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  • This topic has 43 replies, 20 voices, and was last updated 1 week ago by weeksy.
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  • carbon frame/headset sleeve issue… WTF do i even begin to do here.
  • weeksy
    Full Member

    So today as some may have seen i bought new forks for one of the DH bikes.

    2019 GT Fury. It’s a carbon frame.

    To fit the 29er setup you need to fit different cups, the reason being that the frame has a lower cup of about 22mm which raises the front end for 27.5 setup
    [url=https://flic.kr/p/2ocSo4o]2023-01-22_05-58-37[/url] by Steve Weeks, on Flickr

    So you knock out the headset cup and fit what’s essentially a zero stack one.

    However, this is where it all went wrong on this frame.

    The inner sleeve also came out… Well i say also, the cup is and was completely seized in there. Lets just say, i’ve made a proper pigs ear of trying to remove them from eachother. So the hole in the bottom of frame is shaped slightly to match the flats on the sleeve and i presume it was bonded in some way into the frame. However, clearly it’s no longer bonded. When trying to remove the sleeve from the cup, the sleeve is no longer round. It’s not damaged apart from it’s roundness… but lets say it’s not perfect. I’m not even sure if it can be made perfect again.

    [url=https://flic.kr/p/2ode3H1]2023-01-24_05-03-13[/url] by Steve Weeks, on Flickr

    Now, as to ‘why’ heck i have no idea.. It’s not impossible it was seized, it’s not impossible that the boy hitting the floor and snapping his forks completely spannered the frame at the time but only a tiny bit, enough though that when removing the cups, it’s now borked.

    So where do we go from here… if anywhere… Heck you tell me guys… because i’m right out of ideas.

    duncancallum
    Full Member

    The indent looks deliberate.

    You could try speaking to someone like target composites.

    If the carbons fine and the inserts fine bond it back in?

    The damage where is it? Have you flowered the lip over?

    joebristol
    Full Member

    Ouch – that’s annoying. Is this the purple frame then?

    I’d probably consult with a carbon repair company for them to check the headtube and see if they’ll bond the metal sleeve back in.

    No idea how you’re getting the cup and sleeve apart first though.

    frogstomp
    Full Member

    Is it definitely not all part of the lower cup? The flat bit looks a detent to ensure the alignment for the different offset (i.e so the top and bottom cups are aligned).

    noeffsgiven
    Free Member

    At least Ian isn’t involved.😀

    julians
    Free Member

    Bond it back in. I had similar with an ibis mojo hd, the sleeve came out from the frame,I just aralidted it back in and it was fine for years.

    weeksy
    Full Member

    So finally with brute force and effort i got the sleeve and cup apart… there’s a couple of tiny tiny marks on the sleeve, but with a bit of sandpaper and a gentle tiny file I got them smooth enough.

    I then did a test fit, but it was slightly out of round… However, not a lot and was easy to get back again into the right shape. we’re talking 0.1mm on the digital calipers.

    Looking at the sleeve it’s not bonded, there’s no sign of any glue of any description on it. The surface on the frame is completely smooth and no discolouration to imply it’s got any glue on it either. The sleeve slots in with a press, but it’s a tight tight fit.. .tight enough to convince me that it’s not going anywhere..

    It fits flush and nice all the way around.

    Whilst i can’t say i’m 100% happy… i’m a lot happier than i was with it a few hours ago that’s for sure.

    [url=https://flic.kr/p/2odeAEV]2023-01-24_08-29-36[/url] by Steve Weeks, on Flickr

    [url=https://flic.kr/p/2odc1iJ]2023-01-24_08-29-31[/url] by Steve Weeks, on Flickr

    [url=https://flic.kr/p/2odeAAX]2023-01-24_08-29-25[/url] by Steve Weeks, on Flickr

    I’m going to speak to a couple of carbon companies to get some thoughts tomorrow… but to be honest, i’d ride it lol.

    I wonder if we’ll need it Epoxying… I don’t mind persuading it back out again though if you think it’s for the best. The flats are on the frame too, which i guess stops any rotational movement, it’s got a lip on the inside, so it can’t go ‘up’ there’s only the possibility it could come ‘out’ but if you’d seen how tight a fit it was, i’m not convinced that’s happening at all.

