Ovals..

In my last post, I said how I was wanting to try oval chain rings. Well, due to good fortune, I’ve come by some.

So, I stripped down the chainrings, threw out the knackered shimano bolts, and installed the new rings, with a helping of anti seize paste on both parts of the bolt. Just watch out for this stuff, a tiny spot on the fingers, and your finding spots of it all over for months. It’s really tenacious stuff.

Fitting them onto the bike, it’s noticeable just how odd they appear. They where easy to install however. I hadn’t changed the gearing, sticking with the same 50/34 the bikes always had. Installation meant I had to move the front derailleur up, to account for the greater height of the large ring. The official installations have instructions to fanny about with the limit screws. I didn’t have to touch those. I raised the derailleur, ensured the cage was parallel with the ring and then set the cable tension, ensuring the gaps were correct.

Testing the shifting, it was absolutely fine, didn’t drop or over shift, and each change happened as expected.

The first few rides, I never really felt any difference in the pedals, but a few rides, I started to notice a couple of things. Firstly, I was riding higher in the cassette (smaller cogs) because my cadence had shot up, to get my favoured RPM, I’d had to start using gears well up the cassette. This meant that I’ve also started to use the larger chainring a lot more than I ever have.

“Our Oval chainrings work because a rider does not produce power evenly through a pedal stroke; they maximize the part of the stroke where power is produced and minimize resistance where it isn’t. Oval rings make the spin cycle a lot smoother and are easier on legs while climbing. Believe it (or not), but a round chainring doesn’t transfer torque to your rear wheel as smoothly as an Oval one. You will actually feel your stroke to be more “round” with an Oval shape than with a round chainring.”

absoluteBLACK

Secondly, I was rotating the cranks easier, and for longer. I found it a lot easier to just keep going. Coasting was down and out. This may be down to the fact it feels smoother, less forced as that “Dead Zone” is overcome with the oval.

You can see in the graph above, cadence is constant, speed and power are levelling out. It just seems easier to keep going. When sprinting, the power just seems more urgent, and direct.

Don’t get me wrong, these chainrings are not going to change you into Bradley Wiggins overnight, but they do, clearly make a difference, to me at least. I’d recommend, if you need to change worn chainrings, give them a try and see if they are for you. One of the drawbacks, I’ve noticed a few people looking, and noticing this weird wobbling thing. 😏