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

Discuss light weight issues concerning road bikes & parts.
JerryLook
Posts: 119
Joined: Thu Dec 07, 2017 2:18 am

by JerryLook

g00se wrote:
Sat Apr 07, 2018 6:42 pm
Withe regard to the Cervelo expander plug, Cervelo use 3T forks and I've got the same sleeve in my 3T Rigida fork. The sleeve itself was about 7-8cm long and came with the star nut inserted. the instructions say to run the bike for a little while with a regular expander plug to work out where the steerer needs to be cut down to - then once cut, glue the sleeve into place. It's regular Araldite-like epoxy (24-hour dry). You have to alcohol wipe the steerer and sleeve before glueing.

I didn't weigh it but it's lighter than those big Deda-style bungs.

You could buy them here but they're out of stock. If you google it, you should be able to find it.

https://store.3tcycling.com/en/spare-pa ... t-181.html

Image

The shop that originally glued it made a mistake and later had to cut the steerer down futher AFTER the sleeve was glued it - but as it was only another 20cm, they pushed the star nut down and the sleeve still covers the whole stem area. I'm got the bike stripped down at the moment, so if you want, I could get the vernier callipers out and try to measure the insdie diameter of my steerer?
Thanks for the info. If you wouldn't mind measuring, that would be great. Then I would know for sure if the sleeve kit is an option
2010 Orbea Opal 54cm
6.6kg

by Weenie


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

by DamonRinard

Don't use anything the manufacturer won't approve.

Steerer tubes do break, of course you won't see failure rate data, but when it happens, serious injury can result. Off the top of my head, there have been recalls related to the upper part of the fork from such companies as Cervelo, Speciailized, Merida, Felt, and Trek had a technical bulletin (prompted by...failures?). The upper part of the fork steeerer is one of the few areas on a bike that does NOT have any strength test legally required. Merida mentioned this shortcoming during their recent fork recall.

Stress-wise, the steerer is highly stressed at (1) the bottom stem bolt and (2) the upper bearing split cone ring. (Of course in various loading situations there is high stress in other areas too, but these are the two related to the expander.) When the stem is slammed, the stem bolt and bearing ring are very close: stress from one adds to the other. That is why most OEM expanders expand to support the lower stem bolt: to reduce stress due to stem clamping.

That is why I recommend Don't use anything the manufacturer won't approve.
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 did send Orbea a email to see what they say. Even if I could use the newer style Orbea expander, it would save me around 25 grams over the one I have now
2010 Orbea Opal 54cm
6.6kg

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Lewn777
Posts: 363
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

g00se wrote:
Sat Apr 07, 2018 6:42 pm
Withe regard to the Cervelo expander plug, Cervelo use 3T forks and I've got the same sleeve in my 3T Rigida fork. The sleeve itself was about 7-8cm long and came with the star nut inserted. the instructions say to run the bike for a little while with a regular expander plug to work out where the steerer needs to be cut down to - then once cut, glue the sleeve into place. It's regular Araldite-like epoxy (24-hour dry). You have to alcohol wipe the steerer and sleeve before glueing.

I didn't weigh it but it's lighter than those big Deda-style bungs.

You could buy them here but they're out of stock. If you google it, you should be able to find it.

https://store.3tcycling.com/en/spare-pa ... t-181.html

Image

The shop that originally glued it made a mistake and later had to cut the steerer down futher AFTER the sleeve was glued it - but as it was only another 20cm, they pushed the star nut down and the sleeve still covers the whole stem area. I'm got the bike stripped down at the moment, so if you want, I could get the vernier callipers out and try to measure the insdie diameter of my steerer?
Thanks for putting this up, it certainly seems a safer option than mini-expanders.

User avatar
Lewn777
Posts: 363
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

DamonRinard wrote:
Sat Apr 07, 2018 9:19 pm
Don't use anything the manufacturer won't approve.

Steerer tubes do break, of course you won't see failure rate data, but when it happens, serious injury can result. Off the top of my head, there have been recalls related to the upper part of the fork from such companies as Cervelo, Speciailized, Merida, Felt, and Trek had a technical bulletin (prompted by...failures?). The upper part of the fork steeerer is one of the few areas on a bike that does NOT have any strength test legally required. Merida mentioned this shortcoming during their recent fork recall.

Stress-wise, the steerer is highly stressed at (1) the bottom stem bolt and (2) the upper bearing split cone ring. (Of course in various loading situations there is high stress in other areas too, but these are the two related to the expander.) When the stem is slammed, the stem bolt and bearing ring are very close: stress from one adds to the other. That is why most OEM expanders expand to support the lower stem bolt: to reduce stress due to stem clamping.

That is why I recommend Don't use anything the manufacturer won't approve.
Thanks. That's giving out information that could maybe save someone's life or prevent injury. :thumbup:

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

by JerryLook

I always thought slamming the stem would put less stress on the steerer, since you aren't putting so much pressure high up on the steerer. I’m not an engineer though, and am not totally sure how the whole thing works as far as the stress and pressure.
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

Less bending stress, but the clamping stress begins to overlap.
Basically, RTFM.
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

That makes sense with all the pressure in one area.

