I recently bought a Raleigh Alyeska (1985 I think). It's an excellent bike, but the some of the outer gears slip or do not shift properly. I'm used to a Shimano rear derailleur which has the tension screw to adjust slipping, but I don't know much about the derailleur on this bike. It's a Suntour XCD 6000 7 speed. I understand what the H and L screws are for, but not too sure what the A<-->B setting is for. The A<-->B setting is under the H and L screws (see attached picture). Also there is a setting on the shifter, there is a UL, P, and RE setting. I have attached pictures of the rear derailleur and the shifter. Any help would be awesome!
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