There is always some disagreement over the use or the non use of thread locking compounds. The best known of these is the brand name, Loctite.
Here's a link to some very good information regarding this product > http://motorbicycling.com/showthread.php?t=6957
I came across this card that has some additional info that you might find informative. I personally do not use thread locking products on any engine fastener but I have used the light duty, Blue #242 or the Green #290 on fender brackets and chain guard fasteners. I have no use for the Red #262 on either my bikes or cars.