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trialsiain

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i opted for 170's after riding previously with 175's, noticable difference straight away, could gap further immediately. recently changed my gear ratio to 16:13 from 16:14 and again i feel like i am getting a benefit out of it. i think before i was at the ratios' limit for me, but now it is harder to pedal, but can gap further again. the only reason for a light ratio is for natural with short run ups, but i havent found this to be a problem as of yet.

cheers, ash

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Do long cranks still work if your a short arse ?

Crank length comes from the length of your legs. As in on road bikes the lager size frames will have longer cranks and long stem, longer reach etc.

I think if you have shorter legs then the ill affects of longer cranks might be worse. But not sure

Personally I have tried longer and shorter so I could feel the difference. If you can try some out?

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the only reason for a light ratio is for natural with short run ups

Kind of... But I used to have a 24 with 24:14 and at that stage it's very detrimental to anything other than going fast when you've lots of space.

You may have had it too light for your body/how you ride, but if you go too far the other way it'll impede your riding just as much (or potentially more if you get silly with it. Haha).

(Obviously when we say a "light" gearing, we're actually discussing a gearing being even lighter than the already insanely light average trials gearing, so you'll have a little wiggle room yet I reckon ;) )

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I remember a time when James porter was running 18:17 when everyone else was running 18:15 but it didn't affect him so I was reluctant to go heavier seeing what he could do.

But now I'll only be going to change when I swap my front cog as it's a 16. And chains tend to snap with smaller cogs so im wary of that. Then I will have the decision of 18:14 as that is next ratio to trial

Cheers ash

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The only thing that alters gear ratio is by physically changing a sprocket or freewheel. All long or short cranks do is increase or decrease the amount of effort needed to make the bike move along at that given ratio. You want heavier gearing, get a smaller rear or a bigger front sprocket, or vice versa for lighter gearing. Basic physics dictate if you have a longer lever, less effort is needed to perform the task

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Hilarious I know :giggle:

Edit: It's just I always thought the gear ratio and wheel size were the only things to affect distance travelled per crank revolution.

Shorter cranks give your a small circumference so on a short run up- half pedal stroke you can start closer

So your foot actually has to travel less for the same distance the bike moves.

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One 360 degree crank rotation still gives 18/15ths of a rotation of the rear wheel though, so the bike travels the same distance... Your foot travels less, yes, but you can't start closer to the obstacle because the bike travels the same amount of horizontal distance.

By your foot travelling less distance it also confirms that shorter cranks give less leverage: work done = force * distance, so if you apply the same force over less distance you have done less work and therefore the bike hasn't accelerated as much.

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One 360 degree crank rotation still gives 18/15ths of a rotation of the rear wheel though, so the bike travels the same distance... Your foot travels less, yes, but you can't start closer to the obstacle because the bike travels the same amount of horizontal distance.

By your foot travelling less distance it also confirms that shorter cranks give less leverage: work done = force * distance, so if you apply the same force over less distance you have done less work and therefore the bike hasn't accelerated as much.

So please tell me why all the top riders in the whole wide world use shorter cranks rathan longer ?

I'm just trying to help you guys out. But if you want to listen to these guys who arnt really the best riders in the world fair enough. No offense by the way Adam.

I give up

I also want to make it clear that I'm not claiming to be any good. I'm referring to such risers as Gilles coustellier Vincent hermance kenny bealey and jack Carthy. Jack runs 165 on stock too

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So please tell me why all the top riders in the whole wide world use shorter cranks rathan longer ?

pedal clearance and weight weenie-ism.

also i'd imagine personal preference plays a part.

Edited by err
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I always thought shorter cranks make the bike more responsive to lift the front up for shorter run ups, but that was just a theory haha ? cause i had long cranks on my 24 and it always felt a bit "loose" as if it would have been better with 170mms

Edited by trialsiain
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pedal clearance and weight weenie-ism.

also i'd imagine personal preference plays a part.

Same with Abel- still runs 158mm monty cranks which are old as and he's not even sponsored by monty any more. Strange trend..

Strange they all have the same personal preference

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In fairness, Abel might want to run them 'cos the Monty cranks are around 360g whereas Ozonys don't really do a light set of cranks (the Bonz cranks they stock on their bikes are well over 500g).

Is that a guess or did he tell you that him self ?

I will ask him next time I'm chatting to him if you want.

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So please tell me why all the top riders in the whole wide world use shorter cranks rathan longer ?

I'm just trying to help you guys out. But if you want to listen to these guys who arnt really the best riders in the world fair enough. No offense by the way Adam.

I give up

I also want to make it clear that I'm not claiming to be any good. I'm referring to such risers as Gilles coustellier Vincent hermance kenny bealey and jack Carthy. Jack runs 165 on stock too

I'm not sure actually. A lot of trials is really psychological it seems. One rider does something which may well be placebo and everyone copies, it's just the way it is.

No offence at all - people can do what they want, but the physics doesn't change.

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I'm not sure actually. A lot of trials is really psychological it seems. One rider does something which may well be placebo and everyone copies, it's just the way it is.

No offence at all - people can do what they want, but the physics doesn't change.

like the forward bar angle ?

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