it and the acceleration was very impressive. Now that I am back on mine, I feel like it has lost something. I probably just never noticed because it was gradual, but what are some things that would get worn out? I was debating new plugs, but I only have about 13,000 miles. I thought they were supposed to go a lot longer than that. Also, at about 3-4K on the tach, my bike really lurches when I just cruising. It is very annoying. I have a '98 TLS with a full Yosh system. It has not been reprogrammed. The lurching just started this year. Any tips would be appreciated. The bike still runs great at higher RPM's, just in that little range. Thanks.