NW Chainrings- Filing for extra life

LPG

Likes Dirt
So I've been getting my bike ready for a trip and when I changed the chain I found that it's running rough on the chainring when under load. The bike was built with new drive train in June with ~30-50km per week with 800-1800m of climbing. The chainring shouldn't be worn.

I suspect the square nature of NW teeth means that any wear means that the square teeth foul on the chain rollers as they enter and exit the chainring. Instead of reinstalling the old chain I'm thinking of filing a little chamfer on these square tooth tips. I'm running an oval chain ring and I suspect it's the area of the tight radius on the chainring that is causing the issue. Hopefully that is clearly described, I CBFed drawing a diagram.

Anyone ever try this? I shouldn't cause any issues if I stay close to the tip but if I cause issues I'll have to scramble for a replacement chainring before the end of the week.
 

Oddjob

Wheel size expert
What brand chainring?

You might as well get the spare and then experiment to your hearts content.

Sent from my SM-G970F using Tapatalk
 

creaky

The obviative
What wear / stretch did you measure the chain at before changing?
With all the use on a single chainring, they do wear out quickly. Cassettes last heaps longer than chainrings now.
 
I had the same on an Absolute Black oval ring, possibly slightly more than 0.75 chain stretch when I replaced the chain after around 1,500km of use. Replacing the ring fixed the issue, I didn't consider filing down the teeth.
 

sebbyreddan

Likes Dirt
I had a similar issue with an Absolute black oval ring, new chain was noisy as, under power. It quietened down after a few rides.
 
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LPG

Likes Dirt
Thanks everyone. I don't have a wear gauge but I have many years of pulling chains off and hanging them next to the new one. This one looked pretty good. There would only be 500-900km on it and a lot of the climbing for the local trails are steady climbs up paved roads.

I'll give the tips a tickle and report back.

I had a similar issue with an Absolute black oval ring, new chain was noisy as, under power. It quietened down after a few rides.
Good to hear, that's what I was thinking and thought a touch off the tips would help it along.
 

LPG

Likes Dirt
So I gave it a quick filing last night. I didn't take much off. It seemed like it might be a bit better but the noise is still there under load. I'm going to try and ride it in from here. I dont want to go too far with the filing.

Looking closely at the chainring it did seem to be a bit more worn than I would have expected for the life. I'm thinking I may go to a round chainring next so I can rotate the ring. I'd love to have a steel oval ring but it doesn't seem to exist from what I can see
 

Zaf

Gearbox Frother
It's annoying that we traditional chainring options aren't readily available anymore, especially after the explosion on ISCG mounts and using chain retention devices. It seems like it's one of those things that have killed backward compatability with chains, because the older Narrow/Wide chainrings for a 10sp and 11sp systems won't be compatible with 12sp chains due to the tooth width.

If you're chasing Steel Oval rings, the WolfTooth CAMO rings are your only option that I'm aware of, so will need to buy the 5bolt direct mount spider for them first, which jacks the price a little.
 

LPG

Likes Dirt
A bit of an update. The filing seemed to help a little bit (maybe). I decided not to file too far so just rode it in. This happened quickly as it was on a riding/camping trip to bright and there was rain and mud making things grind into shape nice and quick;y. I won't bother filing in the future, riding seems to do the trick.
 
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