So, I got a reply from Orbea. They recommended to keep using the expander that came with the frame. They wouldn't even endorse using the newer (lighter) Orbea expander.

I’ll keep it in there for now, but keep it in mind for a place to lose 25 grams if I need to. I would consider using the a lighter expander of the same length. I don't want to risk it with anything lighter.

Thanks for everyone’s help. I’ll post some pics of the bike once I get it together. Got my BB today as well as an Omni Racer seatpost.
2010 Orbea Opal 54cm
6.6kg

Svetty
Posts: 519
Joined: Thu Mar 26, 2009 11:06 pm
Location: Yorkshire - God's Own Country

by Svetty

Lewn777 wrote:
Sat Apr 07, 2018 1:22 am
From what I've read and seen I wouldn't use a light-weight short expander plug unless the manufacturer officially okays it.

Image
If you look at the enve expander plug, it's this way because it's clearly what the engineers envision to be safe for their steerers.

Image
Obviously Cannondale engineers consider a small light short expander to be enough. Seems unusual, as I suspect most manufacturers would consider this insufficient, and would worry their steerer would get crushed or damaged. Clearly Cannondale have tested this with their steerers.

Image
However I look at the boring heavy long compression plug on my Fuji which looks like this, I'm tempted to switch it out and save weight, but something tells me that's not what the engineers would want, and I'm opening myself up to danger.
The Cannondale one seems to offer crush support at both stem bolts, the Enve one only seems likely to be long enough to fully support the upper bolt......

g00se
Posts: 34
Joined: Fri Feb 21, 2014 11:22 pm

by g00se

JerryLook wrote:
Sat Apr 07, 2018 8:28 pm
g00se wrote:
Sat Apr 07, 2018 6:42 pm
Withe regard to the Cervelo expander plug, Cervelo use 3T forks and I've got the same sleeve in my 3T Rigida fork. The sleeve itself was about 7-8cm long and came with the star nut inserted. the instructions say to run the bike for a little while with a regular expander plug to work out where the steerer needs to be cut down to - then once cut, glue the sleeve into place. It's regular Araldite-like epoxy (24-hour dry). You have to alcohol wipe the steerer and sleeve before glueing.

I didn't weigh it but it's lighter than those big Deda-style bungs.

You could buy them here but they're out of stock. If you google it, you should be able to find it.

https://store.3tcycling.com/en/spare-pa ... t-181.html

Image

The shop that originally glued it made a mistake and later had to cut the steerer down futher AFTER the sleeve was glued it - but as it was only another 20cm, they pushed the star nut down and the sleeve still covers the whole stem area. I'm got the bike stripped down at the moment, so if you want, I could get the vernier callipers out and try to measure the insdie diameter of my steerer?
Thanks for the info. If you wouldn't mind measuring, that would be great. Then I would know for sure if the sleeve kit is an option
For info, the 3T insert steerer diameter was 23mm

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

by JerryLook

The instructions with this Orbea expander are interesting. It shows they are more interested in supporting the bottom stem bolt it looks like. The way the expander is, the top bolt area would only be supported once the steerer is slightly compressed. I guess that is an acceptable amount of compression to whoever designed it.

Its interesting how the manufacturer recommends this big expander, but when I contacted a seller of the Omni Racer plug (I think its their authorized distributor) they said the plug is fine for my application. That plug only supports the top bolt. And only part of it with the stem slammed. I just think its funny that a company would assume liability for a part that the manufacturer doesn't recommend.

From what I have learned recently, I will be going with something that is less of a risk.

Btw, sounds like the Cervelo sleeve would fit my steerer. It is 23mm. I’ll have to find a weight for the sleeve, star nut, bolt, and top cap
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F7DE6398-E845-42CB-BC15-A3F6A973448D.jpeg
2010 Orbea Opal 54cm
6.6kg

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Lewn777
Posts: 363
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

The Cannondale one seems to offer crush support at both stem bolts, the Enve one only seems likely to be long enough to fully support the upper bolt......
The white section at the bottom gives crush protection for the lower stem bolt, but the upper black ribs barely even touch the steerer, so it's a very minimalist setup.
Last edited by Lewn777 on Thu Apr 12, 2018 2:33 pm, edited 1 time in total.

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

by JerryLook

What are you guys torquing your expanders to? I’ve heard just tight enough to keep it from slipping during bearing preload, and also torques from 8-9 Nm.
My other bike has a carbon fork with an alloy steerer, so I’ve never had to worry about over torquing.
2010 Orbea Opal 54cm
6.6kg

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

by JerryLook

Btw, I contacted 3T about the sleeve kit. They say they are no longer available, and that this expander will be available from now on. I emailed to ask how long it is. Looks long (like >50mm)

https://store.3tcycling.com/en/spare-pa ... t-514.html
2010 Orbea Opal 54cm
6.6kg

User avatar
Lewn777
Posts: 363
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

JerryLook wrote:
Wed Apr 11, 2018 7:52 pm
What are you guys torquing your expanders to? I’ve heard just tight enough to keep it from slipping during bearing preload, and also torques from 8-9 Nm.
My other bike has a carbon fork with an alloy steerer, so I’ve never had to worry about over torquing.
I torque everything to 4-5nm unless i get information from a more informed source that contradicts it. :D

by Weenie


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