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Why would you NOT buy this bike?

ct8282ct8282 Posts: 414
edited June 2013 in Road buying advice
So assuming you had the money, and were looking for a bike to ride distance comfortably, why would you not buy this bike....

http://www.evanscycles.com/products/bmc ... e-ec043706

I guess my mine line of enquiry is in relation to the carbon v Alu discussion. I realise most people would automatically expect you to buy a carbon frame when you're into big bucks, but why? We hear this word compliance a lot but what exactly does it mean when it comes to really riding a bike? BMC claim this frame is very compliant and the geometry will swallow road bumps and vibrations as good as a carbon frame. Will it really?

So, why would you not buy this bike if you have £3600 to spend? Just because its Alu?
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  • lawrenceslawrences Posts: 1,011
    Because the spokes are almost thicker than the seatstays. :o
  • Barrzy257Barrzy257 Posts: 411
    For that money, you could get a custom frame
  • ct8282ct8282 Posts: 414
    lawrences wrote:
    Because the spokes are almost thicker than the seatstays. :o

    So what?
  • ellj22ellj22 Posts: 122
    Longevity could be an issue, they have butted the tubes in a way to allow vertical deflection. Aluminium alloys are not usually great when it comes to fatigue compared to other frame materials. Carbon is also quite good at absorbing vibration, aluminium generally is not. Also an aluminium frame will never compare on weight with carbon for frames of a similar strength/stiffness/ fatigue resistance.
    I'm surprised they have chosen to butt rather than hydroform the frame as hydro forming generally allows greater flexibility in design however more expensive especially for short production runs.
    However saying this I have an older BMC as my training bike. Fun to ride but one of the most rigid feeling bikes I have ridden, the back end skips around like nothing else when sprinting but that just adds to its charm.
  • timboothtimbooth Posts: 160
    The fact that you even phrase the question that way says something, does it not? Would you pose the same negative-default question about NOT buying a carbon-framed bike - if not, why? Ignore what BMC and Evans say - they're trying to sell it! Aluminium is a poor choice compared to modern carbon frames.
  • kangarougekangarouge Posts: 205
    Why would I not buy it? Because its ugly at the back end! Do you really want to spend money on an ugly duck?
  • No SweatNo Sweat Posts: 103
    Maybe because you're limiting your choice to Alu or composite?

    With that sort of money you could buy something beautiful, and which would probably last longer, made from 953 or titanium......
  • rolf_frolf_f Posts: 16,015
    No Sweat wrote:
    With that sort of money you could buy something beautiful, and which would probably last longer, made from 953 or titanium......

    No reason why Ti or 953 would last longer than cf.
    Faster than a tent.......
  • KonkyWonkyKonkyWonky Posts: 186
    ellj22 wrote:
    Longevity could be an issue, they have butted the tubes in a way to allow vertical deflection. Aluminium alloys are not usually great when it comes to fatigue compared to other frame materials. Carbon is also quite good at absorbing vibration, aluminium generally is not. Also an aluminium frame will never compare on weight with carbon for frames of a similar strength/stiffness/ fatigue resistance.
    I'm surprised they have chosen to butt rather than hydroform the frame as hydro forming generally allows greater flexibility in design however more expensive especially for short production runs.
    However saying this I have an older BMC as my training bike. Fun to ride but one of the most rigid feeling bikes I have ridden, the back end skips around like nothing else when sprinting but that just adds to its charm.

    Can't agree with that, the CAAD10 and Canyon Ultimate AL are lighter than many carbon frames and outperform them.
    2013 Canyon Ultimate AL 7.0
    2003 Specialized Allez Sport
  • ellj22ellj22 Posts: 122
    Yes but in 10 years of hard riding under a heavy and powerful rider without either being crashed I would be surprised if the Ali frames showed no signs of fatigue whereas with the carbon bike this is less of an issue. A d yes they are very light but the supersix Evo and ultimate slx are lighter. As for ride feel, that's a personal thing. I'm not anti aluminium I'm just stating some limitations. I could do the same for carbon but we would be here all day. Also there is a lot more than just material that effect a bikes character and overall mass. Yes these are generalisations.
  • ct8282 wrote:
    So assuming you had the money, and were looking for a bike to ride distance comfortably, why would you not buy this bike....

    http://www.evanscycles.com/products/bmc ... e-ec043706

    I guess my mine line of enquiry is in relation to the carbon v Alu discussion. I realise most people would automatically expect you to buy a carbon frame when you're into big bucks, but why? We hear this word compliance a lot but what exactly does it mean when it comes to really riding a bike? BMC claim this frame is very compliant and the geometry will swallow road bumps and vibrations as good as a carbon frame. Will it really?

