I have had three oval chainrings by two different brands break in the past year. There were plausible reasons for the first two breaks (though these were probably not the actual issue), but after the third everyone is totally stumped.
Things we have eliminated include 1) strikes — no rock strikes on the past 2 chainrings 2) chain tension — too high chain tension can break an oval chainring but this definitely isn’t the issue. 3) rear triangle flex — after thinking chain tension was the issue on the second break I over compensated.
All the chainrings have been oval. I’m running them on a 2019 Stooge Mk4, which has an eccentric bottom bracket. Rear cogs are problem solvers and the chain line has always been straight. I’m running 160mm Canfield cranks. I have had a 9 speed chain and a KMC e101 1/8 chain.
This video shows a setup identical to the most recent break, albeit with higher chain tension. https://drive.google.com/file/d/1SF-wny99molDUMPLUwi1OGHGydZE2k91
My next plan is to move to a 0mm offsetting (from a 3mm offset) but solving the problem would be best.
Thank you!
by Ok_Singer1284
27 Comments
Stop using oval chainrings made of chocolate?
Wild one!
How much do you weigh? If you’re riding a Stooge, I assume you’ve been riding bikes a while? This is a single speed, correct?
Are you buying them from amazon?
Skip leg day for Christ’s sake
Get a steel one, aluminum ones are lighter weight and way more expensive. The difference in weight is barely noticeable. Unless you’re trying to race in the tour de France, you likely don’t need a 16 lbs bike or the lightest possible stuff.
Who is selling you these chian rings and what is the manufacturer?
The Watts
Temu
Is that an Alugear chainring? They are the absolute worst from my experience. Like others have said get one made of steel and maybe a bash guard in case you break them by slamming into stuff.
You don’t have a chain tensioner. How do you manage the varying chain tension from the oval chain ring with no derailleur or tensioner?
Def not the only person to kill an absolute black ring, note that on the webs… Running the burly chromag sequence rings with no problems
I’m certainly not an engineer or anything. Looking at that I think you must be pedaling up hill from a standstill and putting all your weight on that one flatter side and doing this a lot. Could be completely way off. If you must try another oval try and find one that’s solid, if those were aluminum try steel, I think will be your best bet. That’s just what I would do. Good luck!
This is one of the possible outcomes when trying to use an oval ring on a single speed. It’s physically impossible to get uniform chain tension with that setup and that is what’s causing failures. If you absolutely need to run an oval ring and SS, you’re going to need some sort of spring loaded chain tensioner to account for chain growth.
Whats your weight?
I suspect you don’t reduce the force you pedal with when you shift gears.
Brother, you’re running an oval chainring on single speed, that’s what’s happening.
I presume that the chain is just getting way too tight. Either run a round ring, or a tensioner with a spring.
Edit before I get slammed: I’ve since done some research, and it looks like folks have done it successfully. You want to set the chain tension when it’s at the vertical, but I still think switching to a round ring would probably solve this problem.
Did you get these chainrings on Temu perchance?
Those absolute black chainrings are not very durable in my experience. In general I think alloy chainrings are kind of silly.
Try wolf tooth
Jeezum crow! I’ve bent a couple but never shattered one like that lol
What mount pattern is the crank?
Stop wasting money and just run a round Sram 11sp steel x-sync chainring.
Lay off the wattage bazookas.
Single speed with an AbsoluteCrap chainring? Are you surprised?
A couple of people have touched on it, but presumably the problem is the oval chainring on a single speed. Round rings are better for single speed because the tension on the chain stays uniform all the way around. If you can’t live without the oval ring, you’d need a chain tensioner on the back that is spring loaded to account for the variability in the oval chainring.
Also I don’t recommend anything from absolute black. I’ve seen too many things from them just absolutely fail and fall apart.
Is your chain stretched?
Why are you running an oval ring in the first place? Lol