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MRP’s best-selling AMg chainguide is getting a full refresh, adding new features and improved adjustability. Those changes come to the 1x guide for XC bikes, and there’s an all-new GCX 1x chainguide for gravel and cyclocross bikes, too!
Their goal was to create a high performance, quiet chainguide that’s also really easy to adjust and future proof. Here’s how it turned out…
Aimed at All Mountain and Enduro riders, four models of AMg are available, two each in the SL and SLR trims depending on the chainring size they’re paired with…but, now, they both use the same size backplate. It’s only the lower bashguard that’s different. Just swap that out if you move to another chainring range, all without having to buy another guide or remove the backplate from the bike.
The SL models get an alloy backplate ($100 / £110), and SLR is carbon ($160 / £180). Weights from 86g to 109g.
The 1x guide loses the lower bashguard for more XC and Trail use, and comes in ISCG-05 and BB mount. The SL ($75 / £85) and SLR ($100 / £110) options are here, too, with claimed weights from 31g to 40g.
The new GCX Gravel/Cyclocross chainguide ($75 / £80) uses a brazeon mount (add a clamp-on brazeon to your frame if it doesn’t have one). They say it’s lighter and stiffer than previous options for 1x drop bar bikes, and it fits 38- to 46-tooth chainrings. Claimed weight is 29g.
The big improvements come from the 4-way “Forefront” adjustment, letting you bring the guide inboard or outboard, and raise and lower it, to lineup with whatever chainline and chainring you have.
A new inner lining material silences chain slap and rubbing, and it’s shaped to minimize contact even with outlier chain lines measurements and the widest range cassettes.
The other big improvement is the “Pop-Up” feature. Once you’ve got the position set, the guide can pop upward with a firm click, letting you get your chain off for cleaning or replacement, or to swap chainrings easily. Then pop it back down and a firm snap holds it in place where you originally set it.