    BearBack
    Free Member

    Looks like multiple stress/cracks around the head tube which is likely why the sleeve was debonded and no longer interference fit.
    Is this the frame ’08 got ejected out the front on?
    I’d say it’s borked.

    weeksy
    Full Member

    Looks like multiple stress/cracks around the head tube which is likely why the sleeve was debonded and no longer interference fit.
    Is this the frame ’08 got ejected out the front on?

    Can’t see anything in person. I’ll get a better camera on it tomorrow.

    Yes, the frame he snapped the forks one, so yes I agree it’s far from impossible that him exploding into the floor caused an issue. However, let’s not tell him that hey. I’ll take the blame for removing it, he’s small and doesn’t need to think he’s snapped his forks AND his frame. The lad would be in bits

    I’d say it’s borked.

    Maybe sir, maybe.

    dangeourbrain
    Full Member

    I’d ride it but if I were you I’d replace the frame – not because of the headset but because it must be at least a week since you bought a new one anyhow.

    I’d be tempted to epoxy it, just because it sounds like the right thing to do but not suggesting that it is, difficulty would be getting it to cure at this time of year as its bloody cold.

    spooky_b329
    Full Member

    Difficult? It just becomes a kitchen job!

    weeksy
    Full Member

    Lol I bought a bike on Sat night.

    julians
    Free Member

    The bonding is not structural, as when the forks are fitted the the frame, the fork crown and the stem keep the whole thing together, the bonding is only to stop the sleeve coming out when you swap headset cups, and possibly take out any play if the sleeve was a loose fit (which it’s not)

    weeksy
    Full Member

    Thank you

    dangeourbrain
    Full Member

    Difficult? It just becomes a kitchen job!

    Nowhere in my house is over 20 degrees at this time of year and certainly not for a 72+ hrs. Heck I wouldn’t turn the oven up past 30° if the Mrs wasn’t so picky about the colour of chicken.

    Lol I bought a bike on Sat night.

    Ah, in which case the purple one is fine 😂

    tpbiker
    Free Member

    If you’d bought a giant they would have warrantied that I expect, you’ll know better next time…😉

    weeksy
    Full Member

    Even with video evidence of a small crash?

    BearBack
    Free Member

    Ok, heres what I see in the pictures: (real life may be different and light may be playing tricks)

    3+ stress cracks to the rear of the lower head tube.
    2 major delamination’s/multi layer cracks to the 5 and 8 oclock positions on the head tube that show with the reinserted sleeve an opening up of both cracks and space between the sleeve and frame.
    The stress cracks in the top image indicative of the resulting deformation of the frame at this point with that rearmost part of the headtube having been deformed towards the rear of the bike.
    If the sleeve is now out of round, this would tend to suggest that the crash impact essentially ovalized the insert, stressing the carbon and causing the frame failure.

    I would guess that carbon repair would require significant material removal and a multi layer circumferential wrap around the head tube running into the downtube.

    I would say that this is not cost effective to repair for the next time ’08 blows up the front end as I’d think you’d be looking at complete explosive flames failure with just a re-epoxied insert.

    I am not a carbon repair expert.
    I have repaired several carbon bikes that both I and my kids still ride.
    I would not let my kid ride this one with a sleeve only repair.

    other opinions are available and mine is only worth what you’ve paid for it 😉

    cracks

    weeksy
    Full Member

    All perfectly fair comments… Once the sun is up and a bit of daylight, i’ll get checking closer. When the sleeve was out i did give it a good look over on the torch/lights, but obviously i can only see what i can see… I’ll also get a responsible grown up to have a look as well 😀

    If the sleeve is now out of round, this would tend to suggest that the crash impact essentially ovalized the insert, stressing the carbon and causing the frame failure.

    The sleeve was only out of round due to me compressing it in a vice to get the cup out. I don’t think it was out of round when it came out. It was round when it went back in.

