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NZ_Rida
11-21-05, 03:57 PM
Hello.
i've got a gearing question (my dirt jump bike, Giant Rhythym) has currently got 39 x 14T gearing on it and i was thinking of changing it because its sucks!!! i need a better gearign combo for street/dirt becuase at the moment my gearing dosen't accelerate that well and I would like better acelleration for the riding i do. the current gearing makes the bike feel slow and slugish which isn't that great.
thanks,
Dan
mude
11-21-05, 03:59 PM
when you say "dirt jump bike" is that implying you have more then one bmx or more then one bike...
NZ_Rida
11-21-05, 04:01 PM
I only have one BMX
Brian
11-21-05, 04:03 PM
Gearing won't make your bike feel sluggish, you're just weak. 39x14 sounds like you're spinning too much and not going anywhere. Do you have a cassette hub?
mude
11-21-05, 04:04 PM
if you go to www.danscomp.com you can click links to find a gearing chart where you put the number for the chainwheel and for the freewheel/cog and it'll tell you what that ratios good for.
queensrider86
11-21-05, 04:13 PM
get a 25t, you will accelerate really good
Brian
11-21-05, 04:18 PM
get a 25t, you will accelerate really good

Yeah, if he's got 36" tires, that would be great.
lyledriver
11-21-05, 04:28 PM
39/14 is a pretty standard BMX ratio.
For every crank revolution, your back tires revolves 2.78x.

I'm curious as to what kind of dirt jumping you do, that requires a lower gear ratio than that.
CMcMahon
11-21-05, 04:43 PM
Probably the kind where he's not pedalling hard enough and is trying to blame it on the gearing.
queensrider86
11-21-05, 05:00 PM
just get a 25t, it accelerates way better. ask anybody
bmichaelx
11-21-05, 05:24 PM
just get a 25t, it accelerates way better. ask anybody

No dude don't get a 25T sprocket, that won't help you.

Get a 23T
racersk66
11-22-05, 01:15 PM
No dude don't get a 25T sprocket, that won't help you.

Get a 23T
HAHA.
I_Suck_At_BMX
11-23-05, 10:20 AM
you have to remember to get a bigger freewheel too.

23/18 will answer all your accelerating dreams.
racersk66
11-23-05, 10:38 AM
you have to remember to get a bigger freewheel too.

23/18 will answer all your accelerating dreams.
Yeh that should work, should be really good for dirt.
I_Suck_At_BMX
11-23-05, 10:42 AM
Yeh that should work, should be really good for dirt.


what do you mean should??, itll definatley work, we're talkin about a 1.27 ratio, theres nothing better.
racersk66
11-23-05, 11:06 AM
what do you mean should??, itll definatley work, we're talkin about a 1.27 ratio, theres nothing better.
HAHA
KinetikBiker
11-24-05, 07:02 AM
if you dont care about size...then go with something like a 41-15...but it will take strenght

but 39-14 is one of the standard ratios for bmx gearing

but the others are

44-16, 41-15, 39-14, 36-13, 33-12, 30-11, 28-10, 25-9, and if you have the new primo hub you could buy there 8t driver and a 23t chain wheel for a 23-8

but i wouldnt go any smaller then 30-11...becuase the smaller the chainwheel the more pressure and wear you get faster....