Singlespeed Build---HELP!
10-04-12, 06:10 PM
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Singlespeed Build---HELP!
My fiancé bought a failed attempt of a Trek fixed gear. I want to convert it to a manual two speed for his birthday. My budget is 200 for the parts I still need. I have already purchased Shimano 600ex brake levers and cable housing. Here is where I need help.
Problem 1: I would prefer to buy two chainrings (46 and 36). The current chainrings are 130bcd. Can I buy two chainrings or do I need to buy a new crankset? If I can get away with buying two chainrings, what do I need to know to make sure they are compatible?
Problem 2: I have brake levers. I need brake calipers. What do suggest that will look good and function reliably.
Thanks for all of your help!!
Problem 1: I would prefer to buy two chainrings (46 and 36). The current chainrings are 130bcd. Can I buy two chainrings or do I need to buy a new crankset? If I can get away with buying two chainrings, what do I need to know to make sure they are compatible?
Problem 2: I have brake levers. I need brake calipers. What do suggest that will look good and function reliably.
Thanks for all of your help!!
10-04-12, 06:11 PM
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She might be uncomfortable without a saddle.
10-04-12, 06:16 PM
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Singlespeed Build---HELP!
You will commonly find those chain rings in 110bcd off old mountain/ touring cranks. There are plenty of 39, 42, 52 , maybe 48 rings in 130bcd from older road bikes
Last edited by hairnet; 10-04-12 at 06:26 PM.
10-04-12, 06:22 PM
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Need pictures of both sides of the drive-side crank to determine whether it can run two rings. Also you'll need some kind of tensioner in the back to pick up the chain slack between gears.
edit- Wait I'm stupid, it has two rings. Second part still applies.
edit- Wait I'm stupid, it has two rings. Second part still applies.
Last edited by seau grateau; 10-04-12 at 06:31 PM.
10-05-12, 05:11 AM
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10-05-12, 10:12 AM
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10-05-12, 10:53 AM
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My fiancé bought a failed attempt of a Trek fixed gear. I want to convert it to a manual two speed for his birthday. My budget is 200 for the parts I still need. I have already purchased Shimano 600ex brake levers and cable housing. Here is where I need help.
Problem 1: I would prefer to buy two chainrings (46 and 36). The current chainrings are 130bcd. Can I buy two chainrings or do I need to buy a new crankset? If I can get away with buying two chainrings, what do I need to know to make sure they are compatible?
Problem 2: I have brake levers. I need brake calipers. What do suggest that will look good and function reliably.
Thanks for all of your help!!
Problem 1: I would prefer to buy two chainrings (46 and 36). The current chainrings are 130bcd. Can I buy two chainrings or do I need to buy a new crankset? If I can get away with buying two chainrings, what do I need to know to make sure they are compatible?
Problem 2: I have brake levers. I need brake calipers. What do suggest that will look good and function reliably.
Thanks for all of your help!!
Are you wanting to keep the bike fixed? If so, you will not be able to use a chain tensioner and you're going to have a hard time tensioning the chain properly between two gears with vertical dropouts. The only real option then would be an eccentric rear hub, which is expensive. Also, how far apart are you wanting your two gears to be? Because if you run 46/36 chainrings, your cogs will probably need to be something like 16/26 so that your chainlength remains about the same between both gears. Then you'll have 46-16 and 36-26 combos which will give you gears of about 77 gear inches and 37 gear inches respectively. This is a huge gap and not of much use on the road.
If you are wanting to switch the bike to a freewheel, then you can use a tensioner, and you could keep the single chainring up front and use something like a White Industries DOS ENO freewheel which will give you two gear choices.
10-05-12, 01:33 PM
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Manual two-speed seems like a bad idea. That probably means chain tensioner and I figure if you need a chain tensioner might as well get a rear derailer instead, and if you get a rear derailer, might as well get a front derailer and if you have two derailers why not some shifters, then... yeah re-roadieing it sounds better than manual 2-speed to me.
If I got that bike and the chain wasn't too tight and I wanted to ride it right away I'd grap a front brake and road lever (probably two of those). Luckily that tape is pretty easy to retape (compared to cork) if you have some electrical tape to finish it with.
I'd be tempted to grind the teeth offa the big ring if I wanted it for commuter use.
Make sure that stem isn't out past min. insertion point. Get a saddle and roll out!
If I got that bike and the chain wasn't too tight and I wanted to ride it right away I'd grap a front brake and road lever (probably two of those). Luckily that tape is pretty easy to retape (compared to cork) if you have some electrical tape to finish it with.
I'd be tempted to grind the teeth offa the big ring if I wanted it for commuter use.
Make sure that stem isn't out past min. insertion point. Get a saddle and roll out!
10-05-12, 04:10 PM
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unless you are mechanically inclined, do not attempt a 2 speed setup.
10-06-12, 06:50 AM
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With smart placement of freewheels and chainrings, you can build a two-speed bike which is still, technically, a singlespeed. The only problem is, to switch to the other speed you have to pedal backwards.
You could also ask in the Bike Mechanics subforum.
You could also ask in the Bike Mechanics subforum.
10-06-12, 07:03 AM
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nagrom_ next time you stop by LV, ill buy you a few drinks. A few or a lot depending on what part of the week it is 
10-06-12, 07:21 AM
#22
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a ford pinto tubed out with a chevy small block stroked and bored with a roots style super?
