Oval chainrings

Hard to buy that theory on the ovality IMO, not to say it isn't real however.

The readings I've done on MTB oval rings in general seem to imply that climbing is the equivalent of 1-2t easier than actual tooth count, while harder gearing is equivalent of 1-2t larger than actual tooth count. 

While fs bikes are optimized around a specific chainring size, I've yet to find consistent reports that a bike works amazingly with a 34t ring but turns into an absolute dog by moving to a 30t ring.

Maybe I'm over simplifying this though. I can't say I notice any positive or negative real effects of oval rings both on my hardtail and my fs bike.

Yes, both are 30t OneUp rings; one oval, the other round. How do you figure it would be be negligible? The chain angle is varied during the pedal stroke, directly impacting the anti-squat characteristics. I might agree that it's not drastic, but insignificant or "negligible" does not agree with with performance changes I saw between the two chainrings.

Posted by: jan

Yes, both are 30t OneUp rings; one oval, the other round. How do you figure it would be be negligible? The chain angle is varied during the pedal stroke, directly impacting the anti-squat characteristics. I might agree that it's not drastic, but insignificant or "negligible" does not agree with with performance changes I saw between the two chainrings.

The chain angle variation would also be very small and unlikely to be the night and day feeling you felt between the two rings.  Do you ride clipped or unclipped?  My thinking is that oval rings might feel quite different to someone who rides clipless to someone who rides flats.  When I switched from round to oval (I ride flats), I noticed very little difference in suspension feel.

I needed to drop a couple of teeth so i figured why not get an absolute black but since its not exactly the same size I  really can't say for sure if its better, the ovalness wasnt really  noticable compared to the bio pace of old which definatley was

I went from a 30T RaceFace to a 32T Absolute Black.  

Gear ratio wise it feels basically identical.

It didn't feel weird at all, but I don't do any road or even much fire road spinning which is where I'd expect one would notice it feeling odd.

I did have amazing traction and cleaned multiple super tech and steep climbs that generally vex me, and two that I've never cleaned before.  It's hard to know if the chainring made the traction difference however as I made changes to my suspension settings that improved climbing traction right before the same ride where I put the oval ring on.  My sense is that the ring helped in that I may have needed to watch my pedal pressure and smoothness a little less on tricky uphill moves - it kinda felt like it was smoothing my pedal stroke out for me.

The oval ring was expensive but all the shop had at the time so they gave me a nice price to convince me to try it.  My brain is still stuck on the "dollar a tooth" price guide from the old days so you can take that with a grain of salt...

Anyone know of a vendor who makes an oval ring w/more offset than normal?

OneUp makes their new 'Switch' rings in 3 offsets.  Regular, Boost and Super Boost.  This is assuming you have some sort of direct mount cranks and not 4-bolt.

RF Cinch so....maybe there is hope for my drive-line.

Ok, so I found those and thanks for the heads up that may work well for my issue.

But, just overall concept of those things is kinda' a head scratcher. Kinda' like an answer looking for a question.

I think it just makes it easier for them to produce chainrings that will fit any system. They can produce all the different spiders for cheaper id imagine, but all the chainrings are exactly the same regardless of what spider you have. In theory it makes it cheaper/easier to replace a ring when you need to. No need to take the cranks off, heck, you could even do it mid ride if you had to/wanted to.

PS They have a 20% off sale going on right now if you wanted to try them out.  I got in on the 50% limited quantity offer and am going to try one out on my next build (RF Cinch, 28T Oval, Regular).