    If the frame is dead, then that’s how it is, it’s far from ideal of course, but we’ll deal with that and better knowing now than in 6 months mid-season. As to what the plan would be… heck, i dunno. But happily, he’s got a spare bike lol.

    singlespeedstu
    Full Member

    Should the flat spots in the insert not line up with a flat spot on the inside of the head tube?
    Seems odd that you’ve re inserted it at a random rotation?
    I’d have thought the flats would go at 12oclock or 3.15.

    Personally from looking at the face of the head tube I’d not ride that.
    Looks like it’s been sanded down on a pavement by Sam Pilgrim.

    weeksy
    Full Member

    Should the flat spots in the insert not line up with a flat spot on the inside of the head tube?
    Seems odd that you’ve re inserted it at a random rotation?

    It’s hard to see as the flats on the frame don’t go right to the end, but yes, they’re aligned accordingly.

    Looks like it’s been sanded down on a pavement by Sam Pilgrim.

    THat’s only the paint that’s not present on the bottom.. I don’t see it as anything more than that.

    I am in the process of potentially buying a replacement frame though 🙂

    edit. Just spent the last 5 minutes in the garage.. (BRRRRR) i’m 100% happy there’s nothing untoward on the frame in terms of cracks, splits, deformations. The marks you can see are paint/lacquer only issues, I’ve not looked on frame2, but i expect they just loosely paint that bit or the paint sticks to the cups, as the cups are pressed in afterwards. But to the naked eye, it’s 100%. The carbon layup there is about 4mm thick, proper sturdy stuff…

    I’d happily ride it… and of course will do so at times lol. 😀

    singlespeedstu
    Full Member

    THat’s only the paint that’s not present on the bottom..

    If that’s how the face of the head tube is finished under the paint I’d be very surprised.

    weeksy
    Full Member

    If that’s how the face of the head tube is finished under the paint I’d be very surprised.

    I can only see what i can see… I don’t think the picture helps.. But often in close up on cameras they make things look worse. It’s completely possible that the bottom/flat of the frame is painted in the factory, but that’s chipped off as headset cups have been added/removed/replaced in the past. But as i say, i’m happy it’s nothing more than paint that’s chipped. The carbon itself, i’m happy with.

    singlespeedstu
    Full Member

    Sounds like you’re doing a good job of trying to convince yourself there.

    weeksy
    Full Member

    Not at all, i’m convinced 🙂

    bruneep
    Full Member

    At least Ian isn’t involved.😀

    Deserves praise 👏

    julians
    Free Member

    The headtube does look knackered in those images in bearbacks post, but you’re the one with access to the actual bike rather than some photos on the internet – photos can be misleading

    dovebiker
    Full Member

    This stuff should see you sorted. Best done indoors in warm temperatures rather than a chilly garage. Head tubes are massively overbuilt due to the stresses they endure – if you can’t see any physical evidence of weakness or distortion/delaminating/cracking then it’s probably OK

    steve_b77
    Free Member

    It’s not impossible it was seized, it’s not impossible that the boy hitting the floor and snapping his forks completely spannered the frame at the time but only a tiny bit, enough though that when removing the cups, it’s now borked

    You’re either incredibly brave or daft in the head to contemplating riding a carbon or any frame where the forks have snapped without getting it NDT’d by a pro.

    weeksy
    Full Member

    thanks @dovebiker

    I was chatting last night to a mate who builds and designs the Team GB carbon bikes, he was telling me the spacer is simply a press-fit even on their bikes as ‘the glue would be pretty much useless for this application’ although i didn’t ask why yet… But he does stuff for team GB, F1 teams, Touring Cars teams etc, so is pretty clued up on carbon.

    My biggest concern at the moment is the 2nd frame as ideally i need to knock the cups out of that one too when the new headset arrives… Although i did have that one out on Sunday night to check which one it was in there. It came out fine. But i must admit, i’m tempted to leave it alone, even though techincally it’s ‘incorrect’ in setup, the boy seems most happy with it.

    weeksy
    Full Member

    You’re either incredibly brave or daft in the head to contemplating riding a carbon or any frame where the forks have snapped without getting it NDT’d by a pro

    He rode it many many times after crashing. It’s not had an issue.