    So, why would you not buy this bike if you have £3600 to spend? Just because its Alu?

    I'm sure you posted this just for a bit of a debate, but if you were serious, my reason for not buying it would be because I don't like the look of it, I'm not keen on SRAM and most importantly there would be other bikes on my shopping list.
  • ct8282ct8282 Posts: 414
    ellj22 wrote:
    Longevity could be an issue, they have butted the tubes in a way to allow vertical deflection. Aluminium alloys are not usually great when it comes to fatigue compared to other frame materials. Carbon is also quite good at absorbing vibration, aluminium generally is not. Also an aluminium frame will never compare on weight with carbon for frames of a similar strength/stiffness/ fatigue resistance.
    I'm surprised they have chosen to butt rather than hydroform the frame as hydro forming generally allows greater flexibility in design however more expensive especially for short production runs.
    However saying this I have an older BMC as my training bike. Fun to ride but one of the most rigid feeling bikes I have ridden, the back end skips around like nothing else when sprinting but that just adds to its charm.

    Ali will never compare in weight??? This bike s 6.9kg....
  • ct8282ct8282 Posts: 414
    TimBooth wrote:
    The fact that you even phrase the question that way says something, does it not? Would you pose the same negative-default question about NOT buying a carbon-framed bike - if not, why? Ignore what BMC and Evans say - they're trying to sell it! Aluminium is a poor choice compared to modern carbon frames.

    Why is Alu a poor choice?
  • xixangxixang Posts: 235
    why would I not buy? because it's not campagnolo ;)
  • ellj22ellj22 Posts: 122
    Yea it's light but the components will factor into this. Look at frame weights and there are very few Ali frames sub 1200g, however quite a few companies now produce carbon frames around 800g. Personally I would be concerned to ride an aluminium bike at 800g. If your wondering why then read up on weld strength of aluminium alloys due to the HAZ and that effect on its fatigue resistance.
  • No SweatNo Sweat Posts: 103
    Rolf F wrote:
    No reason why Ti or 953 would last longer than cf.

    Try scratching your composite widget and then see how long it lasts........
  • ct8282ct8282 Posts: 414
    ellj22 wrote:
    Yea it's light but the components will factor into this. Look at frame weights and there are very few Ali frames sub 1200g, however quite a few companies now produce carbon frames around 800g. Personally I would be concerned to ride an aluminium bike at 800g. If your wondering why then read up on weld strength of aluminium alloys due to the HAZ and that effect on its fatigue resistance.

    Now this is interesting. I will look at that, thanks. So BMC market the Granfondo range as a bike designed for the punishing cobblestones of Paris Roubaix. Their teams are using these bikes for those types of races. Surely that type of surface will put an awful lot of stress on the frame. And is it important to have a frame under 1200g?
    This one weighs 1100g by the way.
  • deswellerdesweller Posts: 5,175
    Rolf F wrote:
    No Sweat wrote:
    With that sort of money you could buy something beautiful, and which would probably last longer, made from 953 or titanium......

    No reason why Ti or 953 would last longer than cf.

    I can't help feeling that a well made stainless steel frame will be vastly superior in fatigue compared to a CFRP design. I wouldn't expect a CFRP frame to last longer than a decade or so of frequent riding without developing a significant amount of compliance as the epoxy separates from the fibres; anything more than that would be a bonus. But you wouldn't be surprised by a steel frame surviving with basically unchanged characteristics for the next 50 years.

    Ti is so difficult to work with that it is very difficult to be sure that you're getting someone who knows what they're doing.

