how much dropout play do i need?
08-17-06, 04:48 PM
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how much dropout play do i need?
I have a super old cannondale i want to turn into a single speed. i'm wondering how much dropout play i need to keep an average amount of chain slack.
08-17-06, 04:50 PM
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I'm not 100% sure what you mean by "an average amount of chain slack", but I believe you need 1/2" of adjustment in the dropouts. If it's a single speed and not a fixed gear you can get a chain tensioner or set an old derailleur if you have vertical dropouts.
08-18-06, 06:12 AM
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If you're willing to use a half-link, you only need 1/4" of play.
08-18-06, 07:52 AM
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as much play as you can get. any extra ladies, send em over here.
08-18-06, 08:28 AM
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dammit I was gonna make a gettin play joke
08-18-06, 10:03 AM
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Depends on how many choices you want for gearing. If you can find a gear ratio that you like which lands your rear axle safely within the dropouts and leaves about an 1/8 inch gap behind the axle with a new chain, then you only need 1/8 inch of play. You need the 1/8 inch gap for chain stretch. Makes it easy to know when you need a new chain.
I have a SS rigid MTB conversion that is like this. I run 35x16. A new chain puts the rear axle just inside the dropouts. When the chain stretches enough that I can't get enough tension because the axle is against the back of the dropouts, I buy a new chain. I'm happy with the 35x16 ratio. If I want to change the gearing, I have to do it in increments of 4 teeth (or 2 teeth with a half link).
I have a SS rigid MTB conversion that is like this. I run 35x16. A new chain puts the rear axle just inside the dropouts. When the chain stretches enough that I can't get enough tension because the axle is against the back of the dropouts, I buy a new chain. I'm happy with the 35x16 ratio. If I want to change the gearing, I have to do it in increments of 4 teeth (or 2 teeth with a half link).
08-18-06, 08:20 PM
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Originally Posted by SamHouston
dammit I was gonna make a gettin play joke
08-18-06, 09:14 PM
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I was told that as long as you are not flush with the back of the dropout, or partly off the dropouts...that is enought room (don't mess with your wheel falling off). Use logic, you will know after riding it if you have too much slack and you can see if you don't have enough...how reduce slack is an easier question to answer than asking how much to allow...especially on DIYSers 
