Anyone running a short steerer expander plug on a Orbea Opal or Orca?

Discuss light weight issues concerning road bikes & parts.
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Lewn777
Posts: 374
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

Lelandjt wrote:
Sat Apr 14, 2018 9:03 am
JerryLook wrote:
Fri Apr 13, 2018 2:09 pm
I understand using a padded saddle (comfort is good) if they are trying to get up to the minimum weight, but why steel skewers? And if they do run full size expanders, why? There are so many parts on a bike that one could choose to make it heavier. There has to be a reason behind it.
Look at it differently: If the bike is right at the weight limit with Ultegra cassette, steel skewers, and full size expander why use a cassette that wears quicker, Ti skewers that might allow the wheels to flex more, and a skimpy expander (or none) that may not support the steerer as well when there's no weight loss to enjoy from these parts cuz you'd have to add the weight elsewhere to get back to minimum weight.
I really can't understand why you need to go out of your way to defend your ultra weight weenie ideas that contradict the engineers that design our bikes. I use titanium skewers that some people wouldn't use as they might consider that dangerous, yet I wouldn't bother crashing those other people's threads to with personal anecdotal evidence that I've used them for years and have been fine, just let those people have their 'belt and braces' uber safe party and let it slide. :)

Unless, of course you are an engineer and have real data and technical arguments to share.

by Weenie


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Lelandjt
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by Lelandjt

Huh? I'm explaining why a pro wouldn't use weight weenie parts that bring their bike under the weight limit.

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Lewn777
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by Lewn777

DELETE
Last edited by Lewn777 on Sun Apr 15, 2018 5:03 am, edited 1 time in total.

User avatar
Lewn777
Posts: 374
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by Lewn777

Loads of pro level aero bikes are in the 7-7.5kg range, especially if disk brake versions. Surely it would be an advantage for the bike to be lighter, but they don't start removing their expanders etc, probably because they don't think it's worth it. Same reason they don't run linked alloy cable outers and ti skewers.

JerryLook
Posts: 119
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

I got the bike put together. Its 16.4 lbs with mostly older Ultegra conponents. I have some Dura Ace parts, a different saddle, and different pedals that should bring it closer to 15 lbs.

I’m a weight weenie, but not a super duper weight weenie. I’ll be very happy with a reliable 15 lbs bike:)
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AEC8F7A9-D93C-4817-BB07-3C6A691AACD5.jpeg
2010 Orbea Opal 54cm
6.6kg

JerryLook
Posts: 119
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

So I have taken the bike for a 20 mile shakedown ride. There was a rattling coming from the headset area. After shaking things and holding cables etc trying to figure out what was rattling, I figured out it is the sleeve that sits on the expander. Basically the part that keeps the top stem bolt from crushing the steerer.

Even with stem bolts torqued to 5nm the sleeve still rattles around in there. I can pull it out without effort. So right now I just took it out. I figure if it isn't supporting the stem, it isn't really doing anything.

My question is, how tight would you have to torque the stem bolts to get this thing compressed in the steerer?
2010 Orbea Opal 54cm
6.6kg

DamonRinard
in the industry
Posts: 349
Joined: Fri Apr 29, 2011 8:32 pm
Location: Connecticut, USA

by DamonRinard

If you're using the expander shown in your photo of Orbea's instruction page, it looks like the top part isn't intended to support the top of the steerer. I think I can see clearance in their illustration.

In that case, adjust the bearings as usual, tighten the stem bolts (don't exceed their recommended torque), then tighten the top to prevent rattling.

Yes, it's easily removable, but stems walk on the steerer and the top part helps keep the stem in place and extend the time between headset adjustments.
Damon Rinard
Engineering Manager, Road Bikes
Cycling Sports Group, Cannondale
Ex-Kestrel, ex-Velomax, ex-Trek, ex-Cervelo

JerryLook
Posts: 119
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

The only way I can see to compress this sleeve (silver middle part in the pic) is to adjust the expander closer to the top of the steerer. Then is would be compressed between the top cap and expanding section of the expander.

I have the expander down in the steerer now so it expands in the bottom stem bolt area. Judging by the drawing, this expander is probably meant to be used with the stem at the top of the steerer. I should probably get a longer expander, or cut the steerer.
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C5F270CA-4F6A-4097-B3D8-BB0587FD5368.jpeg
2010 Orbea Opal 54cm
6.6kg

DamonRinard
in the industry
Posts: 349
Joined: Fri Apr 29, 2011 8:32 pm
Location: Connecticut, USA

by DamonRinard

I agree with your interpretation of the drawing: it's clear they don't want any spacers above the stem, and the bottom piece (expander) must support the bottom stem bolt.

Maybe contact Orbea again. It's not clear to me how that middle piece (silver) is supposed to work.
Damon Rinard
Engineering Manager, Road Bikes
Cycling Sports Group, Cannondale
Ex-Kestrel, ex-Velomax, ex-Trek, ex-Cervelo

JerryLook
Posts: 119
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

I think I should just use best judgement and get a taller expander. I know I can find one that is lighter than my current 70 gram unit, and also has the expander section from top to bottom.

Orbea doesn't really answer my questions, other than to say follow the directions, and use the parts that came with the bike. From a liability point of view, I guess it makes sense.
2010 Orbea Opal 54cm
6.6kg

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