Sometimes my chain comes off the big ring. How do I fix that?
This issue is usually fixed very simply with some adjustments.
First, however, let’s look at the bike setup and be sure it is correct:
- Bottom Bracket Installation: Make sure spacers are set according to the crank manufacturer directives — usually none or at most one, 2.5mm spacer on the drive side.
- Front Derailleur Position: See Front Derailleur Adjustment on our support site.
- Chain Length and Tension: It doesn’t directly effect the shift when pedaling, but when coasting or pedaling backward, it with contribute in keeping the chain on the ring.
Once the setup is correct, we can look at adjustments.
Front derailleur adjustment is really important with these chainrings. It should be just a couple mm above the tallest teeth on the chainring for clearance. Rotational position around the seat tube (Toe-in / Toe-out) makes a big difference too. We’ve found in CX, in the rough, the difference between the chain staying on perfectly and some weird issues with chains walking off (inside or outside) is front derailleur position. Please read the set-up directions at https://wickwerks.com/support/maxperformance Note the vertical and toe-in / toe-out instruction.
Make sure the derailleur motion stops are also set correctly. Again, see Front Derailleur Adjustment. Extra space between the derailleur cage outside surfaces and the chain should be minimized.
The chain should be as short as practical given the Big/Big condition. The tension if your rear derailleur allows you to set it, should be as tight as practical.
Chains can make a difference. Shimano and KMC higher-end chains tend to be just a little more flexible side-to-side than the stiffer chains like SRAM. If you’re using SRAM, you might try KMC. Likewise, if you’re using Shimano, you might try SRAM. Different bikes, with different geometries and various derailleurs will act differently.
Check the rest of the drive system for any potential issues — like too much drag in the system — perhaps with the rear derailleur pulleys?
Finally, read the section on cross chaining at WickWerks Support Site These rings should function fine when cross chaining, but as a general rule, it’s not a great idea — especially if your chain has a habit of trouble.