I own this Fuij Roubaix 2008 model road bike, its an aluminium frame with carbon front and rear forks. I already did 25000km on the bike and replaced wheels, chainring, a couple of cassettes, chains and so on.

Will the frame wear out? I am only concerned that the frame will ware out and fail during riding, otherwise I like the bike since its suits me, the size is just right and I like the non-sloping frame.

I am concerned about frame because the rear bolts between the carbon seat stays and the aluminium chain stays were lose and there is this mechanic which every time it sees me with the bike says that its going to break.

What do you think? I would avoid buying another bike not because of the cost but because I like my bike and to the new one I would have to adjust a bit.

Basically I am asking how to know when to replace a bike or a bike's frame,

  • 1
    I would ask for specifics. Ask the mechanic to show where the frame is going to fail and why.
    – paparazzo
    Mar 12, 2016 at 16:42
  • I think your mechanic is trying to do a sales job on you. Consider a new mechanic. And +1 for loving the horizontal top tube .
    – Criggie
    Mar 12, 2016 at 19:20
  • 1
    I rode a road bike all aluminum, roughly 20000km, significant rough roads, some off road, 1 accident and a lot damage to peripherals other than frame. Mechanic: it might give up at wrong time, replace it. Other one said it's alright. A periphery gave up but not the frame. If frame is all aluminum try checking for fatigue, cracks, bends, dents, tearing, any one or all of them mean it's about time
    – user14633
    Mar 13, 2016 at 20:26
  • @frisbee I think he means that the frame is going to fail at the junction of carbon with aluminium between downtube and seat stays. Mar 13, 2016 at 20:31
  • @yawar I haven't seen any cracks, there is small bend in the top tube I made when leaning the bike against a wall, it just made small bent, but I doubt this has any impact on the frame integrity( you can barley spot it ) Mar 13, 2016 at 20:33

1 Answer 1


25000 km isn't a lot.

There isn't a time or mileage you should consider swapping out a frame. Instead, you should look for damage, such as dented tubes or cracks. You should be especially wary if you've been in an accident to check your bike out. Carbon fiber complicates this a bit, because its failure modes are generally more rapid than metal and harder to detect damage visually.

The mechanic might be trying to sell you something (most likely) or he might be right. You may want to get a second opinion from another mechanic.

  • 2
    +1 for the last sentence. Never discard information offered from someone more experienced than you, but equally, don't take it on face value because of this experiance.
    – mattnz
    Mar 12, 2016 at 20:10
  • Well, they guy is really good mechanic, I had my wheels aligned by him and that was great. From what I remeber he had an experience with a similar frame( aluminium + carbon ) that failed, maybe he is just biased. Will try to get a second opinion this. Mar 13, 2016 at 20:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.