    Having said all that, at the OP's budget I would have dismissed off-the-peg frames from the off.
    - - - - - - - - - -
    On Strava.{/url}
  • rolf_frolf_f Posts: 16,015
    edited June 2013
    No Sweat wrote:
    Rolf F wrote:
    No reason why Ti or 953 would last longer than cf.

    Try scratching your composite widget and then see how long it lasts........

    Why would I scratch it? Not that it would worry me if it did.

    My Ribble is on 11,000 miles so far and doing fine; it looks like new. It won't fatigue fail. Ti welds can crack. More faith in the 953 (all my road bikes are steel or CF - I do love steel bikes though Ti frames just don't interest me at all somehow) but even steel can be damaged by a hard pothole hit and I reckon CF is probably cheaper to repair when it does get damaged.

    On what basis do you think CF won't last as long as Ti or 953? Do some research :wink:
    DesWeller wrote:
    I can't help feeling that a well made stainless steel frame will be vastly superior in fatigue compared to a CFRP design. I wouldn't expect a CFRP frame to last longer than a decade or so of frequent riding without developing a significant amount of compliance as the epoxy separates from the fibres; anything more than that would be a bonus. But you wouldn't be surprised by a steel frame surviving with basically unchanged characteristics for the next 50 years.

    Ti is so difficult to work with that it is very difficult to be sure that you're getting someone who knows what they're doing.

    Having said all that, at the OP's budget I would have dismissed off-the-peg frames from the off.

    Now this on the other hand is an informed argument! Still, what does a decade of frequent riding mean in miles? How long should I expect my Ribble to last given the mileage I do? Time is really not a very ideal measure given how different peoples mileages are. And I've not yet noticed any posts on here about people complaining about CF frames deteriorating which does imply that either we haven't yet reached the point when that becomes an issue (ie you need more like 25 years to get a problem) or that people simply don't ride frames long enough for it to be an issue even if they like the idea of a frame lasting forever. Once something becomes a bit of an antique, people don't tend to use them on a daily basis anyway at which point their life span probably becomes infinite.

    Kudos to BMC for apparently making an alloy frame match a CF one. The only question is - what actually is the point? The blurb seems to just say it is as good as CF but without mentioning in anyway how it is better. Given that the longevity of the frame must be somewhat uncertain under the circumstances, why would anyone buy this unless scared of cf?
    Faster than a tent.......
  • ellj22ellj22 Posts: 122
    Fatigue isn't much of an issue for one race though is it? I'm sure this bike is up to the job and I'm sure it's very durable. In general however aluminium does suffer with fatigue worse than other frame materials. Modern alloys are better but still not as good. With carbon a lot depends on design and lay up therefore they are very hard to compare in general. However I'm assuming both frames are produced to an equally high quality level. I'm just stating that from personal experiences aluminium fatigue can be an issue that wouldn't be a concern in other materials. Yes there are drawbacks to all materials. I have done a small amount of failure investigation ( not in bikes) and I have seen a fair few aluminium frames fail through fatigue at welds, most carbon frames through impact damage, high quality steel frames through crumpling and ti through poor weld quality. Not saying this is the only types of failure I've seen but the most common in my experience.
    Only reason I posted was to help op make a more informed decision on a bike by stating a couple potential flaws.

    If there were no drawbacks to aluminium then why has a lot of the high end industry gone carbon?
  • rolf_frolf_f Posts: 16,015
    ellj22 wrote:
    If there were no drawbacks to aluminium then why has a lot of the high end industry gone carbon?

    The interesting question is how much does this BMC frame cost to manufacture compared to a CF one. I can't see any reason why any monocoque carbon frame really needs to cost much based on its manufacturing cost (excepting hand made frames and oddities like the Impec) - but an alloy frame is presumably going to be more labour intensive to put together. I'd love to know what the respective profit margins are on the average high end frame compared to more run of the mill frames.
    Faster than a tent.......
  • giant_mangiant_man Posts: 6,878
    1) cos it looks boring
    2) cos it's a BMC
    3) cos it's running Sram Red
    4) it's from Evans
    5) i wouldn't spend that much on an alloy bike
  • imposter2.0imposter2.0 Posts: 11,969
    ellj22 wrote:
    If there were no drawbacks to aluminium then why has a lot of the high end industry gone carbon?

    Because the use of CF and layup techniques enables weight, performance and ride characteristics to be tuned in a way that is not possible with other materials. There are no 'inherent' drawbacks to producing in aluminium as such.
  • pkripperpkripper Posts: 652
    I think it's a lovely bike and would have one like a shot. However, I don't know whether that's the only model with that frame, but I would try and get the frame with a lower spec (with ultegra or force), and save a wedge of cash - red is nice if you have the cash to burn, but I wouldn't bother myself.
  • No SweatNo Sweat Posts: 103
    WRT a CF frame;
    Rolf F wrote:
    Why would I scratch it? Not that it would worry me if it did.

    Well I suppose you wouldn't on purpose, but small accidents do happen......and then the frame / fork / handlebar,or whatever, fails without any warning, at some point when you least need it.
    Rolf F wrote:
    It won't fatigue fail.

    Your faith in the marketing hype is touching... if misinformed.
    Rolf F wrote:
    .... but even steel can be damaged by a hard pothole hit and I reckon CF is probably cheaper to repair when it does get damaged.

    You can break anything if you try hard enough...... and good luck with repairing composites.
  • roktrokt Posts: 493
    For what it's worth....I'd go for the GF01 with Ultegra but I'd wait a few months
    until they reduce the price. It will drop a good grand. :D

    I do like being a Yorkshireman :mrgreen:
  • deswellerdesweller Posts: 5,175
    Imposter wrote:
    ellj22 wrote:
    If there were no drawbacks to aluminium then why has a lot of the high end industry gone carbon?

    Because the use of CF and layup techniques enables weight, performance and ride characteristics to be tuned in a way that is not possible with other materials. There are no 'inherent' drawbacks to producing in aluminium as such.

    Don't forget marketing! Muy importante. Cyclists are mugs for the latest and greatest - we all know this.
    - - - - - - - - - -
    On Strava.{/url}
  • rolf_frolf_f Posts: 16,015
    No Sweat wrote:
    WRT a CF frame;
    Rolf F wrote:
    Why would I scratch it? Not that it would worry me if it did.

    Well I suppose you wouldn't on purpose, but small accidents do happen......and then the frame / fork / handlebar,or whatever, fails without any warning, at some point when you least need it.
    Rolf F wrote:
    It won't fatigue fail.

    Your faith in the marketing hype is touching... if misinformed.
    Rolf F wrote:
    .... but even steel can be damaged by a hard pothole hit and I reckon CF is probably cheaper to repair when it does get damaged.

    You can break anything if you try hard enough...... and good luck with repairing composites.

    There's more evidence around the net of successful repair of accident damaged composites than there is of them failing through general ageing. But who knows - maybe I'm wrong. Point me to some examples of carbon frames that have had to be scrapped due to ageing rather than accident damage and maybe I'll have to reconsider my views a bit. And also point me to evidence of frames that have failed due to being scratched. Clearly you believe strongly that this is a serious issue so I daresay you have specific evidence that has given you that opinion.

    Even if you are sceptical about the repairability of cf, it definitely can be done (even at home) which is more than can be said realistically for alloy. That alloy BMC frame is an expensive and delicate investment.

    As for marketing hype - I never really pay any attention to marketing hype. Neither do I suffer from carbon fibre phobia. :wink:
    Faster than a tent.......
  • DruidorDruidor Posts: 230
    Au frame for £3600, blimy what a p take.

    its not like its of a stand out design, looks like the next Au you see down the road.
    ---
    Sensa Trentino SL Custom 2013 - 105 Compact - Aksium Race
  • copper585copper585 Posts: 141
    Get the carbon gf01 with electronic shifting for an extra 400 quid! Bit of a no brainer imho. I nearly bought the 01 when it came out but wife then decided she wanted a new house so that was that! I saw the 02 in Evans and wasn't impressed for how much they where asking. I am hanging on to see if they reduce the 01 later in year.
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