    IvanDobski
    Free Member

    If I was in your shoes – this would be an insurance company problem, not a me problem tbh.

    You’ve got the crash on cameras (I think?), ring your house insurance company tell them the frame and forks broke in that crash, send proof, pay excess, get payout, buy new stuff, sell old stuff as spares/repair, job done.

    I’ve done it several times, as long as you can point to a single incident being the cause of the problem and not just wear and tear etc then it’ll almost certainly be covered in my experience.

    weeksy
    Full Member

    If I was in your shoes – this would be an insurance company problem, not a me problem tbh.

    You’ve got the crash on cameras (I think?), ring your house insurance company tell them the frame and forks broke in that crash, send proof, pay excess, get payout, buy new stuff, sell old stuff as spares/repair, job done.

    I’ve done it several times, as long as you can point to a single incident being the cause of the problem and not just wear and tear etc then it’ll almost certainly be covered in my experience

    Say what now.. I can’t even imagine for a second how this is a thing. I honestly don’t even know if the insurance company would cover that, but i really can’t imagine how… Seems very wrong to me.

    singlespeedstu
    Full Member

    It’s not had an issue.yet

    robbo1234biking
    Full Member

    https://laka.co/gb/bicycle-insurance/mountain-bike-insurance

    Other insurance companies are available but you can buy cover against this stuff. Might be quite cheap compared to some of the costs that you are paying for.

    teethgrinder
    Full Member

    Barclays bike cover covers accidental damage. Paid out on my out of warranty Banshee that snapped JRA due to known issue at the DT-ST brace weld.

    julians
    Free Member

    Say what now.. I can’t even imagine for a second how this is a thing. I honestly don’t even know if the insurance company would cover that, but i really can’t imagine how… Seems very wrong to me.

    it called accidental damage cover , can be bought as an extra (or included) as part of your home insurance policy – I dont have it – because I choose not to pay extra for it.

    if you are going to go down the route of insuring against accident damage, just read the small print and check it will provide cover during competition,racing etc .

    weeksy
    Full Member

    Well it seems I do have accidental damage cover..

    You’re right that it doesn’t cover racing/competition etc…. But that wasn’t in competition, it was a day out at Rogate.

    However that does start bringing in massive levels of complexity, especially as you can’t buy new GT Furys, either as a frame or indeed a whole bike. To be honest, it’s not really a road i want to go down.

    weeksy
    Full Member

    So me and a mate have been looking… Happily we have a 2nd frame to pick any thoughts out of too, plus i needed to remove the headset cups on that one too.

    What i’ve established is…. on the GOOD frame, there’s paint beneath the spacer and potentially a bit of carbon too… on the purple frame that paint is missing. However, looking now, this is NOT new… this is old and has been removed from before when we’ve owned the bike. What it looks like has happened is that a previous owner has done this and removed the cups before, but when he’s done it he’s actually knocked out the non-removable (usually) spacer as well. You can see the chips/marks in the paint have been touched up (which you couldn’t really see when everything was fitted without VERY close inspection).

    So, removing the cup last night wasn’t the cause of any issues, it’s no worse than it was…. but admittedly it’s no better. Whilst the paint is no longer present, there’s nothing that indicates any extra additional damage to any of the carbon and it’s truly massively over-engineered around that area.

    Where does that leave us.. Well in truth, no better worse than we were before yesterday. Just with more knowledge that something has previously happened now. But i don’t think the frame is any more ‘broken’ than he’s been riding for the last 12 months lol.

    jameso
    Full Member

    But i don’t think the frame is any more ‘broken’ than he’s been riding for the last 12 months lol.

    The risk is that it looks fine now then fails catastrophically while ‘JRA’ 14 months after or something like that. I’m admittedly cautious with carbon but do think about how unseen voids (all CF frames have them to some extent) can become small delamination areas after impacts and extended use, those delamimation areas can grow until beyond what was within the margin of error of the design. Carbon can fail pretty fast when it gets to that point.

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