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Re: Post your Small budget weight saves

Posted: Wed Nov 21, 2018 9:26 pm
by WILLIAMDENYS
wheelsONfire wrote:Exactly!
Still strong enough?


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Re: Post your Small budget weight saves

Posted: Wed Nov 21, 2018 9:27 pm
by themidge
dmp wrote:
Wed Nov 21, 2018 7:58 pm
Changing to Ti cleat bolts and washers for Look saved (if I remember correctly) less than 10g. But weight savings wasn't the reason I did it- it was because the Ti fittings don't rust, and cleat bolts are highly subject to rust.
This is a great excuse for doing a little bit of bolt tuning, I like the idea of have a bike that is as non-corrosive as possible (so bolt-tune your winter bikes everyone! :D ).
Places I can think of where bolts are likely to corrode eventually:
- brake bolts/recessed nuts, these are the worst for rusting
- cleat bolts, as mentioned already
- limit screws
- bottle cage bolts if left unattended long enough
- not bolts, but the steel axle of quick release skewers can suffer

Re: Post your Small budget weight saves

Posted: Wed Nov 21, 2018 9:27 pm
by Weenie

Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 12:52 am
by Stendhal
maxxevv wrote:
Tue Nov 20, 2018 7:50 am
Stendhal wrote:
Tue Nov 20, 2018 3:49 am
My suggestion -- and I am surprised no one has mentioned it yet, to my knowledge -- is to fill your tires with helium instead of air. Helium is lighter than air so you'll save some grams. Plus, you may be able to float up the climbs, ahead of your club ride friends. (Why else do you think Ridley named its climbing bike the Helium)? Also, at coffee stops, you can delight your friends by taking a nip from the tire valve and speaking in a squeaky voice.
Except that you can't use helium on normal rubber tubes nor tyres ....
True, unless you line the tire and tubes with mylan. I'm surprised this hasn't happened yet

https://en.wikipedia.org/wiki/Lifting_gas

As the article states, it would not help as much, but you could use neon instead. As a side benefit, your tires will glow in the dark!

Thinking about this further, now we know why Miguel Angel Lopez was not able to keep up with Chris Froome on the mad climbs up the Sestriere on stage 19 of this year's Giro. Lopez rides for the Astana team, on Argon 18 bikes. Obviously they were filling their tires with argon, which is heavier than air.

All in good fun! Seriously, wouldn't it be the height of weight weenism \ First World optimization to develop lighter than air tire systems? Maybe this is occurring in secret, like the secret motors inside wheels "discovered" by the Italian press. Call the UCI -- there could be Air Doping going on!

Post your Small budget weight saves

Posted: Thu Nov 22, 2018 1:02 am
by C36
Helium is not new. If I recall properly Merckx did his hour record with helium in the tubulars.
The molecules are so small that they pass though the rubber and pressure drop is really quick.


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Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 1:11 am
by Stendhal
C36 wrote:
Thu Nov 22, 2018 1:02 am
Helium is not new. If I recall properly Merckx did his hour record with helium in the tubulars.
The molecules are so small that they pass though the rubber and pressure drop is really quick.


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That's so cool! Proof again that Eddy Merckx > us mere mortals.

Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 1:22 am
by Lewn777
I would be very careful about cutting seat posts and using small and light expanders. Likely you'll save 50g-100g between them but it could cost you your frameset.

The stem bolts need to be supported and some manufacturers recommend their OEM expanders only. Using a small lightweight expander could void your warranty and cause undue unintended stress on your steerer. Some manufacturers are okay with small and light expanders but most are not.

Some manufacturers demand that you use at least 10cm or even no more than 10cm inside the frame. Therefore if you cut a shorter seatpost than the OEM one even if you are longer than the marked minimum insert you can void your warranty. Some bikes are well reinforced around the seat post and top of the seat stays and brake bridge but some aren't. If your frameset or bike comes with a stock seat post than isn't a boat anchor I'd just leave it. If it came without one or was heavy find a nice one but measure 10cm inside the frame and ignore the minimum insert mark, any weight saved is a bonus.

Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 1:28 am
by mag
You may seal the frame and fill it with Helium as well ;-)

Anyway, drillium!

Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 3:44 pm
by WILLIAMDENYS
Lewn777 wrote:I would be very careful about cutting seat posts and using small and light expanders. Likely you'll save 50g-100g between them but it could cost you your frameset.

The stem bolts need to be supported and some manufacturers recommend their OEM expanders only. Using a small lightweight expander could void your warranty and cause undue unintended stress on your steerer. Some manufacturers are okay with small and light expanders but most are not.

