I have just turned my bike upside down and shifted through all of the gears. While being in the middle front ring and in the biggest rear ring i had scrubbing against the front mech and i had the upper jockey of the rear mech touching the biggest cassete ring.
Is this normal?? XT Mech ,LX cassete,Rockhopper 2003 frame.
Also would it be usefull to clean the chain with petrol as i used to do in old times in order to remove the sticky factory grease? and then relube it with winter chain lube.