Cervelo R5 3D30 to R9100 crankset

Discuss light weight issues concerning road bikes & parts.
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CerveloFTW
Posts: 1
Joined: Wed Jan 04, 2017 4:22 pm

by CerveloFTW

My bike is in the shop at the minute having a full strip down/service etc

I want to put my new R9100 crank on this frame, but my LBS has said i need a new BB, fair enough, i wanted it changed anyway, but he has said it is an extra £140, now that seems like a high markup to me for a BB, i am already paying £170 for the service, taking out and re-greasing was part of the price

Can anyone confirm that the below product is what i need, with no other shims necessary...

Rotor Press Fit 46-24mm Convertor Steel Bearings

http://www.sigmasport.co.uk/item/Rotor/ ... rings/2KFI

Thanks and happy new year

goodboyr
Posts: 1388
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

This can be used as well. Then you retain your existing BB in case you ever want to go back to the bbright crank set.

http://www.totalcycling.com/en/ca/Wheels-Manufacturing-BBRIGHT-adapter-for-Shimano-24mm-Spindle-Cranks/m-21200.aspx

by Weenie


wingguy
Posts: 3739
Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

The internal sleeve with that one is sized for a PF30 shell width (I think). There is a specific BBright system with essentially the same bearings here http://www.sigmasport.co.uk/item/Rotor/BBright-to-Shimano-Converter/SQP?s=1

£140 is nuts, unless he's quoting you for a ceramic BB :noidea:

hambini
Posts: 128
Joined: Tue Nov 15, 2016 8:13 am

by hambini

CerveloFTW wrote:My bike is in the shop at the minute having a full strip down/service etc

I want to put my new R9100 crank on this frame, but my LBS has said i need a new BB, fair enough, i wanted it changed anyway, but he has said it is an extra £140, now that seems like a high markup to me for a BB, i am already paying £170 for the service, taking out and re-greasing was part of the price

Can anyone confirm that the below product is what i need, with no other shims necessary...

Rotor Press Fit 46-24mm Convertor Steel Bearings

http://www.sigmasport.co.uk/item/Rotor/ ... rings/2KFI

Thanks and happy new year


I had exactly the same scenario as this and sigma recommended the same bottom bracket to me. The rotor bottom bracket is utter rubbish. The shimano crank has a 24mm axle and the standard cervelo housing is a 46mm hole. You will probably find the rotor bottom bracket creaks like crazy - mine did so I ended up designing and making my own. After disassembling it I found the rotor BB had terrible manufacturing tolerances and the Cervelo shell wasn't right either. I ended up going with a one piece design, it's a lot stiffer, doesn't creak and I ride it all year round. The only thing I change is bearings every 6 months.

Here are a few videos I did about it. Everything about Cervelo BBright https://youtu.be/9IlWUVfAVEE

Here's the bottom bracket that I made https://youtu.be/b5E3nDLUu4M

And here's how to fit it into a Cervelo S5 - same BB setup https://youtu.be/PxN2X59VWA0?list=PLWIl ... oG7Tbn97uz

Additionally, I dislike it when companies fleece the consumer so here's some drawings if you want to make your own

http://www.hambini.com/downloads/ go down to BBright

I'm not very good at writing stuff but here's the page with my findings http://www.hambini.com/cycling/cervelo- ... -creaking/


Hope that assists you

Hambini

em3
Posts: 887
Joined: Tue Dec 23, 2008 2:57 pm
Location: NYC

by em3

...not sure where your LBS is coming up with the absurd £140, I would very much question that.

Also, make sure that the mechanic is installing using Loctite 609 or stronger and activator....no exceptions! If they won't install with the Loctite then take it elsewhere. EM3
______________

richievet
Posts: 18
Joined: Mon Dec 26, 2016 8:12 pm

by richievet

I'm on my third rotor pressfit in 4 years.. creaky creaky! The 46-24 one fits my 2012 R5 and cost £30 ish

em3
Posts: 887
Joined: Tue Dec 23, 2008 2:57 pm
Location: NYC

by em3

richievet wrote:I'm on my third rotor pressfit in 4 years.. creaky creaky! The 46-24 one fits my 2012 R5 and cost £30 ish


Got Loctite??
______________

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Cheers!
Posts: 1423
Joined: Sat Aug 05, 2006 2:29 am
Location: Mountain View, California
Contact:

by Cheers!

that price doesn't sound outrageous...

https://www.bbinfinite.com/products/bbr ... it-shimano

is around that price.

upside
Posts: 601
Joined: Fri Mar 09, 2007 1:26 am
Location: USA

by upside

Wheels Manufacturing has a adapter for about $30... Any thoughts on that. I have used those on a few bikes without any issues,

hambini
Posts: 128
Joined: Tue Nov 15, 2016 8:13 am

by hambini

The problem with an adaptor is you have an tolerance stack up which means you are more liable to get creak. It also relies on plastic to transmit a part axial and radial load. Plastic is not good at that.

If you are not shooting up hills or on very light use I think an adaptor would be okay. A lot of my customers say once they've had an engineered bottom bracket they are reluctant to go back to anything else because they can detect the stiffness difference.

Hambini

by Weenie


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