Some manufacturers demand that you use at least 10cm or even no more than 10cm inside the frame. Therefore if you cut a shorter seatpost than the OEM one even if you are longer than the marked minimum insert you can void your warranty. Some bikes are well reinforced around the seat post and top of the seat stays and brake bridge but some aren't. If your frameset or bike comes with a stock seat post than isn't a boat anchor I'd just leave it. If it came without one or was heavy find a nice one but measure 10cm inside the frame and ignore the minimum insert mark, any weight saved is a bonus.
Does the smaller expander destroy your tube because you tighten your handlebar where there is no pug inside?


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Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 5:22 pm
by pdlpsher1
dmp wrote: Changing to Ti cleat bolts and washers for Look saved (if I remember correctly) less than 10g. But weight savings wasn't the reason I did it- it was because the Ti fittings don't rust, and cleat bolts are highly subject to rust.
+1. I got my Shimano cleat bolts and plates on eBay and shipped from China. Very high quality and they won’t rust.



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Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 5:36 pm
by pdlpsher1
WILLIAMDENYS wrote: Does the smaller expander destroy your tube because you tighten your handlebar where there is no pug inside?


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Yes. Most stem clamps are 40mm tall. You need an expanded that’s at least 45mm tall.


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Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 5:37 pm
by WILLIAMDENYS
pdlpsher1 wrote:
WILLIAMDENYS wrote: Does the smaller expander destroy your tube because you tighten your handlebar where there is no pug inside?


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Yes. Most stem clamps are 40mm tall. You need an expanded that’s at least 45mm tall.


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Oh okay so those tiny ones are bad


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Re: Post your Small budget weight saves

Posted: Thu Nov 22, 2018 11:52 pm
by Lewn777
WILLIAMDENYS wrote:
Thu Nov 22, 2018 5:37 pm
pdlpsher1 wrote:
WILLIAMDENYS wrote: Does the smaller expander destroy your tube because you tighten your handlebar where there is no pug inside?


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Yes. Most stem clamps are 40mm tall. You need an expanded that’s at least 45mm tall.


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Oh okay so those tiny ones are bad


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Not always. It depends on the manufacturer, but as a general rule, yes. There are some good threads about this, I should dig them out.

Re: Post your Small budget weight saves

Posted: Fri Nov 23, 2018 12:07 am
by dereksmalls
Tune cable housing

Re: Post your Small budget weight saves

Posted: Fri Nov 23, 2018 1:08 am
by C36
dereksmalls wrote:Tune cable housing
Read a bit about them but never seen them. What makes them light and anything special using them?


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Re: Post your Small budget weight saves

Posted: Fri Nov 23, 2018 1:08 am
by Weenie

Re: Post your Small budget weight saves

Posted: Fri Nov 23, 2018 1:19 am
by 2lo8
Stendhal wrote:
Thu Nov 22, 2018 12:52 am
maxxevv wrote:
Tue Nov 20, 2018 7:50 am
Stendhal wrote:
Tue Nov 20, 2018 3:49 am
My suggestion -- and I am surprised no one has mentioned it yet, to my knowledge -- is to fill your tires with helium instead of air. Helium is lighter than air so you'll save some grams. Plus, you may be able to float up the climbs, ahead of your club ride friends. (Why else do you think Ridley named its climbing bike the Helium)? Also, at coffee stops, you can delight your friends by taking a nip from the tire valve and speaking in a squeaky voice.
Except that you can't use helium on normal rubber tubes nor tyres ....
True, unless you line the tire and tubes with mylan. I'm surprised this hasn't happened yet

https://en.wikipedia.org/wiki/Lifting_gas

As the article states, it would not help as much, but you could use neon instead. As a side benefit, your tires will glow in the dark!

Thinking about this further, now we know why Miguel Angel Lopez was not able to keep up with Chris Froome on the mad climbs up the Sestriere on stage 19 of this year's Giro. Lopez rides for the Astana team, on Argon 18 bikes. Obviously they were filling their tires with argon, which is heavier than air.

All in good fun! Seriously, wouldn't it be the height of weight weenism \ First World optimization to develop lighter than air tire systems? Maybe this is occurring in secret, like the secret motors inside wheels "discovered" by the Italian press. Call the UCI -- there could be Air Doping going on!
Realistically (as realistic as helium in tires go) you're not trying to get lift force though. Tires are under pressure. Assuming you have a constant pressure, according to the ideal gas law, (assuming ideal) PV=nRT. Assuming V is constant because of tire size, T is constant because it's not going to change based on gas, and R is a constant, that means P is proportional to n. The molar mass of helium is 4g/mol. The molar mass of air is 29g/mol.

For a 700x23 tire, experimentally, each bar/atm of air adds about 1g ( https://2lo8.wordpress.com/2016/06/24/j ... -than-air/ ), which should be directly proportional to the moles of air in the tire, and the mass directly proportional to the moles of air. So assuming that I didn't forget how to do stoichiometry, if you would normally have ~14g of air in your tires, that would be ~2g with helium. That would be about equivalent to 1 bar/atm of air pressure at sea level since that was experimentally determined to be ~1g/bar per tire.