Originally Posted by
MD45
I'm pretty sure Shimano puts threadlock on these bolts at the factory. I've found a red threadlock like film on new shimano derailleur pulley bolts when doing the first maintenance. Regardless, I have used threadlock for years and never had a problem getting the bolts out. I started the practice of using threadlock after a fellow rider lost her derailleur pulley about 40 miles into an 85 mile loop and after searching for 30 min for the bolt, we flagged a car down to give her a ride. You're probably safe without it and I got by for years without it but it won't hurt anything to use it.
I would use the Locktite. I lost the screw on the lower pulley in the middle of the night while bicycling in outback Australia. The RD bent, a spoke or 2 was broken and I had to hitch hike all the next day to get to LBS about 700 (yes that is no typo) km to get to a "L"BS to repair and replace... The 48 spoke wheel was in pretty good shape...
Yup, use the Locktite. You won't have an issue getting the bolt out. I noted "red" pigment on some RDs sold in my LBS, but don't know if it is original Shimano stuff, or some tweak by a bike techie at the LBS.