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Technical & Reference Section => Tech and Restoration => Topic started by: BMX1973 on September 06, 2016, 12:17 PM

Title: Chainring and Freewheel Ratio
Post by: BMX1973 on September 06, 2016, 12:17 PM
I know there have been similar threads about this before.

On a 20" BMX most riders use a 44T Chainring with a 16T Freewheel.

My question; what is equivalent to this on a 24" BMX Cruiser?

I will probably be using a 40T Chainring.  :-\

Thanks in advance.  :daumenhoch:
Title: Re: Chainring and Freewheel Ratio
Post by: Jaymz on September 06, 2016, 01:00 PM
41/17 with 175mm cranks
40/17 with 180mm cranks
Title: Re: Chainring and Freewheel Ratio
Post by: BMX1973 on September 06, 2016, 03:08 PM
Cool  :coolsmiley: Is there a chart that I can down load from somewhere? Thanks. :)

Why is it a different set up to a 20"?   :-[

Could you still use a 44T & 16T or would it all be set up wrong. Seen a couple of 24" like this.  :-[

41/17 with 175mm cranks
40/17 with 180mm cranks
Title: Re: Chainring and Freewheel Ratio
Post by: Jaymz on September 06, 2016, 03:17 PM
Pretty sure theres a thread on the museum with a link to something, failing that try sheldon browns website
Title: Re: Chainring and Freewheel Ratio
Post by: rooski on September 06, 2016, 07:15 PM
2.75 is the best ratio for 20" wheels, not sure about 24" bit less I think( 2.3? )

Divide big by small eg 44/16 =2.75  40/15 =2.66 

24" wheel is a different ratio as the bigger wheel is harder to turn.

Title: Re: Chainring and Freewheel Ratio
Post by: BMX1973 on September 06, 2016, 08:57 PM

Thanks rooski.  :)

2.75 is the best ratio for 20" wheels, not sure about 24" bit less I think( 2.3? )

Divide big by small eg 44/16 =2.75  40/15 =2.66 

24" wheel is a different ratio as the bigger wheel is harder to turn.


Title: Re: Chainring and Freewheel Ratio
Post by: Hmoon27 on September 06, 2016, 10:04 PM
There is a table on here somewhere.
44t up front is a bit too big for a cruiser, unless your just pootlin' around. I raced cruiser a few years back , started high up front and ended up riding 39/17👍
Title: Re: Chainring and Freewheel Ratio
Post by: VOIVOD on September 07, 2016, 04:38 PM
http://bmxultra.com/gear-calculator/
Title: Re: Chainring and Freewheel Ratio
Post by: BMX1973 on September 07, 2016, 09:15 PM

Thanks chaps.  :)
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