Forum menu
Is 34 x 34 about th...
 

[Closed] Is 34 x 34 about the same as 32 x 32?

Posts: 0
Free Member
Topic starter
 
[#1127312]

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?


 
Posted : 14/12/2009 9:49 am
 mos
Posts: 1588
Full Member
 

?


 
Posted : 14/12/2009 9:50 am
Posts: 0
Free Member
 

yep its the same thing... 1:1


 
Posted : 14/12/2009 9:53 am
Posts: 0
Free Member
Topic starter
 

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


 
Posted : 14/12/2009 10:01 am
Posts: 0
Free Member
 

you probably have a life instead!!


 
Posted : 14/12/2009 10:04 am
Posts: 11590
Full Member
 

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


 
Posted : 14/12/2009 10:07 am
Posts: 19914
Free Member
 

It's identical.... No need to look at a gear table!! ๐Ÿ™‚


 
Posted : 14/12/2009 10:12 am
Posts: 11937
Free Member
 

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 ๐Ÿ™‚


 
Posted : 14/12/2009 10:23 am
Posts: 0
Free Member
 

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 ๐Ÿ˜‰


 
Posted : 14/12/2009 10:32 am
Posts: 9969
Full Member
 

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

BUt the gearing is the same


 
Posted : 14/12/2009 11:04 am
Posts: 0
Free Member
 

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


 
Posted : 14/12/2009 11:06 am
Posts: 41848
Free Member
 

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

whaaaatttttttttt?


 
Posted : 14/12/2009 11:11 am
Posts: 11937
Free Member
 

whaaaatttttttttt?

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


 
Posted : 14/12/2009 11:16 am
Posts: 41848
Free Member
 

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?


 
Posted : 14/12/2009 11:24 am
Posts: 1083
Full Member
 

Doesn't 1x9 mean 1 chainring and 9 sprockets?


 
Posted : 14/12/2009 11:37 am
Posts: 11937
Free Member
 

Doesn't 1x9 mean 1 chainring and 9 sprockets?

Yes


 
Posted : 14/12/2009 12:08 pm
Posts: 11937
Free Member
 

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.


 
Posted : 14/12/2009 12:10 pm
Posts: 9969
Full Member
 

higher speed lower cadence

no way


 
Posted : 14/12/2009 12:15 pm
Posts: 0
Free Member
 

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


 
Posted : 14/12/2009 12:18 pm
Posts: 11937
Free Member
 

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.


 
Posted : 14/12/2009 12:18 pm
Posts: 11937
Free Member
 

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.


 
Posted : 14/12/2009 12:22 pm
Posts: 0
Free Member
 

Wow, what an interesting thread. ๐Ÿ˜ฏ


 
Posted : 14/12/2009 12:26 pm
Posts: 11937
Free Member
 

Wow, what an interesting thread.

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

๐Ÿ˜‰


 
Posted : 14/12/2009 12:27 pm