Shave seat tube???

General Discussion about electric bicycles.
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JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Shave seat tube???

Post by JeffnAZ » Nov 20 2020 7:24pm

I'm getting a bike ready for a E build and one of my goals is to get the seat as low as possible. I'm thinking about cutting a little off the top of the seat tube to achieve this. Anyone try this???

Couple pics... was thinking shave just about a quarter inch (6mm) off the top. It should still clamp without cracking anything i think.
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Thanks for any wisdom.

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efMX Trials Electric Freeride   1 MW

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Re: Shave seat tube???

Post by efMX Trials Electric Freeride » Nov 20 2020 8:51pm

I did this with no regrets (so far)..
in my case used a bit larger frame for more battery space and a lower seat to bar height (than I would for a pedal only bike)..
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

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spinningmagnets   100 GW

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Location: Ft Riley, NE Kansas

Re: Shave seat tube???

Post by spinningmagnets » Nov 20 2020 9:45pm

I did that years ago, and no cracks have formed. Seat tube still works fine.

JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Re: Shave seat tube???

Post by JeffnAZ » Nov 21 2020 5:17am

Lol... thanks folks. Thought for sure this idea was going to be criticized. But no. I’m not the only person to think of cutting down a seat tube for a fraction of an inch of adjustment. Awesome.

JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Re: Shave seat tube???

Post by JeffnAZ » Nov 21 2020 5:23am

spinningmagnets wrote:
Nov 20 2020 9:45pm
I did that years ago, and no cracks have formed. Seat tube still works fine.
Thanks! Did you happen to extend or modify the split on the back of the seat tube that allows the tube to clamp down?

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spinningmagnets   100 GW

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Re: Shave seat tube???

Post by spinningmagnets » Nov 21 2020 7:53am

I wanted the seat as low as possible.
Slide the clamp down as low as it would go to mark a half-inch above it.
Remove the clamp
Slide an automotive hose-clamp onto the tube (to where the seat clamp was) to act as a guide for the hacksaw.
Cut the tube at the mark
Cut a slice down the back (angle grinder with a thin blade or Dremel), and it's done.

JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Re: Shave seat tube???

Post by JeffnAZ » Nov 21 2020 10:56am

spinningmagnets wrote:
Nov 21 2020 7:53am
I wanted the seat as low as possible...
Thanks, man. Enjoy your weekend!

JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Re: Shave seat tube???

Post by JeffnAZ » Nov 22 2020 11:51am

spinningmagnets wrote:
Nov 21 2020 7:53am
I wanted the seat as low as possible...
Thanks! Result is perfect. The hose clamp guide worked great! Removed 5/8" (~16mm). Could have gone lower but I couldn't bring myself to drill a hole in the flag.

Couple pics.
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spinningmagnets   100 GW

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Re: Shave seat tube???

Post by spinningmagnets » Nov 23 2020 1:43pm

I like that you drilled a hole at the base of the split-cut.

If you didnt, a "stress riser" might develop, and a possible crack might grow in unpredictable directions...

JeffnAZ   10 mW

10 mW
Posts: 20
Joined: Nov 20 2020 2:59pm

Re: Shave seat tube???

Post by JeffnAZ » Nov 23 2020 5:19pm

spinningmagnets wrote:
Nov 23 2020 1:43pm
I like that you drilled a hole at the base of the split-cut.

If you didnt, a "stress riser" might develop, and a possible crack might grow in unpredictable directions...
Thanks... exactly why I drilled it. Your help and interest is much appreciated.

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