I am running a 1x11 with a 43t ring in the inner position. This is a regular ring and regular RD, not the new one designed for a 1x setup.

I use two wheelsets, my road wheels are nicely dialed in and I have had 2 chain drops in about 250 miles.
My gravel/offroad wheels, using an identical cassette, drop the chain about every 5 miles. I chalk it up to a slight difference in the hubs.

I do not like having to tweak the shifting when switching between wheels, so I am ready to bite the bullet and put on a bash guard in the outer position.

My other option is I already have an extra 39t ring. So I could put the 39t in the inner position and 43t outside, or vice versa. If I drop chain to the outside I just get another ring, no big deal. But I wonder if the other ring will interfere with the chainline at the extreme ends of the cassette, especially with a 11 speed in back.
On the upside I could do a manual shift and get a 10% lower gear if needed.

Anyone try this?

An outer ring only slightly larger in diameter will not cause any adverse effects. The angular chain rub you're worried about only happens when the outer is much larger than the inner, ie. 53/13. Ideally if you can scrounge up a ring about 6-10t larger, you can cut or file off all the teeth to make a "blank" ring. Then you can file a bit of a bevel on the inside so it's more like a V-pulley, plus have the benefit of not being able to slice your calf.

If by some odd cicumstance you do get some rub on the inside, you can file a bit more off in the inner edge, since you've no concern about shifting up to the blank ring.

Take the teeth off and you have made one yourself. and also a spacer between the crank arm and the Guard will let the chain clear the outer .


the chainline in a 1 By is a bit further out than the inside of a double.. It is Ideal using the Middle of a triple crank as your 1 ring.

aligned with # 6 of 11. center of cassette cluster ..

Or you could, you know... get a device that will shift between the rings for you

The chain is probably dropping because the gravel/offroad surface is rougher. The cassette/hub is not going to make any difference. After trying a few setups on my cyclocross race bike I went with a dedicated chain keeper for my 1x8 setup. Anything else I tried seemed to allow the chain to drop sooner or later and I just couldn't live with that in a 'cross race. IMO it won't look any less pretty than having two rings on a 1x setup.

yep, this is my only 1x, I know how to use a FD
On a recent ride this bike only dropped chain once off road, and I attribute that to landing a bunny hop onto a half buried log. But on the way to and from the trail on nice smooth roads it dropped 4 times, and not just in the 11t but even in the middle of the cassette.

my follow up question is would it be crazy to run the 39t on the outside and use the 43t inside. if the chain drops outside it's not a huge difference in gearing. I don't think I need a proper bash guard, just need to be able to keep going if the chain drops. like so: