Singlespeed & Fixed Gear - Another stupid chainline question...

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nimbuscrenel
08-18-09, 10:59 AM
I'm converting an older Raleigh road frame into a single speed. The rear hub is 126mm with a spin on freewheel. I'm thinking of getting the cheap Origin8 cranks which according to the website work with 103-107mm spindles. Would a cheap 107mm UN54 BB give me an acceptable chainline with this crank/hub setup? I've been reading threads for the last hour trying to figure it out, but I'm still not sure. Any help, suggestions, info, and insults are welcomed.


nimbuscrenel
08-19-09, 11:52 AM
was this question?:

a) too complex
b) tired
c) stupid
d) all of the above

Zachee
08-19-09, 01:27 PM
They reason you did not get any replies is because you did not provide enough information for anyone to help you.

But let me help you, help yourself.This (http://www.sheldonbrown.com/chainline.html) should have all the information you need to know about chainline. Good luck.


nimbuscrenel
08-19-09, 02:02 PM
They reason you did not get any replies is because you did not provide enough information for anyone to help you.

But let me help you, help yourself.This (http://www.sheldonbrown.com/chainline.html) should have all the information you need to know about chainline. Good luck.

Thanks for the response. I already read Sheldon's article and while very informative, I'm having a hard time figuring out what I need since I'm dealing with a bare frame with no BB or crank on it. I can't measure the existing chainline to figure out how different parts will change it. Also, what information did I not provide? I think the only thing I left out was that the hub is an old Miche Competition. I appreciate any help or suggestions...

slake707
08-19-09, 04:25 PM
First thing: Measure the chainline of the hub. Sheldons page will tell you how to do that.
Second: Figure out the chainline for the crank/BB combo.. I don't remember off the top of my head but I believe the 103mm gives a 42mm chainline with the origin8s .. the site selling will usually list, but u can also ask.
Third: With a square taper BB you can adjust the spindle length to match up with you hub (as long as it is not too short for clearance issues).. so if you need a 45mm chainline take the delta (3mm) multiply by 2 and add it the base known chainline spindle (eg 103 would use 109 for 3 more mm)

bicycle
08-19-09, 05:07 PM
+1 for sheldon brown

nimbuscrenel
08-19-09, 05:10 PM
thanks guys, i'll do some measurements on my hub tonight..... (does that sound a little dirty?) ;)

Scrodzilla
08-19-09, 06:59 PM
You're correct. A 103mm bb will give you 42 with the chainring on the inside and 107 will put your ring on the outside on those Origin 8 cranks. Same as Bulletproofs.

nimbuscrenel
08-20-09, 08:46 AM
You're correct. A 103mm bb will give you 42 with the chainring on the inside and 107 will put your ring on the outside on those Origin 8 cranks. Same as Bulletproofs.

thanks man, this is what I was looking for! :thumb: