Page 1 of 2 1 2 LastLast
Results 1 to 25 of 33
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    22

    Rush: Carbon vs. Alloy.

    Recently broke a Cannondale frame and have the opportunity to upgrade to the aluminum Rush or pay $1200 for the carbon version. I have tested the carbon rush, but have never been on the alloy rush. Is there much of a difference between the two frames? ...weight?...stiffness?....performance?...durabili ty?...
    I wonder if the carbon is really worth the price to upgrade.

  2. #2
    mtbr member
    Reputation: sp3000's Avatar
    Join Date
    Mar 2007
    Posts
    558
    I can only add that the carbon is 300grams lighter, sorry I've only ridden the Alu.but I hear great things about the carbon.

  3. #3
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    Other than the weight savings the carbon is also stiffer in the front end so it tracks a little better and seems to damp vibration more. No problems with durability with mine, I have had some crashes into rocks and rocks thrown up into the downtube and all I have to show for it are some scratches and chips in the clearcoat. Put it one way, I liked my alloy Rush, but I love my Carbon, its a better bike.
    I would suggest going carbon if you can stretch your budget to it.

    Kevin

  4. #4
    mnt bike laws of physics
    Reputation: yogiprophet's Avatar
    Join Date
    Jan 2006
    Posts
    2,211
    I agree with you Flying W. But I have one more thing to add. The carbon version has the option to use the SI cranks. These cost a bundle. I don't know what you guys think, but man these cranks are the friggin' deal. I would have a very very hard time changing bike companies after being spoiled by these babies.
    When I put them on I instantly got faster and I haven't slowed down since, so it wasn't just some new parts euphoria.

    If you have the doe, go for it all

    Which frame did you break?

  5. #5
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    22
    After driving to Fruita and Moab for a mtb vacation, I cracked the Jekyll on the very first ride. I was very fortunate that cannondale was in Moab after a race. A mechanic hooked me up with his carbon rush for the week. I was very impressed with the bike then. But I figured if the alloy frame was as good I'd get it and save a little cash.
    The rush would definitely handle the 4-5 hr weekend rides as well as an occasional 24 hr race.
    Do you think an XL frame could be set up close to 25lbs?

  6. #6
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    The difference in weight is pretty small between sizes, most of the weight is in the swingarm and the shock! Given a medium Team is 23.7lb with pedals an XL should weigh under 25lb easy with the right componenet selection.
    YP is right on the money about the SI cranks, definately worth going for as the outset. With the carbon frame if you put in the adaptor you cant (shouldnt) try to remove it. The BB30 cranks are stiffer, lighter and stronger, plus the bearings last longer and are less likely to be affected by water. After the Durango 100, 100 miles of sloppy mud, rain and river crossings my team mates XTR bottom bracket in his Scalpel was toast, my Si bottom bracket still runs as smooth as it did when I got it. Plus FSA and now Truvativ and both producing their own BB30 cranks so you have more choices.

    Kevin

  7. #7
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    22
    Are the SI cranks aluminum or carbon? What price range?
    My local bike shop has done a great job so far by putting together an component upgrade kit.

  8. #8
    LA CHÈVRE
    Reputation: Dan Gerous's Avatar
    Join Date
    Feb 2004
    Posts
    9,378
    SI = BB30, the crankset interface.

    Cannondale has 2 mtb SI cranksets, a carbon (made by FSA) and an alloy (in house, Cannondale made) model. The alloy one (Hollowgram SL) is the king of cranks, it's probably the lightest mtb crankset on the market, among the stiffest, durability is top notch (even better with the ceramic bearings) and it has the option of a triple, 4 bolts 104 BCD spider or a double, 5 bolts 94 BCD spider which is offset to give a better chainline than just a triple without the granny ring. If I recall, the Hollowgram SL is in the 600-700$ range though, not cheap but you are getting the Formula 1 of cranksets here...

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  9. #9
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    22
    So, the integrated BB can't be installed after a traditional crankset/BB has been installed?
    Can a traditional BB be installed after an integrated BB was installed?

  10. #10
    mnt bike laws of physics
    Reputation: yogiprophet's Avatar
    Join Date
    Jan 2006
    Posts
    2,211
    Quote Originally Posted by wvnova
    So, the integrated BB can't be installed after a traditional crankset/BB has been installed?
    Can a traditional BB be installed after an integrated BB was installed?
    The mechanic who loaned you his XL Carbon Rush could take the insert out that is installed so that a traditional BB can be put into the frame. BUT, it is NOT recommended for the average bike shop mechanic to do this.
    If the mechanics name is Troy, I rode one of his XL's also. He is the one who told me he could do it.

    Yes, an insert can be put in any time if you wanted to put in a traditional BB.

    My Carbon Rush is an XL and it is around 25lbs. It is def. light enough to be competitive in any kind of XC race.

  11. #11
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    I think the FSA is or shortly will be available directly (ie not Cdale branded) aftermarket as a K-force light unit, but wont be cheap. Unless you are interested in saving the maximum amount of weight the Carbon Si crank is cheaper but still a great crankset. I know it adds to the price, but it has so many advantages over the outboard bearing style especially for a larger rider that I would say try to go that way if you can.
    I have been so impressed with mine that I know my next road bike purchase has to have a Si crankset. I rode a Super Six this last weekend which was an impressive ride........
    Plus with other companies like Specialized going the the BB30 standard I can see it growing in popularity among manufacturers.

    Kevin

  12. #12
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    22
    I was planning to go to the local bike shop and settle up the frame replacement. But, I'm glad I waited. Thanks for the info about the frames and BB. Anything else I should consider before making the decision?
    I am considering the carbon lefty sl, but the left rlc made for a very nice ride. After 7 years on the Jekyll, either lefty would have to be better than the 70mm headshock.

  13. #13
    Cannondale Snob
    Reputation: RiskEverything's Avatar
    Join Date
    Mar 2006
    Posts
    716
    Can't the alloy version of the Rush run the BB30 crankset as well? IIRC the '06 Team Replica had just that...
    '06 Cannondale Rush 1000 4" travel 27lbs
    '04 Cannondale F600 SOBE -STOLEN!
    '96 Cannondale Uber-V 6" travel 30lbs

  14. #14
    Huge Tracts of Land
    Reputation: Mtbrat's Avatar
    Join Date
    Jan 2004
    Posts
    165
    carbon all the way, it is so much better
    Haven MTB Park
    1997 F2000
    2004 F4000 SL
    2007 Carbon Rush 1 Team

  15. #15
    mnt bike laws of physics
    Reputation: yogiprophet's Avatar
    Join Date
    Jan 2006
    Posts
    2,211
    I have the SL Lefty and it is sweet. I would think that the RLC would be smoother because of the coil spring. I did not have an option when I got mine and man let me tell you it would be a hard decision for me. I do like the ability to change the spring value at the stroke of a shock pump and the 1/2 a pound difference, but the Fox internals and coil would be soooo sweet.
    Does anyone have any experience with both?

    RiskE, The '06 T.R. was the only alloy Rush to have the BB30 frame.

  16. #16
    LA CHÈVRE
    Reputation: Dan Gerous's Avatar
    Join Date
    Feb 2004
    Posts
    9,378
    Quote Originally Posted by RiskEverything
    Can't the alloy version of the Rush run the BB30 crankset as well? IIRC the '06 Team Replica had just that...
    Nope, when they introduced the Carbon Rush, they discontinued the BB30 alloy Rush... I'm hoping more and more frames will have a BB30 shell...

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  17. #17
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    Given the adaptor can be installed and removed from an alloy frame fairly easily I wish that Cannondale would spec the oversized bottomb bracket through most of their lineup rather than just the high end. What we need is some mid range cranks to fit the BB30 system. Perhaps with its increasing popularity we may see it more commonly. The old system was designed in the days of square taper steel spindles and just doesnt accomodate oversized axles without going to stop gap measures like the external bearings which have inherent disadvantages in sealing, friction and Q-factor.

    Kevin

  18. #18
    mtbr member
    Reputation:
    Join Date
    Apr 2006
    Posts
    439

    Carbon Rush frames from Indonesia

    Has anyone checked into ads for Rush carbon frames from overseas, like this one: http://topbikera.en.ec21.com/product..._Carbon_Cranks

    This particular ad has a min order of 5 units at $600/ to include carbon cranks, fox rp23 shock.

  19. #19
    mtbr member
    Reputation: Tackhammer's Avatar
    Join Date
    Dec 2006
    Posts
    428
    I've been planning for awhile to get the alloy Rush 5z as soon as my tax return comes in, now there is no way I can afford the carbon but after reading this thread it makes it seem like the alloy is not worthy - what's all this about bb30's and such? I'm not a bike guru or as knowledgable as some of you about these things, but is that a big deal? Is the alloy a good bike or not?

