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Old 07-27-07, 01:13 PM   #1
Paupie
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upgrade ashtabula to better bottom bracket?

I found a near-mint old 6-speed steel Ross cruiser at a thrift shop for 20 bucks. It's not exactly what you'd call a "good" bike but I really like it for some reason; maybe good condition for a '70s bike, and because it seems really sturdy. I don't even mind that it weighs a ton because I'm pretty heavy myself. Anyway, when I took it apart I discovered it has one of these weird one-piece cranks, which I now know is an ashtabula. Can anyone tell me if I can upgrade it to a modern bottom bracket? Is it worth it? Thanks in advance.

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Old 07-27-07, 01:29 PM   #2
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Originally Posted by Paupie View Post
I found a near-mint old 6-speed steel Ross cruiser at a thrift shop for 20 bucks. It's not exactly what you'd call a "good" bike but I really like it for some reason; maybe good condition for a '70s bike, and because it seems really sturdy. I don't even mind that it weighs a ton because I'm pretty heavy myself. Anyway, when I took it apart I discovered it has one of these weird one-piece cranks, which I now know is an ashtabula. Can anyone tell me if I can upgrade it to a modern bottom bracket? Is it worth it? Thanks in advance.
If you're satisfied with the existing pedals, no burning need to change the BB. Those are very reliable, just a bit on the heavy side (and use oddball pedal threads, so your pedal options are highly limited.

See: http://sheldonbrown.com/opc

We have adaptor bushings that would let you install any modern bottom bracket in your frame:

http://harriscyclery.com/opc

Sheldon "Ashtabula" Brown
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Old 07-27-07, 01:31 PM   #3
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it doesn't sound as if you have much reason to upgrade, given that you don't seem to mind the weight too much (and the whole thing is heavy, and it wouldn't save much percentage-wise to put a more typical crankset on the bike).
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Old 07-27-07, 03:06 PM   #4
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I just did this with a Schwinn using a BMX adapter. I wanted to be able to use smaller chainrings for the hills around here. It saves some small amount of weight, but the bike is a tank so I doubt that will mater much. The adapter I got is a bit too long and the chain line in some gear combos is not real pretty, but it works.
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Old 07-27-07, 04:00 PM   #5
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+1 on the above posts. There isn't a really great reason to change the crank for a Ross. The Ross bicycles were mostly heavy even compared with it's 1970's vintage colleagues.

The good thing about the ashtabula cranks is that they are pretty fool-proof. You don't need a crank puller to get them off. You don't have to worry about striping any threads or the crank arm getting loose on the spindle. Etc.
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Old 07-27-07, 04:07 PM   #6
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thanks for the info folks

Based on what you guys are saying I will probably just leave it the way it is. I was able to put the kind of platform pedals I like on it. I would probably prefer a smaller chainring though so I'll ask at lbs.

Paul
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