Originally Posted by
cigartrader
I picked up a chain skipping problem on this bike with the smallest sprocket. Is there an adjustment on the suntour to tighten the tension? It looks like there might be, there's a cover over the spring with a screw on it. It looks like maybe you and spin it to tighten the chain up.
Chain skipping is not normally due to chain tension.
1. Ensure the derailleur's outward travel screw is properly set so that the jockey pulley is lined up with the cog.
2. Ensure it is not a stiff chain link. Mariginally stiff links will be noticeable on the smallest cog because the chain wraps tighter around it. Put the bicycle in a stand and pedal slowly. Place a mark on the skipping link. If it always skips on the same link, grab the chain on both sides of the offending link and flex the chain lateraly to loosen the link.
3. Ensure it not a damaged or worn cog. Lots of owners were intimidated by derailleurs, but wanted to own one to be in fashion. They would ride the bicycle without changing gears, usually in the small cog. Consequently this cog received all the wear. When a new chain is installed it works properly on the other, unworn cogs, but skips on the worn, small cog. If it skips on the small cog in both the large and small chainrings, it is not chain tension.
4. I haven't taken apart a SunTour derailleur of that era to determine if the cage tension can be adjusted. It can be done with their earlier derailleurs. However, it is far easier and faster to remove links from the chain than to disassemble and reassemble a derailleur.
FYI, I don't know if I mentioned this before but your Riviera is actaully a 1985 model that was built in 1984.