    Please help, I'm getting stressed.

  20. #20
    LA CHÈVRE
    Reputation: Dan Gerous's Avatar
    Join Date
    Feb 2004
    Posts
    9,378
    Quote Originally Posted by Tackhammer
    I've been planning for awhile to get the alloy Rush 5z as soon as my tax return comes in, now there is no way I can afford the carbon but after reading this thread it makes it seem like the alloy is not worthy - what's all this about bb30's and such? I'm not a bike guru or as knowledgable as some of you about these things, but is that a big deal? Is the alloy a good bike or not?

    Please help, I'm getting stressed.
    The carbon is terrific but the alloy one is by no mean a bad bike, it's still great and while BB30 (it's a different bottom bracket standard that uses bigger pressed-in bearings and a bigger, stiffer and lighter BB spindle) is great, it's not an absolut must have for most... The alloy Rush is still a very worthy bike to get and many people here are very happy with theirs.

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  21. #21
    mtbr member
    Reputation:
    Join Date
    Jan 2006
    Posts
    125
    I recently had the choice and chose Alu. An extra $1000 for 300 grams (maybe) of frame weight loss. Then there is the odd bottom bracket size. Talk about being tied in to Cannondale solutions (though I appreciate it is technically an interesting and light solution). I'd try not to get tied into a single manufacturer solution (yeah I don't have a lefty either )

    The bike will be down to around 25lbs with Fox forks and best of all there's no paint or carbon to scratch or chip (a real problem with my last bike)
    Last edited by wellmt; 01-23-2008 at 02:53 PM.

  22. #22
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    I really liked my alloy Rush (it was a very good bike) until I rode a Carbon....... It replaced both the alloy Rush and Scalpel in my arsenal.
    Bear in mind that I race seriously, so saving a couple of pounds is a big deal to me. If you were trail riding with a few events on the side for personal accomplishment then an alloy Rush with a Fox would be a great choice. And most of us rode quite happily back in the day with square taper bottom brackets before we had Octalink, then ISIS then external bearing cranks and now BB30.

    Kevin

  23. #23
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    204

    New question here.

    Quote Originally Posted by Flying Wombat
    ...an alloy Rush with a Fox would be a great choice...
    No love for the Lefty? Or are you just referring to the lower-ended Rushes?

  24. #24
    mad aussie
    Reputation: Flying Wombat's Avatar
    Join Date
    May 2004
    Posts
    1,124
    I like my Carbon SL but if someone was looking at the Rush 3Z I think the Fox F120 would be a good fork and work well with the bike. I may be a heretic but I dont think Cannondales HAVE to come with a Lefty.


    Kevin

  25. #25
    mnt bike laws of physics
    Reputation: yogiprophet's Avatar
    Join Date
    Jan 2006
    Posts
    2,211
    Quote Originally Posted by wellmt
    I recently had the choice and chose Alu. An extra $1000 for 300 grams (maybe) of frame weight loss. Then there is the odd bottom bracket size. Talk about being tied in to Cannondale solutions (though I appreciate it is technically an interesting and light solution). I'd try not to get tied into a single manufacturer solution (yeah I don't have a lefty either )

    The bike will be down to around 25lbs with Fox forks and best of all there's no paint or carbon to scratch or chip (a real problem with my last bike)
    Good for you man!

    To clarify, most of us ride the carbon for the way it feels not just the mass difference. The [I]odd[I] size bottom bracket is only odd because other companies are not intelligent enough(yet) to know a great thing when they see it(or don't see it because the bikes are too damn fast). Besides there is no down side to the SI crank system. No maintenance to speak of. Only lighter and stiffer by far.

    The minute I saw a lefty I understood the benefit(being a physicist and engineer). Most other forks, such as Fox, are held up by only on side of the fork(by that I mean there is only a spring on one side). The only material that holds the 2 sides of the lowers together are the quick release and the small bridge above the tire. That is not much material and those forks flex noticable more than a lefty upon compression and rebound. The lefty's main tube is way huge and is supported above and below the head tube which in the end yields a much stiffer suspension torsionally and laterally. Now that you can get it with Fox damping, it is only a matter of price that makes it not a complete no brainer.

Page 1 of 2 1 2 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •