Does anyone use a chain guide on their frame?
 

An example is pictured below. If you use one, does it work?

Take it this is the one that stops the chain from damaging the frame when it drops off the small ring. I did try one many years ago and although it did hold the chain away from the frame above the bottom bracket- the chain still wore the paint away underneath the BB.

I am particular about setting the stops on the F Derailler so it cannot happen- it still does occasionally. So to protect the frame- I have put some clear plastic- like thick sellotape- around the area to be damaged.

I use the Third Eye chain guard on my Bridgestone. It works well if you set it up right. It comes in especially handy for compact doubles as they are a little more prone to overshifting, even if you are careful in setting the limiter screws.

Yes, that's the one. I am building up a carbon fiber frame and have seen what a dropped chain can do to CF. I'm thinking about using a chain guide or wrapping part of the frame around the BB in handlegrip tape. Suppose I could do a web search but what is sellotape?

Sellotape is what you call Scotch Tape

I have a Dog Fang on my 1x9 CrossCheck,
also have a Salsa chain wheel disk on the outside.
Never had a problem loosing my chain with this setup.

I put a Deda Dog Fang on my CF after dropping my chain a couple of times to try and protect the CF. It hasn't happened since ... not sure if that is the reason. It was a little difficult to mount because of the thickening radius of the CF as it gets closer to the bottom bracket.

Yes, I have one on my rain bike, haven't dropped a chain since installing it. Set it up so it almost touches the inner chain ring.

The N Gear Jump Stop is a popular choice among the single speed crowd.

That was likely a follow-up question I would going to, er, follow up with. The guides come in different sizes. Like your frame, mine gets thicker (larger diameter) closer to the bottom bracket. What is the positioning of the chain guide? The "hook" part (fang) at the level of the teeth of the small chain ring, or below or above? Any info appreciated.

Saw this one as well when I was looking at the chain guides on different sites, which said this model doesn't work with ovalized frame tubes. Thus, I guess, its popularity with the single speeders.

The 3rd Eye Chain Watcher may be more adaptable to a varying diameter tube. Fits 1-1/8" to 1-3/8" round or oval seat tubes.

My tandem came with one. I don't know if it works or not, but at least it hasn't hurt anything. :)

My bike actually came with one of these on it (Specialized Sequoia), but I didn't even realize it was there until I dropped my chain a couple of times and was wondering what to do about it. Turns out the thing was not positioned correctly. I did a major drivetrain overhaul and adjustment recently, so we'll see how well it works in a couple of months.

Use this on all my bikes.....once set up properly, ends all chain jumps off the inside. Will handle a little bit of ovalizing on the tube because the mount is a soft plastic but not a lot.

My mountain bike has a Sharkfin, which evidently serves the same function.

I put one on my Scott CR1 SL as an insurance policy. I have the Deda in a large size. Don't know actual diameters available.

Never used one, but do you NEED one if the bike's set up properly? I've only had the chain slip off very occasionally (like maybe four to six times in 30+ years of riding), and it's always been because I'd been sloppy in the derailleur adjustment.

No, you don't really need one. But it can be good insurance against the occasional slip up. I put mine on when I got a custom paint job. I didn't want to risk it.

On a regular double setup, you would rarely need it. On a triple, the chance of the chain falling off the inner ring is a little greater. On a compact double, it is greater still. On a single speed <edit>(or 1 X 7,8,9,whatever)<edit>, especially one used offroad, it can be pretty useful.

The frame on my rain bike has the RD cable guide brazed to the top of the BB shell. When the infrequent chain drop occurs, the chain sometimes gets jammed between the cable guide and the granny ring which can be a real pain to free up...especially in the rain. It's not simply just a matter of lifting it back up onto the chainring.

The FD is adjusted properly but still isn't perfect 100% of the time.:)