Why can't a child bike seat be mounted on a carbon frame?












19















I have bought a BoBike junior bike seat for the rear of my bike which is a Cargo bike but the seat instruction says it can’t be mounted on carbon frames, baffles me as to why?










share|improve this question




















  • 3





    That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

    – Gabriel C.
    Feb 11 at 14:43








  • 1





    Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

    – Criggie
    Feb 12 at 8:44






  • 3





    @Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

    – David Richerby
    Feb 12 at 15:45
















19















I have bought a BoBike junior bike seat for the rear of my bike which is a Cargo bike but the seat instruction says it can’t be mounted on carbon frames, baffles me as to why?










share|improve this question




















  • 3





    That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

    – Gabriel C.
    Feb 11 at 14:43








  • 1





    Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

    – Criggie
    Feb 12 at 8:44






  • 3





    @Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

    – David Richerby
    Feb 12 at 15:45














19












19








19








I have bought a BoBike junior bike seat for the rear of my bike which is a Cargo bike but the seat instruction says it can’t be mounted on carbon frames, baffles me as to why?










share|improve this question
















I have bought a BoBike junior bike seat for the rear of my bike which is a Cargo bike but the seat instruction says it can’t be mounted on carbon frames, baffles me as to why?







carbon child-seat






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Feb 11 at 13:39









David Richerby

12.6k33463




12.6k33463










asked Feb 11 at 11:50









ChrisChris

9613




9613








  • 3





    That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

    – Gabriel C.
    Feb 11 at 14:43








  • 1





    Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

    – Criggie
    Feb 12 at 8:44






  • 3





    @Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

    – David Richerby
    Feb 12 at 15:45














  • 3





    That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

    – Gabriel C.
    Feb 11 at 14:43








  • 1





    Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

    – Criggie
    Feb 12 at 8:44






  • 3





    @Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

    – David Richerby
    Feb 12 at 15:45








3




3





That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

– Gabriel C.
Feb 11 at 14:43







That's a pretty wide-ranging blanket statement, but I understand where they're coming from. Some particularly beefy carbon fiber seatstays might be strong enough for a child seat, but overbuilt carbon frames are the exception rather than the norm as the target customer wants light and just strong enough for a rider, not sturdy with cargo capacity. I can imagine some lightweight aluminium frames not being able to withstand child seats too.

– Gabriel C.
Feb 11 at 14:43






1




1





Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

– Criggie
Feb 12 at 8:44





Just clarifying - Your cargo bike is a carbon fibre frame ? I'd not heard of such a thing, but yes they do exist.

– Criggie
Feb 12 at 8:44




3




3





@Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

– David Richerby
Feb 12 at 15:45





@Criggie I'd assumed that the asker's bike isn't carbon but they're asking just out of curiosity, after seeing the restriction in the instructions.

– David Richerby
Feb 12 at 15:45










1 Answer
1






active

oldest

votes


















35














Carbon tubes tend to be very strong at withstanding forces in the direction they are designed for, but weak at resisting other forces (such as clamping forces compressing the tube), hence why bolts for carbon bars, seat posts etc are usually only torqued to 4-5Nm.






share|improve this answer



















  • 2





    and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

    – Chris H
    Feb 11 at 15:23











Your Answer








StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "126"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fbicycles.stackexchange.com%2fquestions%2f59296%2fwhy-cant-a-child-bike-seat-be-mounted-on-a-carbon-frame%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









35














Carbon tubes tend to be very strong at withstanding forces in the direction they are designed for, but weak at resisting other forces (such as clamping forces compressing the tube), hence why bolts for carbon bars, seat posts etc are usually only torqued to 4-5Nm.






share|improve this answer



















  • 2





    and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

    – Chris H
    Feb 11 at 15:23
















35














Carbon tubes tend to be very strong at withstanding forces in the direction they are designed for, but weak at resisting other forces (such as clamping forces compressing the tube), hence why bolts for carbon bars, seat posts etc are usually only torqued to 4-5Nm.






share|improve this answer



















  • 2





    and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

    – Chris H
    Feb 11 at 15:23














35












35








35







Carbon tubes tend to be very strong at withstanding forces in the direction they are designed for, but weak at resisting other forces (such as clamping forces compressing the tube), hence why bolts for carbon bars, seat posts etc are usually only torqued to 4-5Nm.






share|improve this answer













Carbon tubes tend to be very strong at withstanding forces in the direction they are designed for, but weak at resisting other forces (such as clamping forces compressing the tube), hence why bolts for carbon bars, seat posts etc are usually only torqued to 4-5Nm.







share|improve this answer












share|improve this answer



share|improve this answer










answered Feb 11 at 13:07









Andy PAndy P

4,215917




4,215917








  • 2





    and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

    – Chris H
    Feb 11 at 15:23














  • 2





    and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

    – Chris H
    Feb 11 at 15:23








2




2





and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

– Chris H
Feb 11 at 15:23





and that seat (I've got one on my Al hybrid) clamps onto the seat tube and seatstays. The latter clamps in particular need to be quite tight

– Chris H
Feb 11 at 15:23


















draft saved

draft discarded




















































Thanks for contributing an answer to Bicycles Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fbicycles.stackexchange.com%2fquestions%2f59296%2fwhy-cant-a-child-bike-seat-be-mounted-on-a-carbon-frame%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Aardman Animations

Are they similar matrix

“minimization” problem in Euclidean space related to orthonormal basis