While it is technically possible to run an oval or elliptical chainring with your TRS or LG1 Chainguide the chain retention capability of the guide is diminished. This is is due to the gap which opens at the slider location as the narrow part of the ring passes thru the slider.
One should also note the max ring capacity of the chainguide will not be the same as when running a round ring. A guide with a 34t max capacity may only be able to accomodate a 30 or 32 tooth ring depending on the profile of the ring./hc/en-us/articles/360045320492-Can-I-run-an-oval-or-elliptical-chainring-with-my-chainguide-
Click below to download/hc/en-us/articles/204752855-International-standard-chainguide-mounting-ISCG-specs
For most of our guides the backplate is the bulk of the cost of the guide, so we don't offer replacement backplates for all guides. Check your guide's service parts diagram to see if backplates are available for your guide. In some cases it may make sense to get a new complete guide./hc/en-us/articles/204128579-I-got-a-new-frame-with-a-different-ISCG-standard-can-I-replace-just-the-backplate-of-my-current-guide-rather-than-the-whole-thing-
It’s no secret we make chainguides - accordingly, we are pretty enthusiastic about keeping chains on. For the best chain retention with a minimal weight penalty, we still recommend a guide with an upper slider like our TRS+ guide, narrow-wide notwithstanding.
As a new drive train ages, several factors can reduce the retention capability of the narrow-wide rings including chain wear/stretch, ring wear, and rear derailleur clutch friction deterioration or failure.
For everyday riding, narrow-wide rings like our UL, SL and Helix direct mount rings provide an exceptional level of chain retention when used with a clutch derailleur. Come race day, a 70-150g weight penalty for a chainguide is a small price to pay for absolute peace of mind./hc/en-us/articles/204775205-Do-I-still-need-a-chainguide-if-Im-running-a-narrow-wide-ring-and-clutch-derailleur-