My question is kind of techinical in nature. OK, I needed a new chain on my trek 5200. Now I believe it was a shimano HG that was on it. The bike shop siad they did not stock shimano parts because they were too expensive. So the manager said he had one that would fit, and I believe it is a wipperman. I got it home and have ridden it a few times. It shifts better, but now it feels like this chain is too wide and binds in the back and has fallen off the front small chain ring twice when shifting. I have taken it back and the lbs insists that it is the corect(same size as shimano hg chain) and that their is nothing wrong with it. It will shift fine when there is no load on it, but when racing and the chain drops off, it is really pissing me off. It feels like the chain is too wide, and there is plenty of play from side to side, or way more than shimano. Any help would be great.
It sounds as if this may be as simple as adjusting the inside limit screw on the front derailleur so there is less travel.
The play from side to side is probably responsible for the better shifting.
Wipperman makes quality chains every bit as good as Shimano. Your LBS probably knows which is the correct chain to replace the Shimano. This is pretty simple information that the chain manufacturer supplies the bike shop with.
I don’t doubt that they installed the correct chain. Remember, the old chain got longer as it wore. You may have made some small adjustments to your derailleur cables as you rode your bike to accommodate this wear.
Lastly, as the chain wears, so do the cassette cogs and chainrings wear as well. If you delayed chain replacement way beyond what is recommended in terms of chain wear (lengthening) then you can cause excessive wear to your cassette cogs and chainrings. This wear to your chainrings and cassette cogs can then become responsible for poor shifting and skipping/jumping gears after installing a new chain. Excessive wear to your cogs and chainrings will result in the gear teeth having the appearance of shark teeth rather than symmetrical hills/mountains.
This is one of the best reasons to accurately measure chain wear regularly rather than to rely on a mileage formula for replacing your chain. You will greatly extend the life of your gears by doing so.
Chain wear is greatly influenced by the rider, terrain, conditions, etc. such that mileage formulas often result in causing excessive wear or premature chain replacement.
If you are interested in getting up the learning curve on chain maintenance/wear and drivetrain performance, you may want to check out Sheldon Brown’s website. It will certainly help your understanding of how your chain, cogs and chainrings work in tandem to help propel you forward and what adjustments may be called for to improve your shifting performance when things aren’t quite right.