spelger

i recently changed my chain, first time, and it was relatively easy. new chain has a quick link. it did not appear that i needed to make any shifting adjustments until i rode with it. for the most part it shifted fine when going from the middle to the large chain ring. it dropped once on that first ride and i chalked it up to stuff happens. the second time it happened i noticed that the quick link was in the vicinity. third time and again there was the quick link. forth time too.

finally had a chance to make some adjustments and before doing anything i got it to drop once again, the quick link was not there. made adjustments anyway then put her on the trainer and shifted a bunch of times with more stress on the chain. seemed to shift just fine.

today it dropped again and don't you know it the quick link was there again.

this is my first chain with a quick link and i have a suspicion that there is a relationship with the chain drop and the quick link. i;ll be making some additional adjustments to the FD but am wandering from experienced wrenches if there is something i should be looking for when i do.

thanks,
scott

Andrew R Stewart 

The first thing I note is the comment about shifting the front under stress. When shifting the front der stress/pedal pressure IS NEVER a good idea. Where did you get the idea is was a good way to do this? Andy

spelger

its funny, right after i posted i debated about making that clear (it was a quick debate). when testing shifting on the stand i can never really simulate the sort of shifting while peddling, cranking by hand is just not the same. so, when i mean that i added stress while on the trainer it is more stressful than by hand but not so much that it would cause grinding which i know is not good. probably not clear but i think you get the idea.

-scott

Andrew R Stewart 

Scott I do get that, every day at work I talk about this. That so many people have a hard time actually doing the "soft pedaling" thing is why the industry is moving away from drivetrains with many well spaced gears to those with fewer gears with larger gaps between then (1x). And market this as an improvement

I post for not just the OPs but also the readers who try to see their issues in others' OPs. So when i read of stress being applied to a system that is designed to not work well with such I feel the need to call it out. I think you get my idea.

To reply to the jist of your post, the connecting link being the reason of chain drop. Sure/maybe/sort of/depends. The connecting links don't usually have the same link plate shaping or lateral flex that all the others do. so that could contribute. But I'l, say that so many others find this to not be a problem with so many bikes for so many collective miles that the stats are not agreeing with your experience. Of course one test would be to change the chain to one that uses a specific reassembly pin, and not a connecting link. But then the rest of the chain might also be different so not a good single change test. Andy

MudPie

My experience with quick links (SRAM and KMC) is all positive. I've been using chains with masterlinks for over 20 years and i cannot remember the last time I dropped a chain.

1. When you say drop your chain, is that the chain falls between the small chainring and frame?
2. When you put on the new chain, did you shorten it to match the length of the original chain?
3. I'm not sure I follow when you say you drop a chain and the quick link is there. Do you mean the link is positioned and laying on top of the bottom bracekt.

spelger

OK, quick link is likely not the problem. just weird that most of the time it has been near by but this is why i ask. i would have been surprised really since they are nothing new, just new to me.

but to answer your questions...the chain drops onto the crank when going from middle to large chain ring. yes, i did shorten the chain, removed about 3-4 links. measured out on a table against what was taken off and compared link for link in order to keep the link count the same.

i'll just spend more time adjusting. i'm on the big ring a lot so this gives me great incentive to get it right.

Iride01 

Are you also coasting prior to shifting? I actually had a problem on my Raleigh going from the small front to the big ring. It wasn't all the time, but I noticed that it did happen after a period of coasting then beginning to pedal so I could shift gears in the front.

It turned out the freewheel was not freewheeling as good as it should and the chain had a lot of slack just made the chain flop around. It even would cause the chain to come off if I was already in the big front and coasted then hit a bump about the same time I started back pedaling.

High limit might be out of adjustment. But I seldom have to mess with limit screws once set.

Canker

chain catcher

Miele Man

Sounds like either an improperly adjusted high limit bolt, a bent chainring or a bent tooth.

Cheers

spelger

Just an update in case anyone comes looking for a similar problem, it was all me.i had adjusted the inside of the FD cage close to the chain when on the large chain ring instead of the outside of the cage. all is good in the bik-iverse again.

MudPie

Good deal!

A good sense of accomplishment to think about, diagnose and solve the problem.

MudPie

I have a chain catcher, but mine only prevents the chain from dropping off the small chain ring towards the frame. Do they make them for the chain dropping from the big chain ring towards the crank arm?

tomtomtom123

No, but you could 3d print something if you wanted to, but the reason why the chain drops to the outside during shifting is usually due to the high limit screw too far out and allowing the FD to move too far to the outside. You should only have a maximum of 0.5-1mm of gap between the chain and the outer cage plate when on the big small combination. When the gap is too big, the chain may wedge into the gap just by the momentum of shifting or the inner cage plate pushing the chain over.
You could also use a bash guard to keep the chain from falling to the outside but only if you use very thin spacers. I have to space my bash guard wider than the width of the chain to prevent chain rub because I have very short chainstay which makes sharp chain angles.

spelger

quick google search showed me this...

https://wickwerks.com/products/senti...chain-catcher/

there are others too.

Iride01 

When your chain comes off on the right side of the big ring, all you have to do is keep pedaling lightly and shift the rear DR to one of your lower gears. There is, or usually is a post between the crank arm and ring that not only keeps the chain from getting wedged between the crank, but also holds up the chain so it can re-engage the cogs at a certain point in the rotation.

I've done this a fair amount of times over the years and it usually works except for times when you are having to put a lot of power into the pedals due to terrain and such.

On bikes with friction shifters, I might even move the front DR slightly left, but with indexed shifting, I wouldn't try that.

I'm not a fan of gizmos that are added as remedies.

MudPie

Thanks, I don't have issues with chain falling off the big ring, I just never seen a chain catcher to prevent a chain from dropping from the big chainring.

MudPie

Thanks, I don't have issues with chain falling off the big ring, I just never seen a chain catcher to prevent a chain from dropping from the big chainring, until I looked at the above site.