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11-40/42 Sunrace ca...
 

[Closed] 11-40/42 Sunrace cassette on a 24" wheel - ground clearance for the mech?

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I'm trying to get a nice 'spinny' 1st gear for my daughter on her Orbea 24" bike. I've dropped to the smallest chainring I can but she still needs a bit more for longer, steeper stuff.
I'm concerned that the bottom of the rear mech might be very close to the ground when she's in such a large sprocket on a 24" wheel.

Has anyone done it, got photos/real time experience?

Cheers


 
Posted : 31/08/2017 11:20 am
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Anyone? Bueller?


 
Posted : 31/08/2017 5:14 pm
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Rear mech cage clearance wont change with a larger cassette.. its the cage length that dictates this.
right?
Plus, once you are past mid cassette, the cage is going to swing past its lowest point and up forwards as the chain effectively tensions/shortens.


 
Posted : 31/08/2017 5:39 pm
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Posted : 31/08/2017 5:43 pm
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If you're using the same mech, then the lower cage will roughly follow the same arc regardless of sprocket size. As above, maximum extension is mid-cassette, then it pulls forward and up.

22-42 is a very spinny gear though. Will she even move?


 
Posted : 31/08/2017 5:46 pm
 Chew
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Just measured mine
21 cm drop from the axle to the bottom of the mech.


 
Posted : 31/08/2017 6:39 pm
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Thanks. Might give it a go, bikediscount have them for quite cheap.


 
Posted : 31/08/2017 9:19 pm