Currently have a 30t round chainring on my enduro, soon to be going on a alpine “enduro” tour week and wouldn’t mind changing to something that will be a bit easier on my legs across 6 days of riding.

Considering either going for 2t less or an oval chainring. Recommendations please.

got 40 or 42 on the back?

Just fitted a 32 oval, very happy with it

Can you tell any difference in effort when riding? I have seen a few suggest they end days with their legs feeling less destroyed when running oval rings, but I kind of want to spin a little more going up hill and feel like I am putting in less effort at the time as well.

Whatever size round you think you need go up 2 teeth on an oval. Oval helped a lot with climbing for me but a lot depends on what you’ve got on the back like previous post asked.

You can spin an oval but you don’t get the peaks in the stroke when you get all stampy when the going gets tough. Much smoother with the oval in my experience. But I bought two so of course I’ll say that…

Had a 30T round and went to a 32T oval. Much improved pedal stroke and very good when out of the saddle. I’m running a 40t rear..

Still can’t tell any difference myself. Not to say there isn’t any, I could be using a higher gear than usual or going faster- but it’s not something I’m aware of. Too situational I suppose without real a/b testing

I’m running 1×10 (inc 42t OneUp cog) + 32t wide-narrow chain ring. A month ago, replaced round CR with 32t oval (Absolute Black, fyi) mainly to protect an increasingly fragile knee. First time I rode it, thought there was no obvious difference. Then saw times on Garmin. Amazing – more than a minute off best time for Swinley blue trail! Been getting consistently good times since then too. OK, it’s been perfect MTB weather & the trails are as good as I’ve ever seen them, but even so… On reflection I’d say because the oval ring makes pedalling a bit easier, & you’re still putting in the same effort, you just go that little bit quicker anywhere where pedalling makes a difference. You won’t gain anything on downhills of course & maybe not all that much uphill (hard hills are always going to be hard; if that’s a problem that’s what ebikes are for) but on pedally uppy-downy stuff, wow! So I’d say go for the 30t oval as you’ll gain nearly as much as a round 28t would give you, & you’ll keep your top gear (& maybe find you’re using it a bit more too). One word of warning – contrary to official advice I had to add a couple of links to my chain to get a really smooth pedalling action, tho the chain was a bit on the tight side before & I do have that oversized big cog. Enjoy the Alps – I’m jealous. Good luck & good hunting.

I have an oval ring, feels nicer but I don’t believe it’s saving any watts (and if it was it’d be proven and we’d all be riding them), so I’d go 28T.

cynic-al wrote:
I have an oval ring, feels nicer but I don’t believe it’s saving any watts (and if it was it’d be proven and we’d all be riding them)

Oval rings have been around for years. Some roadies use them, Chris Froome for example, & you’ll see them regularly on TT bikes. Those guys count every watt. It’s true, though that oval rings have never really caught on. My understanding is they don’t work too well with front derailleurs. So I’d guess it’s only the sudden groundswell of 1x drive trains that’s got the techy types thinking about them again & the small aftermarket manufacturers, like Absolute Black, have seen a niche the megacorps missed or weren’t interested in.

Ordered an oval, I will give it a go, still time to order a smaller round ring if it doesn’t impress after a few weeks.

**oval curious**

Did you go +2 or your normal t?

No went for the same, as the objective was to make life easier.

Biopace was oval and worked with a front shifter. In the 1990s ever bike had it.

Changed cycling as we know it 😉

28t round won’t fit on a 104 BCD crankset so that may make the decision for you.

Biopace was 80s…90s was round!

That’s got me thinking

Mid 80 was round

Mid 90s was round

I suppose Biopace was late 80s. The weird thing was I think biopace did the opposite of a modern oval ring

If I’ve understood it right, if one is currently using a round 30 then an oval 32 should be ok? (A general question rather than directly related to the OPs query).

Didn’t we all work out that Biopace was snake oil 30 odd years ago?

Yes we did but it was 90° to the modern version – which may as well be snake oil given the exaggerated benefits its proponents say it has.

Yeh, see here Tga
* 32T oval ring will suit best someone who uses 30 or 32T chainring currently. While pedaling, you will feel quite similar effort to the one riding round 31T ring (as the smallest diameter of the oval is 30T), but you will gain the speed similar to riding 33/34T chainring.
I thought I might be over geared with a 32t but it’s fine for me, just like the way it works. A long grassy climb that I normally spin up in quite a low gear I find it easier a couple of gears higher than normal.

Cheers dave

What have folk done re chain length? I had a 32T round chainring and shortened my chain to suit (round the chainring and big sprocket plus two links). Then I swapped to a 30T round and didn’t need to do anything to the chain. If I fitted a 32T oval would I be likely to need to alter the chain length?

The oval 32t is the same as a regular 32t chainwise

Ok cheers. I was reluctant to ask as it seems a stupid question, 32 being 32, but have a vague recollection of seeing something about it, which I probably just misread.

Right then where has 30t 104bcd?

Struggling to find one

http://forums.mtbr.com/drivetrain-shifters-derailleurs-cranks/absoluteblack-chainrings-thread-874053-9.html

The guy from AbsoluteBlack has posted loads on this mtbr thread, and he says, near the bottom of page 9, that 30T with 104bcd isn’t possible.

There is no free lunch

Whatever size round you think you need go up 2 teeth on an oval.

Not what I found at all.
Swapped a 32 round ring on a singlespeed to a 34 oval on this kind of recomendation.
Then found that I couldn’t get up one of the climbs on a local ride that i could with the 32 on.

^^ same for me 32 to 34 oval on ss, much harder work compared to the same effort I was expecting. Besides, with gears unless you’re spending a lot of time in the 11 cog at the back why would you want more teeth at the front? Coming from someone who rides out his door onto trails so accept it may be helpful to those that do road sections to get to trails.