As the title says, I'm just getting back into xc/trail riding and my Dialled Alpine has 1 x 9 gearing. My old set up was 32 x 32, but that isn't possible with my LG1 chainguide. So will 34 x 34 get me up hills the same as my old set up?

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yep its the same thing… 1:1

That's great, cheers. Just goes to show how little I know about gears!

you probably have a life instead!!

I think it is the same looking at the gear tables, both combinations give 26" of forward movement for 1 crank revolution.

http://www.machinehead-software.co.uk/gear_inch_ratio_table26.html

It's identical…. No need to look at a gear table!! 🙂

both combinations give 26" of forward movement for 1 crank revolution.

No they don't. You need to multiply by pi to get the forward motion.

The gear inches given in gear tables are the equivalent height of a penny farthing wheel, which would have had the cranks attached direct to the wheel. Simples 🙂

Technically, 34:34 is more efficient than 32:32 but then as stated above, having a life is more important than knowing these 'interesting' facts 😉

34:34 is heavier, the chain goes faster with less tension

BUt the gearing is the same

34:34 is theoretically harder to get up to speed, but easier to maintain a higher speed with lower cadence.

34:34 is theoretically harder to get up to speed, but easier to maintain a higher speed with lower cadence

whaaaatttttttttt?

whaaaatttttttttt?

More of the mass is away from the centre of rotation, but it's a miniscule amount.

I'd guessed he might have meant soemthing like that about momentum making it harder to accelerate (wow, it must add 10g to the whole system!), but whats the caddence comment about?

Doesn't 1×9 mean 1 chainring and 9 sprockets?

Doesn't 1×9 mean 1 chainring and 9 sprockets?

Yes

I'd guessed he might have meant soemthing like that about momentum making it harder to accelerate (wow, it must add 10g to the whole system!), but whats the caddence comment about?

Presumably, the rotating mass means it's easier to keep the pedals spinning roung. Intertia -> momentum.

Real world: it won't make any difference.

higher speed lower cadence

no way

I'd have said that the miniscule difference a larger rotating mass would give you would be countered by the minscule extra weight of the largers cog, rings and chain….

My only thing I'd be bothered about would benefitting from the extra groud clearance of a smaller set up

Oh, I see what he means now. To acheieve the same speed, you don't have to pedal as fast.

Of course, this doesn't apply to the 34:34 or 32:32 question.

My only thing I'd be bothered about would benefitting from the extra groud clearance of a smaller set up

Two teeth is going to make naff all difference to the clearance. The circumference of the chainring will be 1" bigger, so the diameter will be 1/pi inches bigger. Half that, and you get the reduction in clearance – 4mm difference.

Wow, what an interesting thread. 😯

Wow, what an interesting thread.

Without geeks thinking about stuff like this you'd be walking, not riding.

😉