Chain suck remedies

[roubaixtuesday]

We run Sora 9 speed 46/36/24 11-36 on the tandem.

After changing the chain earlier this year, we suddenly started to get chain suck on the small chainring, which I don't believe has appreciable wear.

This was eventually solved mid ride by applying excessive lube to the chain (yes, I was surprised this worked too), and we've since done over 1000 miles without a problem.

Then suddenly yesterday it started again.

Any advice?

It's very difficult to diagnose as can't be replicated without load.

Am inclined to buy new chainring and chain, but if so which ones?

[hoogerbooger]

FWIW: we had a year or so of chain suck problems changing from the small ring to the big ring on a SRAM Apex 10 speed setup. The chain jammed between rings and rapped around chainset if you carried on peddaling.

Spent lots of time looking for burs on the rings and did file off some suspects.....to no effect.

We seem to be on top of it now...and the culprit seems to be that the outer plates of the chain need to be very clean. Bike gets riden near the sea a lot and picks up sand. So now the outer plates get run through a rag with WD 40 regularly ( which should leave the real lube at the chain pivots)

(I suspect the issue we had/have is more likely when the chain is angled across from small ring front to smaller sprockets..... and more likely with higher number of sprockets)
(Also suspect more likely on double 50/34 than your triple)

[cycleruk]

We run Sora 9 speed 46/36/24 11-36 on the tandem.

After changing the chain earlier this year, we suddenly started to get chain suck on the small chainring, which I don't believe has appreciable wear.

Any advice?

Am inclined to buy new chainring and chain, but if so which ones?

Many years ago started getting chainsuck on the small ring, Changed the chainring, problem solved.
I don't suppose you can turn the ring round and try that.

[Brucey]

two causes of chainsuck are;
1] hooking
2] pressure burrs

the latter are caused by high force, so are more likely on smaller/softer chainrings, in fact both are; you can sometimes tell the difference because 1] is worse with load and 2] typically causes chainsuck that is more load independent.
I think it is fair to say that I have never seen a case of chainsuck that couldn't be addressed with a file.

[Jdsk]

The most problematic case that I ever had was also on a non-shifting chainwheel on a tandem. I checked the teeth over and over again and couldn't work out what was happening. Then I looked from above... the edges of several teeth were splayed laterally.

Jonathan

PS: Of course that was before I discovered this forum!

[roubaixtuesday]

It's a steel inner ring, definitely not hooked. I think it was one of these.

https://www.spacycles.co.uk/m8b0s149p24 ... eel-24-32T

Definitely load dependent, no issue on the stand.

I'll take it off and examine it closely, will post some pics.

Turning it around sounds like a good idea.

Not caused by dirty chain - the chain was brand new when it started originally. What I don't understand at all is how fitting a new chain would cause this.

[peetee]

It's a steel inner ring, definitely not hooked. I think it was one of these.

https://www.spacycles.co.uk/m8b0s149p24 ... eel-24-32T

Definitely load dependent, no issue on the stand.

I'll take it off and examine it closely, will post some pics.

Turning it around sounds like a good idea.

Not caused by dirty chain - the chain was brand new when it started originally. What I don't understand at all is how fitting a new chain would cause this.

Excessive chainline can play a part. Lateral flexibility varies from brand-to-brand and more so when comparing a fresh chain to a worn one.
Does it happen on the smaller cassette cogs or are you mindful of extreme cassette/chainring combinations?

[rareposter]

What I don't understand at all is how fitting a new chain would cause this.

New chain, old chainring is a classic for chainsuck.
Even if the chainring doesn't look appreciably worn, it will, over time, have meshed with the old chain and now that there's a new one on there, something somewhere is very fractionally not meshing correctly. Hooked teeth, a slight burr or bend on the ring...

That's all it needs to catch the chain and drag it around the chainring.

I'd just go with replacing the ring - you can spend hours chasing around it with a file or emery paper or turning it round and re-fitting but a new one is the easiest answer. When you have the chainset off to fit the new inner ring, give everything a really good scrub up too.

[hoogerbooger]

What I don't understand at all is how fitting a new chain would cause this.

I guess a new chain has less lateral flex and perhaps more likely to snag on a bur on the side of the ring? ......should there be any

( on my sandy chain example I think shaping on the inside of the large chainring may have been part of the issue, acting like burs)

[Brucey]

It's a steel inner ring, definitely not hooked.....

I would say that the fact you have chainsuck of the sort you describe is pretty damning evidence that you do have slight hooking.

[rjb]

2 options. Turn the chainring around so you use the unworn side of the tooth or use a file to smooth off the hooks or burrs. You don't need to remove much material. Try a couple of light strokes per tooth and see how it goes.

[hoogerbooger]

The burrs I did remove were found by touch/a finger nail.....but were not seen by eye before ( although it made no difference in my case...)

[roubaixtuesday]

What I don't understand at all is how fitting a new chain would cause this.

New chain, old chainring is a classic for chainsuck.
Even if the chainring doesn't look appreciably worn, it will, over time, have meshed with the old chain and now that there's a new one on there, something somewhere is very fractionally not meshing correctly. Hooked teeth, a slight burr or bend on the ring...

That's all it needs to catch the chain and drag it around the chainring.

I'd just go with replacing the ring - you can spend hours chasing around it with a file or emery paper or turning it round and re-fitting but a new one is the easiest answer. When you have the chainset off to fit the new inner ring, give everything a really good scrub up too.

Yeah, I'd got to that point. But just about to remove the old one and take a close look.

Recommendations for best 9 speed chairing and chain combos welcome.

[roubaixtuesday]

Took the chainring off, no sign of wear or burrs that I can see, pic attached.

I've swapped the chainring over, now just need some daylight to test it out.

I need this to work perfectly for a long tour next year, so I'm inclined just to replace all the chainrings and chain and start again from scratch.

Will see how it goes.

[rjb]

Plenty of wear marks there.
Tuning it around head to tail should help.