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Oval chainwheel


twotommos's picture

By twotommos - Posted on 29 February 2016

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MrMez's picture

Yep. That specific one.

There has been loads written on these, the bottom line, it helps some riders and hurts others.
You can't tell until you scientifically test both, which is why some pros use them, and others don't.

I found it handy for MTB on slow rough sections where speed can drop suddenly.
As I have a very efficient, fast pedalling style already, it actually hurt my cadence everywhere else.
It also teaches you bad habits like low cadence. It can make you faster today, but slower in the long run.

I took mine off after ~6 months use.
It also knackered the clutch on my RD as the chain length DOES vary with every pedal stroke.

ptpete's picture

I converted to a rotor brand oval chain ring 2 years ago, which I ran on a single speed. I only noticed the difference when going back to a standard ring. the difference really shines through on steep climbs, and if you are prone to cramping due to excessive efforts (not hydration linked) than it helps a lot too.
I recently converted my bike back to gears and put a wolf tooth oval chain ring on, and love it.. I tend to be a power climber rather than a cadence climber, so it suits my style well. As for the clutch derailleur issue, I think you might find that the clutch failed for other reasons, as the chain length "barely changes" through the pedal stroke and am happy to video it to show. I ran my single speed without a tensioner for a while and had no issues with loose/tight chain. (mtMez, don't take personally, on based on my experience)
As noted though, they may not be for everyone. Put one on, do your favorite ride a few times, then put the standard one back on and see what you think.
this way you can decide for yourself.

Pete

MrMez's picture

I should point out that I use a Saint RD, which is primarily designed for a close ratio 11-28.
The cage is super short, which I believe makes it worse? Pulling the same distance over a longer lever = less degrees of rotation. Plus the clutch is ultra firm.
Although it doesn't pull much it's clearly visible, and averaging ~80rpm for ~3 hours/week = over 14,000x2 cycles (it's oval, not eccentric, so 2x full cycles per revolution). That's close to a million times the RD has been pulled and released in 6 months.
Probably much less an issue with an RD with a longer cage and less restrictive clutch.

ptpete's picture

That's a lot of spins... I run a Zee rear mech as I find it more effective for chain tension on a 1x setup.. plus its bullet proof.
I will have to calculate my monthly leg rotations just to see the number.

Pete

twotommos's picture

I was thinking of trying this on my single speed which currently runs a 32 up front....I run a chain tensioner, so that should be right too....I do like to spin but that isn't always possible on a SS as you might appreciate.

Pants's picture

I've been running that exact ring in the photo ever since they released it on their website so ~1.5 years?

It really helps getting up over tech stuff as you dont get hung up between pedal strokes when the power normally drops. You find that your pedals 'accelerate' between strokes to get you where you put down the maximum power.

It does take a little bit to get used to, but I find no problems swapping between my roadie and then back to it.

If you normally have a high cadence then it will feel very awkward for you to ride this thing.

I am not going back to normal ring on the mtb!

hawkeye's picture

You have a roadie?

But... but... but... Shocked

stephen's picture

I use an Absolute Black on the single speed, makes climbing smoother so aids traction and takes a bit of the coppiness out when doing stupid high cadence. My ride has horizontal dropouts, the chai length varies bugger all so no problem with chain tension.

twotommos's picture

Good to know having seen your ride

twotommos's picture

Stephen what size are you riding at the moment?

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