Alu Bike Still Ridable with Hairline Crack?

Tim76

Hi all,

I discovered a few hair line cracks on my road bike frame this evening when giving it a clean.

There are 3 cracks/scratches where the top tube meets the seat tube. Two are located on the side of the seat tube and look more like scratches. The biggest one is located along the top weld between both tubes.

The bike is 5 years old and there is about 6000k on the clock. It has never been crashed but has fallen over maybe twice, once with me clipped in in the middle of town. So I’m at a loss as to why these cracks have appeared.

I’m just wondering if this is normal for an aluminium frame of this age and if the bike is still safe to ride?

I’ll be taking it to the bike shop once they open again but in the meantime any advice is appreciated.

PS - will post some pics once the wife gets off the laptop!

magicbastarder

would need to see the photos, but is there any obvious flex in the frame which causes the cracks to open more?
i'd be surprised if it's not just paint cracks.

Tim76

magicbastarder wrote: »

is there any obvious flex in the frame which causes the cracks to open more?

Cheers for the feedback. No obvious flex that creates a difference. Again, they are very fine so difficult to notice anything. Will put up some pics... once i figure out how

Tim76

Ok, here are a few with the flash on - which actually makes them look a lot worse

https://imgur.com/a/pBz5Uvt

https://imgur.com/a/G2y7xzg

https://imgur.com/a/8d0tT60

https://imgur.com/a/34AtTGi

Cee-Jay-Cee

Tim76 wrote: »

Ok, here are a few with the flash on - which actually makes them look a lot worse

https://imgur.com/a/pBz5Uvt

https://imgur.com/a/G2y7xzg

https://imgur.com/a/8d0tT60

https://imgur.com/a/34AtTGi

Very difficult to tell if they simply scratches in the paint work or cracks in the alloy.

To be sure I would remove the front and rear wheels, Sit on a chair and put your foot to the seat tube and grab the top bar and pull and see if the cracks widen. If they don’t then it’s most likely just cracks in the paint work. If they do then bin them frame as it’s toast.

magicbastarder

that certainly does not look good. can you take the seatpost out and shine a torch down the seat tube? if you've any light leaks where the cracks are, the frame is toast.
note that if you *don't* have light leaks, it does not mean it's safe.

Tim76

Sound for the advice guys, I'll check out what ye said and report back. In the meantime, here are a few pics without the flash which give a better idea of the situation in natural light...

https://imgur.com/xFyCCzF

https://imgur.com/fEI1F4i

https://imgur.com/SXEKvdB

I'd be airing on the side of caution looking at those. Like you say the flash ones might make it look worse than they are but the one going across the top between the top tube and seat tube where they meet at the weld is enough to give me pause. Would normal flex in the frame do that?

magicbastarder

i was wondering if the saddle was too high/seatpost too short. it could create excess leverage in the seat tube.

AngryHippie

Aluminium is not a ductile metal, meaning it fatigues over time more significantly than steel. There is a possibility that the crack along the weld is the material starting to fatigue. Where the crack is will be the thinnest metal section (Where the metal transitions from metal+weld back to just the tube) so there will be a natural stress concentration there. I would be keeping a very close eye on that over the next few ride or two. If that crack gets any bigger (longer) or opens (wider at all), then your frame is cactus.

You could get it re-welded, but it will probably be the price of a new frame.

at1withmyself

You could gently sand down the paint and if the crack disappeared then you know its the paint. You could just touch up the paint afterwards or use a clear lacquer to protect it.

Tim76

magicbastarder wrote: »

i was wondering if the saddle was too high/seatpost too short. it could create excess leverage in the seat tube.

There is about 17cm of the seatpost outside of the frame, prob about 14cm internally but definitely less. It's a Giant Defy so given the geometry of the bike, a good bit of seatpost ends up being exposed. It's certainly within manufacturer's recommendations.

magicbastarder

yeah, that doesn't sound like it should have been a problem.

Tim76

magicbastarder wrote: »

that certainly does not look good. can you take the seatpost out and shine a torch down the seat tube? if you've any light leaks where the cracks are, the frame is toast.
note that if you *don't* have light leaks, it does not mean it's safe.

Tried out the light test but there didn't seem to be any light leaks visible. As you mention though, doesn't mean it's safe.

magicbastarder

no sign of the cracks on the sides being visible on the inside of the tubes?

Tim76

AngryHippie wrote: »

I would be keeping a very close eye on that over the next few ride or two. If that crack gets any bigger (longer) or opens (wider at all), then your frame is cactus.

You could get it re-welded, but it will probably be the price of a new frame.

Might take it for a couple of flat handy spins and see if there is any development. Given the 5k radius I won't be able to tackle any hills anyway. The last thing I want is a bit of "development" while doing 60k on a downhill.

