How light could I get this seatpost?

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themidge
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Joined: Fri Jan 13, 2017 4:19 pm
Location: underneath sweet Scottish rain

by themidge

So, the seatpost I have on my Cannondale weighs 177.5g, not bad for a £40 ebay seatpost, but I want to pick the brains of WW to see what I could do about tuning it. Of course, I could just buy a new, lighter post, but that would be expensive and I like how minimal this one is for a 0-setback post (no long bolts and a cross beam poking out way beyond the underneath of the saddle), so for the moment, I'd like to see what I could do with this one.

Here's the bare post:
Image
Not the lightest out there, I think it has an aluminium head for the bolts to be secure. It was 400mm long, now cut down to 300mm, I could cut some more off, but I'd rather not until I stop growing :D. Not much to be done here I don't think, so what about the rest..?

Stock cradle:
Image
Not a bad weight actually, it seems most cheap carbon ones are about the same. However, Smud makes a 9 gram one. Has anyone tried it? It's a bit expensive (~£26) for a 4g saving, so are there any cheaper alternatives that will actually save some weight?

Stock yokes:
Image
Might these be an opportunity to save some weight with Ti or lighter alloy ones? I found some J&L ones on fleabay at 12g for £10, anyone know of any others?

Stock bolts:
Image
I have no idea what these are made of, they don't respond to a fridge magnet so perhaps not steel? In any case, I'm not familiar with bolt weights, so are these heavy, or as light as I need bother with, or somewhere in between?

The post also needs these two funny washers for the bolts, but I think these might have to stay as lighter replacements probably don't exist(?):
Image

Thought I ought to make a proper weight focused thread :wink:

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alcatraz
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Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

If it's carbon then cutting it down doesn't save alot of weight. I think the weight is around the clamp area, either the clamp itself or the tube reinforcement there.

Right now in china the lightest cheap seatposts are 135gr for 350/27.2mm 0setback. It's around 15-20usd. Maybe try that one.

danbjpa
Posts: 359
Joined: Sun Aug 08, 2010 5:12 am
Location: Brasil

by danbjpa

+1

You will spend more and save less weight buying cradle and yokes than a new cheap and light seatpost.
My ~60$ Hylix (25.4/400mm) weigh 154g (uncut). ‘Climax’ seatpost (27.2/350mm) weigh 121g (stock/untuned) and 101g after tuned (brand sanded, cut, yokes and cradle replaced - MCFK cradle + POP yokes saved ~8g over the Climax stock parts)
I’m 45kg - no problem so far.

betwo
Posts: 16
Joined: Tue Apr 17, 2018 6:40 pm

by betwo

alcatraz wrote:
Mon Sep 24, 2018 1:43 am
If it's carbon then cutting it down doesn't save alot of weight. I think the weight is around the clamp area, either the clamp itself or the tube reinforcement there.

Right now in china the lightest cheap seatposts are 135gr for 350/27.2mm 0setback. It's around 15-20usd. Maybe try that one.
you have the link? thanks

alcatraz
Posts: 4064
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

betwo wrote:
Mon Sep 24, 2018 6:34 am
alcatraz wrote:
Mon Sep 24, 2018 1:43 am
If it's carbon then cutting it down doesn't save alot of weight. I think the weight is around the clamp area, either the clamp itself or the tube reinforcement there.

Right now in china the lightest cheap seatposts are 135gr for 350/27.2mm 0setback. It's around 15-20usd. Maybe try that one.
you have the link? thanks
https://m.aliexpress.com/item/328140245 ... form=msite

Seems to be 130gr. Price is with international shipping. You might find cheaper from other sellers. (They all say they make it themselves, it's all bullshit. They get it from the local supplier.)

JerryLook
Posts: 305
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

That post you linked comes out to around 33$ with shipping and paying with Paypal. Seems like a pretty good deal. I might buy one to try out.

I agree that buying a lighter Chinese post is probably cheaper than tuning the one you have. But it might be close.

I wonder what the weight limit is on these super light posts. For a 85kg guy like myself, it might be pushing it. For the above 45kg poster, I see no issues with a 100 gram seatpost.
2010 Orbea Opal 54cm
5.97kg

alcatraz
Posts: 4064
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

In china this is being sold for around 25 usd. Check the different sellers on alixpress. The link was just the first one I saw.

SQUICCHI
Posts: 75
Joined: Fri Aug 21, 2015 7:06 pm

by SQUICCHI

I don't trust the China carbon stuff, especially because they don't make any safety test

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themidge
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Joined: Fri Jan 13, 2017 4:19 pm
Location: underneath sweet Scottish rain

by themidge

Boi, I wan't expecting another reply on this thread. I think the main problem most people have is with the lack of quality control with chinese carbon rather than safety tests. For what it's worth, my seatpost hasn't got lighter on purpose or by accident :D.

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Lewn777
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by Lewn777

For anyone reading this thread looking to save weight on a post change the underseat bolts or clamps to titanium from steel.
Remember to leave at least 10cm of seat post in your frame, lots of carbon fibre bikes can fail around the seat stay or seatpost junction and a seatpost that's too short just puts more pressure on this area. Esepcially important if you weigh over 75kg, I wouldn't even cut an OEM carbon seatpost.

charirider
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by charirider

Del
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by Weenie


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