Flip flop hub max cog difference
05-14-15, 11:01 AM
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Flip flop hub max cog difference
What would be the maximum size difference in cogs that could be used for each side? i.e. if I'm using a 19t on the freewheel, what's the lowest cog size I can go on the flip side that would work with the chain/dropout?
05-14-15, 11:05 AM
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Depends on the length of your track ends.
05-14-15, 11:06 AM
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That depends on the length of your dropout and where the axle sits in the dropout currently. I usually say 2 teeth but if the axle is in the middle that will effect how much tension you can take up.
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05-14-15, 11:07 AM
#4
Calamari Marionette Ph.D
Depends on your current chain length, (where your axle sits now) and the length of your dropout slots.
*** Every tooth added or subtracted will move the axle 1/8th inch.
*** Every tooth added or subtracted will move the axle 1/8th inch.
05-14-15, 11:07 AM
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For each tooth added or subtracted the rear wheel axle moves approximately 1/8" in the dropouts, so you should be able to figure this out.
05-14-15, 11:10 AM
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05-14-15, 12:04 PM
#7
Your cog is slipping.
Your axle will move forward or back about 1/8" for each tooth added or subtracted.
05-14-15, 12:19 PM
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According to the late Sheldon, run them the same or with 1-2 teeth difference. Typically I run a 16t freewheel opposite of a 17t fixed cog. That will allow you to use the same chain and let your track ends take up the slack.
05-14-15, 02:09 PM
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I'm squeaking by running an 18t slammed and can get a 14t at the end, like others have said, it all depends on the length of your dropouts.
05-14-15, 04:11 PM
#10
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I have cross check built as fixed/fixed and I have 17 and 20 cogs.
with 38 in front - 17 is slammed all the way back and 20 is close to opening
with 38 in front - 17 is slammed all the way back and 20 is close to opening
05-14-15, 07:00 PM
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I would recommend staying within 2 teeth difference. And if you're running single speed instead of fixed, then it's not just the track end length that matters, but also your brake pad alignment.
IMHO, if you need single speed/fixed gear with more than two teeth difference then what you really need is A) a geared bike or B) another singlespeed/fixed gear bike
IMHO, if you need single speed/fixed gear with more than two teeth difference then what you really need is A) a geared bike or B) another singlespeed/fixed gear bike
05-14-15, 07:19 PM
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guy dropped the ball on that one though, he has 4 bottle openers he couldve used on that rear axle alone
05-14-15, 07:36 PM
#15
Tourer
If you use some creativity, you can have a very large difference in the number of teeth on your cogs. The solution is to have two chainrings up front with same tooth differential. Move your chain front and back and your rear wheel stays in the same place. This concept is the principle behind the Surly Dingle . You would be using your flip-flop hub in the rear instead of the Dingle. Here is video showing the system.
