Roadside / Temporary fix for skipping chain

The only ''quick fix'' is to find a gear combination that works and hope for the best. Spending a few pounds on a chain wear checker will save you ever having to be in this position as you can check once a month or whatever and change the chain before it starts eating the rest of your drivetrain.

You could try flipping the chainring around, but that won't help if the primary problem is chain "stretch". If it affects all gears so badly that the bike is unrideable you might be able to split the chain and refit it in single-speed mode (easier with horizontal dropouts - with vertical dropouts or thru-axle you have to hope there's a sprocket that's rideable that provides adequate tension).

Some ideas that might have helped, some

1. Degrease/wipe the chain and chainring and cassette. By removing grease/lube off the outside, it might be a little less slippery.

2. Remove a link of chain to increase the derailleur's tension. You'd need a chain tool and a master link. Risk here is that in larger toothcount gears, you may run out of chain and bust things with leverage, especially if there's an uphill on the way home.

3. If your derailleur has a Clutch, try toggling it on or off, to see which helps most. I suspect ON would be more helpful.

4. Lockout any suspension on the bike that you can. Not common on a road bike, but if this was a MTB then a lockout will prevent bob and give the chain a smoother trip.

5. Pedal in circles - meaning to pedal with smooth easy pressure on the pedal as you roll. No harsh power-strokes, and if you can use your top/lower foot to draw the pedal forward/backward with smooth transitions, that will minimise the Jolting effects on the chain.

Your only other options are to not pedal in some way:

• Get off and stump it home. This can be slow - walking a bike is around 4-5 km/h compared to riding. Will also damage road cleats too, so try to walk on the grass where possible.
• Get off and scooter it. This means to put your right foot on the left pedal, and push against the ground with your left foot, while steering normally with both hands. Your right hip presses against the saddle.
• If you're riding with someone else, you can use the towrope or push. The othes take turns to push your lower back with one hand while they are pedalling, or to pull a towrope - an inner tube works well here. If using a tow rope both of you hold it in your hand, nothing gets tied to the bikes. Or you can grab the belt/waistband/jersey of another rider for a tow to your destination.
• Finally, the Last-Resort Phone Call Of Shame where you ring up home and ask for a pickup, please. I've done this twice in a decade, and all your other options should be tried before this final fallback.

You had the solution with you, and used it.

Double, and even more so triple, chainrings solve a lot. Find a gear that works, ride home or to a bike shop; a new chain might have been better, or might have been worse, depending on the mix of chain- and chainring-wear. There's always a less-worn ring (or sprocket). Where you were lucky is that the less-worn small ring was good enough - because fewer teeth are engaged at once, it needs to be in better condition.

Similarly my rear shifter cable can go from looking good where it always breaks, to "that's funny, I adjusted it recently", to snapping, in half a long ride, say a couple of hundred km. Then I locked off the RD and rode home 200km on a 3-speed, for a rather late night.

Rather than a singlespeed conversion, with vertical dropouts, and if I couldn't get it to stay in gear, but had a lot of flat (so no walk up/freewheel down option) I'd try shortening the chain significantly so the rear derailleur provided more tension, but then you'd need to be sure not to shift much if at all. The extreme version would be to lock off both derailleurs (if thei rlimit screws will do that) or their shift cables, selecting a middling gear, and stretch the RD to the sort of angle you'd see if you were in the big ring and biggest sprocket

Two ideas. I have found increased slipping can be caused by misalignment of the index shifter and improved by adjusting the shifter cable. That is consistent with the problem coming on quickly without time for extra chain wear and easily adjusted back.

And I was convinced my chain was slipping badly recently (also came on quickly) but in fact it was the ratchet pawls in the freehub that were failing. So it may not always actually be the chain. But there's no easy field-fix for the pawls that I can see.