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Can I shim a seatpost/seat tube?

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Can I shim a seatpost/seat tube?

Old 07-22-22, 06:36 AM
  #26  
smd4
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Originally Posted by sovende View Post
Using a shim to get a proper fit between a seat tube and seat post isn’t nearly as “cheap” or blasphemous as some might like to think.
Yes, it is. On anything other than a kid's bike. It's a shortcut, pure and simple.
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Old 07-22-22, 03:07 PM
  #27  
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Originally Posted by smd4 View Post
Yes, it is. On anything other than a kid's bike. It's a shortcut, pure and simple.
On a new, relatively expensive bike, I’d tend to agree but for someone rehabbing a classic / vintage bike that has suffered some level of abuse, misuse or disuse and needs a replacement seat post to bring it back to its former glory, using a shim would, IMHO & perhaps that of others, be completely acceptable. Restoration to museum quality would be an exception.
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Old 07-31-22, 09:02 PM
  #28  
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Originally Posted by smd4 View Post
Yes, it is. On anything other than a kid's bike. It's a shortcut, pure and simple.
Author and philosopher Robert M. Pirsig wrote an entire book, basically about why you are wrong! I am not making this up (although I am exaggerating a bit).

Although Zen and the Art of Motorcycle Maintenance was a popular novel, it was also assigned reading in my engineering class. It has a lengthy scene about a shim. You should read it.
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Old 07-31-22, 09:07 PM
  #29  
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Originally Posted by Fredo76 View Post
Author and philosopher Robert M. Pirsig wrote an entire book, basically about why you are wrong! I am not making this up (although I am exaggerating a bit).

Although Zen and the Art of Motorcycle Maintenance was a popular novel, it was also assigned reading in my engineering class. It has a lengthy scene about a shim. You should read it.
Shims are shortcuts. Nothing wrong with them, but shortcuts nonetheless.
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Old 07-31-22, 09:32 PM
  #30  
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To make up for a 0.2mm difference in a seat post size I did a temporary fix of using a shim made of Beer Can aluminum about 6"/15cm long 3/4"/2cm wide. Never did get another seat post and the shim is still doing just fine after 10 years...

Originally Posted by smd4 View Post
You guys are the cheapest people I know. Shims? Really?? Pry open your wallets and buy the correct size seatpost. Sell the wrong one on eBay. Sheesh.
Of course you are right and I agree... But then I would have to turn in my "Cheap Bastard" membership card... Ha
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Old 07-31-22, 10:14 PM
  #31  
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Originally Posted by smd4 View Post
Yes, it is. On anything other than a kid's bike. It's a shortcut, pure and simple.
Maybe a beercan shim, but they sell shims especially designed and machined for this purpose and it is an accommodation more than a shortcut. You likely wouldn't even notice.
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Old 07-31-22, 11:17 PM
  #32  
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I was reading the fine print that came with my Problem Solvers 0.7mm shim. It says you should not use it with a carbon seat post, or a carbon frame. (I don't think this is specific to any particular diameter shim or thickness of shim that they make. I think it is a general directive. It does make sense because a shim focuses a force on a smaller area).
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Old 07-31-22, 11:19 PM
  #33  
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Originally Posted by smd4 View Post
Shims are shortcuts. Nothing wrong with them, but shortcuts nonetheless.
Unfortunately, it is worse than you are saying (see above).

Reluctantly, I will be taking your advice.
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Old 08-01-22, 04:36 AM
  #34  
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Didn't even enter my mind. Another reason not to buy a carbon-fibre frame! You might need to use a shim! Or a bike stand...
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Old 08-01-22, 05:36 AM
  #35  
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Originally Posted by Fredo76 View Post
Didn't even enter my mind. Another reason not to buy a carbon-fibre frame! You might need to use a shim! Or a bike stand...
Ti frame. Carbon post.
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