I was reading about re-welding online last night and yeah, the general consensus was that you would be better off with a new frame.

I also came across Giant's bike warranty which said that their frames are covered for life so there might be some hope there.

Tim76

magicbastarder wrote: »

no sign of the cracks on the sides being visible on the inside of the tubes?

Not 100% on that one. I thought I saw a couple of lines internally in the area of the external cracks but they didn't seem to correspond fully with the position of them.

That said it was late and I think I may have been hallucinating slightly from all the stress/paint cracks I had been looking at on Google images

condor69

Tim76 wrote: »

Might take it for a couple of flat handy spins and see if there is any development. Given the 5k radius I won't be able to tackle any hills anyway. The last thing I want is a bit of "development" while doing 60k on a downhill.

I was reading about re-welding online last night and yeah, the general consensus was that you would be better off with a new frame.

I also came across Giant's bike warranty which said that their frames are covered for life so there might be some hope there.

As soon as I saw the title I knew it was a Giant. I've sent back two Giant Defys in the last 18 months with this exact issue. The bike shop, Hollingsworth Kilmacud, took it off me with no questions asked, sent it back to Giant who replaced the frame for free. I had to pay for the rebuilding of the bike the first time, not the second time. You will get an equal or better frame, no option on colour though.

Tim76

condor69 wrote: »

As soon as I saw the title I knew it was a Giant. I've sent back two Giant Defys in the last 18 months with this exact issue. The bike shop, Hollingsworth Kilmacud, took it off me with no questions asked, sent it back to Giant who replaced the frame for free. I had to pay for the rebuilding of the bike the first time, not the second time. You will get an equal or better frame, no option on colour though.

That sounds promising. There's an Ultegra groupset on the bike that I definitely want to salvage.

What kind of ballpark would you be looking at to rebuild the bike?

condor69

Tim76 wrote: »

That sounds promising. There's an Ultegra groupset on the bike that I definitely want to salvage.

What kind of ballpark would you be looking at to rebuild the bike?

It's 5 years old, so the warrantee will only cover a replacement frame, not the strip/rebuild.
Once you get the go ahead from the shop to send it back to Giant, ask them for a quote to strip and rebuild the bike. I striped the bike myself to save a few bob and also for a bit of maintainance practice. The only thing i gave the shop was the bare frame and forks. I think the rebuild was under €100, that included new BB and replacing all the cables.

Tim76

The bike shop where I bought the bike was actually open, albeit with the shutters down.

I dropped it into them just now and the mechanic is going to upload pics to Giant and take it from there. His initial feedback was that the frame would need to be replaced.

I asked if the strip/rebuild cost would be included under the warranty and he said that it would depend on the agreement between Giant and the owner but I would imagine I'll be taking a hit there.

He mentioned that the frame colour is a lottery as well but thankfully I'm not one of those guys who coordinates his gear with his bike

Now we play the waiting game.

Cee-Jay-Cee

Tear down and rebuild shouldn't be more than €100-150 so its costly enough but you will have a brand new frame so that's the trade off.

Tim76

Finally got the bike back there. Giant replaced the frame and fork under the warranty so now I got a brand new, squeaky clean 2019 white Contend SL frameset instead of my old Defy 0 one.

I had to pay for new cables and labour which came to €100 but I'll take that.

Now I really need to clean my old white bar tape...

Consey

Well done to Condor and the others for thr top advice!

hesker

Great outcome and great service from Giant.

seamus

While frames in general do have a limited life, I image 99.9% of bikes sold never end up being used enough to fatigue in this way. So manufacturers like Giant see the cost of replacing a couple of frames per year as pennies compared to the potential publicity (or lawsuit!) of a failed frame killing or seriously injuring someone.

Like Garmin's returns policies, I think most people would be happy to pay a nominal fee, say €100, to get a damaged frame replaced with a brand new one. So fair play to Giant on this policy, they don't have to do this, and I've never heard of anyone having issues with it.

Tim76

Consey wrote: »

Well done to Condor and the others for thr top advice!

Agreed, thanks to all for your valuable feedback. I could easily have ended up just dumping the frame or worse, ridden the thing to failure.

Chiparus

There was a problem with my mountain bike , that I did not know about - anyway the frame cracked at the seat tube/top tube junction ( Commencal meta) .
Went to aluminium welders who fixed it for €80 - that was 3 years ago- no problems since.

crosstownk

Great outcome and kudos to Giant.

I must check my Giant Defy frame for similar cracks. I've replaced wheels, cables, mechs, etc over the past 4 years so I could do with a new frame.

The bike is a bit like Triggers broom at this stage.

https://www.youtube.com/watch?v=BUl6PooveJE

retalivity

I keep reading the title as "Are u still ridable with hair in crack"