Best Chainring Size for XC Racing

In my experience, if you’re only on single track modern 1X drive trains allow enough range. The other obvious advantage is a lighter and simpler bike set up and typically much better chain retention. After dropping my chain a bunch back in the days of 10 speed, I finally went to a 1x system and haven’t looked back. That said, if I was doing riding like you I’d have no issue using a FD.

Well I didn’t measure anything specifically but my chain started skipping (SRAM GX ) after 2 years of riding and racing. Cassette and chainring maybe half worn.

I havent experienced anything untoward. It’s kind of up to you and where you ride / race and how your biomechanicals work, but I run a 36 - so 36/34 - on my Spark with 50-10 out back.

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I’d recommend a 34 for you at Cape Epic. Lots of “fire roads”. You can use the 52 for a bailout gear on the longer climbs.

I have run a 30t and a 32t on my Spark (currently on a 30t with 10-51 XTR) and have thought about going back up for some of the flatter/road training on my MTB. I feel like the 30t up front keeps me out of the bail out gears on the cassette a good bit of the time which I appreciate, at the cost of some top end speed.

For those that consider swapping chainrings around - Do you find that your derailleur is able to accommodate changes without changing your chain or do you swap the chain length each time? If you were able to easily swap chainrings and not screw with the chain every time, I could see that as a good option.

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What gearing did you run at Shenandoah and how did you feel about it?

Does anyone know what chainring Sofia runs?

My chain is well set up for the 32T I had on, going down to 30T is perfectly within the XT clutched derailleur capabilities. Depending on how tight you have your chain set up with the 32, there’s a chance you wouldn’t even be able to shorten the chain.

I’m having the same experience as you. I’ve gone to 30T and definitely have short legs on the flats and it’s nice to be lower down the cassette on the climbs. I don’t know yet if I’m missing out but for my XCM racing it seems like the right choice.

I was going to bring both and use the 34 for prologue and most stages, but keep the 32 for (I think) two stages with really steep and sustained climbs.

I should check again but I think there is one with just up and down.

I’ve never seen these watt/kg suggestions, but they line up with my experience. I’m about 3.3 watts/kg. On my XC bike, I’ll run a 32 if the race is long and/or particularly steep, 34 otherwise. 10-50 rear cassette.

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I got “gear shamed” once at my local shop. I brought my trail bike in because I couldn’t figure why my drivetrain was skipping. The mechanic asked me if I spent a lot of time in my 50 in the rear. I had to admit that I did. He said I wore it out, and suggested I go down to a smaller front chainring. I think I was only on a 32, so that was a little embarrassing.

I’ve just ordered an Oval 32T chainring to try out. It’ll be interesting to see if the benefits are as claimed/reviewed. It’d be nice to have the gear ratios of a 32 still but be able to have a gear lower in the rear.

Don’t be embarrassed, it happens to lots of guys. :stuck_out_tongue_winking_eye:

Offer to sell him your cassette as “like new” since you only used one gear :wink: Maybe that would shut him up.

Honestly don’t be embarrassed but going to a 30 would help a bit. Alternatively just keep rocking what you are riding. Wearing out components to me always feels like a bit of an accomplishment.

I currently run a 34 with an 11-50 in the back. Even though I have quite a low ftp, I don’t seem to have trouble climbing even the steep ski resort trails in park city Utah. Even on recovery day. I would be interested in a 36 if Shimano ever makes a cog bigger than the 51t. The gear jump on the new eagle 10-52 it just awful

I am 3.8-4.1 W/kg and I ride 30T x 10-51T. I need the easy gears quite a bit - I ride in the Kootenays a lot. So I think the ranges shift depending on the terrain.

Nah, don’t be ashamed! I just went 52-32. Gears are nice!

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I’ve always believed an oval is 2T up on a round chainring. i.e. a 32T oval is the same as a 34T round as the power quadrants are equivalent to a 34 and the transition quadrants are equivalent to 30T. (Give or take).

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Start using a 34 in training now. What’s the worst thing that can happen from having to push your legs harder in training…you’ll get stronger legs (with proper nutrition and recovery of course).

I ran a 28 tooth front on a 10-42 11 speed when I lived in Southwest VA and sometimes I wish I had another gear haha

Nothing wrong with going to smaller gear if that’s what you need. If anything it’s the smart thing to do. By going too big you’re only making things harder on yourself.

It’s like spending beyond your budget. It might look cool to others to have some cool, new, expensive things but you’re only hurting yourself in the end.

I’m considering an overall, I’d be grateful if you could post up your opinions when you’ve had a few rides. (there seems to be 50/50 a split on whether they work or not)

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