Framebuilders - Rear spacing - Can you stretch 120mm to 133mm?

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Mr_Christopher
11-26-08, 11:39 AM
Or is that too big of a stretch? We're talking about a cromo frame.
Chris
unterhausen
11-26-08, 09:18 PM
generally, yes
Presumably you actually want to hit either 130 or 135. 133 is the midpoint so you can use either. You can bend the stays that much and get the wheel in, generally. You will need to reset the drops a little. From a frambuilding perspective this is kinda a hack job. My normal goal is to get things closer to an ideal. I would search out the proper hub, or get a different frame.
Mr_Christopher
11-27-08, 06:44 AM
Point taken. Thanks
Chris
Sorry to sound preachy, was just trying to get to the point that you can do it, comes up on the touring board all the time, and there the need for part replacement may trump other concerns. At the same time you are taking a risk that you will end up worse off than you started out.
unterhausen
11-28-08, 04:15 PM
My answer assumes it's an older bike with 120mm spacing stock from the factory. Newer, thinner tubes may buckle. For whatever reason, while building a frame the rear spacing tends to shrink, so there is some likelihood that a frame has already been bent. 7mm per side on a robust steel tube is nothing. I recently had this discussion at my favorite bike shop. They were not amused by my position on the topic.
I've seen frames bent more than that, although thank goodness none of mine. If you search the internet for framebuilding pictures, you will probably find some pictures of buckled downtubes.
Mr_Christopher
11-28-08, 04:16 PM
Sorry to sound preachy, was just trying to get to the point that you can do it, comes up on the touring board all the time, and there the need for part replacement may trump other concerns. At the same time you are taking a risk that you will end up worse off than you started out.
You didn't sound preachy at all, in fact you helped me come to my senses :-)
Chris
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