# Weight weenie crank/bb combo...should I bother?



## patchito (Jun 30, 2005)

Looks as if I'm getting a new bike soon. It comes packaged with Dura Ace cranks. These are the conservative choice - stiff, reliable, durable. The weight weenie in me, however, wants some Pulsions with an American Classic bottom bracket. 

One thing I would rather _not_ due is constantly remove my cranks and fiddle with unreliable ISIS bottom brackets. I do this with my American Classic bb in my racing mountain bike, which I don't mind so much considering I ride it mostly when I race, but I intend to be riding and racing my roadie all the time. It needs to be a workhorse as well as a lightweigh, high performance machine. 

Should I bother with the Pulsions, or stick with what works? I want a sub 15lb bike, but I need to ride it.


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## DIRT BOY (Aug 22, 2002)

get the cranks and go with a more relaiable ISIS BB. 95% of ISIS BB are fine when used for road use.

Look in to the FRM or Token BB if you want real light weight. Or get an FSA Platinum Pro Ti on closeout or the new Ti MegaQuad (198g).

Or get some FSA TEAM ISSUE cranks in Octalink and run a DA BB.
I had a pair on my Capella and they were decently light @ 411g in the 170mm length.

So what bike are you gettng?


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## patchito (Jun 30, 2005)

DIRT BOY said:


> get the cranks and go with a more relaiable ISIS BB. 95% of ISIS BB are fine when used for road use.
> 
> Look in to the FRM or Token BB if you want real light weight. Or get an FSA Platinum Pro Ti on closeout or the new Ti MegaQuad (198g).
> 
> ...


Ok, you convinced me. I might stick with Am Classic, though, cuz I can replace the bearing.

What bike am I getting? You'll see.


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## DIRT BOY (Aug 22, 2002)

Come on! You where looking at the Blue RC4 right?

BTW: My RC6 rides like a dream! 272.2 miles so far and wow!
Stiff, but very compliant ride. Accelrates easliy out of coneers, climbs well and even makes brick paved sections on the roads feel smooth like butta!

My only complaints is, it seems to have very quick steering. Something I have to get use to going around corners fast.

I ma so happy with it. I have rriden a few carbon bikes here and there and this is up there with any. Only one I did not care for was a TREK Madone 5.2 and 5.2 SL. I LOVE the way the bikes looks and have been very happy with other TREK products in the past, but their carbon bikes fell really "dead." Same thing with the carbon MTB from them. Just kinda of dead feeling when riding it.

I would buy a TREK carbon frame in a heartbeat if it felt better.


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## C40 (Jan 29, 2006)

I was looking into an FRM BB and have a couple of questions:
1) Bolt size ? M15?
2) What type tools are necessary to install? I currenty have the FSA ISIS tool for install and removal.
3) Replaceable bearings? Easy to acquire? Do they come in a ceramic version?
4) Where can I purchase one?

Thanks!

Ian in SD



DIRT BOY said:


> Come on! You where looking at the Blue RC4 right?
> 
> BTW: My RC6 rides like a dream! 272.2 miles so far and wow!
> Stiff, but very compliant ride. Accelrates easliy out of coneers, climbs well and even makes brick paved sections on the roads feel smooth like butta!
> ...


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## FTF (Aug 5, 2003)

C40 said:


> I was looking into an FRM BB and have a couple of questions:
> 1) Bolt size ? M15?
> 2) What type tools are necessary to install? I currenty have the FSA ISIS tool for install and removal.
> 3) Replaceable bearings? Easy to acquire? Do they come in a ceramic version?
> ...


It uses standard isis tools, I'm pretty sure it's M15.

I have a FRMbb I could sell you for cheap. PM me for info.


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## DIRT BOY (Aug 22, 2002)

The bolts are M12!
Regular ISIS tools.
Replacable standard bearings, although a tool might be needed.
Any bearings shop should have they size and you can probaly find cermaic ones.

 CU2-BB ISIS Al 108 mm English 
01.01.02.002.04.01.01 <table border="0" cellpadding="0" cellspacing="0" width="525"><tbody><tr><td class="middleText" valign="top" width="50%">- ISIS Drive compatible
- Spindle is CNC machined from high quality 7075 light alloy
- Replaceable Oversized ball bearings
- Self-extracting bolts in light alloy included
- Easily serviceable
- BB Cups: BC-1,37” x 68 mm or M36 x 70 mm
 </td> <td class="middleText"> 
</td> <td class="middleText" valign="top" width="50%">Axle material: 7075 Light Alloy
Cup material: 7075 Light Alloy
Spindle Length: 108 mm
Bearings: 31x21,5x12 Double Race
Self-Extracting bolts: M12 in light alloy
Weight: 145 g (108 mm)
</td></tr></tbody></table>


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## C40 (Jan 29, 2006)

I've got a set of Stronglight pulsions and would like to keep the M15 cranks bolts since they also serve to remove the cranks from the bb themselves (nice). If I can figure out how to remove them cranks bolts then maybe I can start looking into BB's that don't require M15's.

Ian in SD


DIRT BOY said:


> The bolts are M12!
> Regular ISIS tools.
> Replacable standard bearings, although a tool might be needed.
> Any bearings shop should have they size and you can probaly find cermaic ones.
> ...


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## Juanmoretime (Nov 24, 2001)

*The one to use.*



C40 said:


> I've got a set of Stronglight pulsions and would like to keep the M15 cranks bolts since they also serve to remove the cranks from the bb themselves (nice). If I can figure out how to remove them cranks bolts then maybe I can start looking into BB's that don't require M15's.
> 
> Ian in SD


Here is the bottom bracket to use. It does have 15mm threads. Both mysel and another forum member Flying have been using this for a while with excellent results.

http://cgi.ebay.com/TOKEN-Ultraligh...71727QQcategoryZ56195QQtcZphotoQQcmdZViewItem


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