Cracked frame or cracked paint? Help please

[Johnsco]

As @Johnsco suggests I think a dye penetration test is the way to be 100% certain; by gut tells me the head tube will pass (for now) and the BB will fail.

Wafter --- I think you're probably correct --- The bottom bracket appears to be much more worrying.
But - You need a test to be sure.

 

[classic33]

@wafter, the joints will have been rounded, rather than straight, sharp joints to reduce the stress at these parts.

 

[avecReynolds531]

Thanks Wafter, that was informative & much appreciated.

ally "lugs" (fabricated with smoothed welds?) that have reduced diameter female bosses that are then bonded into the ID of the CFRP tube, and smoothed to give a seamless transition..?

This is my understanding of the construction of the majority of the main triangle. You can't feel the transition from aluminium to carbon in these parts of the frame.

(As an aside, a highly renowned framebuilder praised the way Pinarello had finished the frame.)

The exceptions are the wishbone seat stays and the seat tube - these carbon pieces fit within a greater diameter section of aluminium.

The aluminium has smooth welds with the exception of the area where the chain stays meet the bottom bracket - particularly the inside of the chain stay/ bb join which has the chunky (& ugly) welds that are common on alu frames.

Edited for clarity.

In a more simple sense, is it safe to assume that all of the areas where cracking is apparently visible are definitely in aluminum rather than any bonding material or CFRP wrapping?

Yes, all the cracks are in the aluminium sections (as shown in the lighter blue painted sections of the frame).

The bottom bracket appears a lot more serious, both because of its shape and more importantly the colouration. As I found out when my frame cracked you'll get a dark deposit at the crack, presumably as the exposed material is abraded by the two sides rubbing together and oxidising. Try wiping the crack with a piece of white bogroll and see if it picks up any black dust from the crack itself or the blackness of the crack seems less after wiping - if so it's almost certainly game over.

I had read the OCR cracked frame thread previously (with a lot of interest) when researching this. I've just tried running a piece of kitchen towel across the bb crack but no black dust was picked up & the crack hasn't changed colour. But I notice it's travelled further around the back of the seat tube since the last ride.

I'll retire the frame now. In the next few weeks I'll dismantle the parts, then it'll be free to anyone who could make use of it: maybe an engineering class dissection, or someone willing to take on the repairs?

With many thanks for all the input and knowledge shared

 

[wafter]

Thanks Wafter, that was informative & much appreciated.


This is my understanding of the main triangle construction. You can't feel the transition from aluminium to carbon in this part of the frame. As an aside, a highly renowned framebuilder praised the way Pinarello had finished the frame.

The exceptions are the wishbone seat stays and the seat tube - these carbon pieces fit within a greater diameter section of aluminium.

The aluminium has smooth welds with the exception of the area where the chain stays meet the bottom bracket - particularly the inside of the chain stay/ bb join which has the chunky & ugly welds that are common on alu frames.



Yes, all the cracks are in the aluminium sections (as shown in the lighter blue painted sections of the frame).



I had read the OCR cracked frame thread previously (with a lot of interest) when researching this. I've just tried running a piece of kitchen towel across the bb crack but no black dust was picked up & the crack hasn't changed colour. But I notice it's travelled further around the back of the seat tube since the last ride.

I'll retire the frame now. In the next few weeks I'll dismantle the parts, then it'll be free to anyone who could make use of it: maybe an engineering class dissection, or someone willing to take on the repairs?

With many thanks for all the input and knowledge shared

No worries - glad you found it of use / interest

Thanks for the additional info; sounds like an innovative and interesting construction - although unfortunately not immune to the mechanical shortcomings of aluminium.

It's a shame you're having to retire it but really I think that's the most sensible option; especially given your observations about the apparent crack at the BB. Unsurprisingly it appears that the worse a crack gets the faster it propagates; so if it's noticeably larger after one ride I suspect it's not far from failing completely.

 

[avecReynolds531]

although unfortunately not immune to the mechanical shortcomings of aluminium.

As a post script to this (14+ years) memorable stint with the Opera Leonardo...

from now on, a replacement frame will range from:

to

 

[classic33]

Thanks Wafter, that was informative & much appreciated.


This is my understanding of the construction of the majority of the main triangle. You can't feel the transition from aluminium to carbon in these parts of the frame.

(As an aside, a highly renowned framebuilder praised the way Pinarello had finished the frame.)

The exceptions are the wishbone seat stays and the seat tube - these carbon pieces fit within a greater diameter section of aluminium.

The aluminium has smooth welds with the exception of the area where the chain stays meet the bottom bracket - particularly the inside of the chain stay/ bb join which has the chunky (& ugly) welds that are common on alu frames.

Edited for clarity.



Yes, all the cracks are in the aluminium sections (as shown in the lighter blue painted sections of the frame).



I had read the OCR cracked frame thread previously (with a lot of interest) when researching this. I've just tried running a piece of kitchen towel across the bb crack but no black dust was picked up & the crack hasn't changed colour. But I notice it's travelled further around the back of the seat tube since the last ride.

I'll retire the frame now. In the next few weeks I'll dismantle the parts, then it'll be free to anyone who could make use of it: maybe an engineering class dissection, or someone willing to take on the repairs?

With many thanks for all the input and knowledge shared

You're not framing your frame now?

 

[Globalti]

Just to throw a spanner in the works... if part of the frame was about to break you would see cracks only there. The fact that there are cracks all over the frame tells me it's the lacquer cracking. Possibly years of exposure to UV have made it brittle.

I would give it a good push and pull and squeeze and if you don't hear creaking, carry on riding it.

 

[wafter]

As a post script to this (14+ years) memorable stint with the Opera Leonardo...

from now on, a replacement frame will range from:
View attachment 538671
to
View attachment 538672

A man after my own heart!

I've just about gone full circle now.. first road bike was a tatty steel (Reynolds something - 531?) offering I bought for £20. When I got into it this was "upgraded" to the ally Giant then years later when that failed a CFRP Boardman.. last purchase was a steel Croix De Fer (after catastrophic-failure anxiety over CFRP got the better of me) and I potentially now have a steel shopper in the form of an old rescued Raleigh.

Tbh from this point on I have no desire to own anything that doesn't have a steel frame.

Just to throw a spanner in the works... if part of the frame was about to break you would see cracks only there. The fact that there are cracks all over the frame tells me it's the lacquer cracking. Possibly years of exposure to UV have made it brittle.

I would give it a good push and pull and squeeze and if you don't hear creaking, carry on riding it.

Nice point - I'd agree about the lacquer with the exception of the situation at the bottom bracket which looks FUBAR tbh..

 

[classic33]

A man after my own heart!

I've just about gone full circle now.. first
Nice point - I'd agree about the lacquer with the exception of the situation at the bottom bracket which looks FUBAR tbh..

That looks/appears to be following a joint round, it's too uniform and no jagged edging to it.

 

[wafter]

That looks/appears to be following a joint round, it's too uniform and no jagged edging to it.

Yup, that was my thinking too. Of course both a crack in the material and lacquer area most likely to follow lines of greatest strain, but I agree this looks very different to the other areas.

 

[classic33]

Yup, that was my thinking too. Of course both a crack in the material and lacquer area most likely to follow lines of greatest strain, but I agree this looks very different to the other areas.

I had one go there, and the picture posted is very similar to what mine looked like. Frame replaced by the manufacturer as it was less than six months old when it went.

Bought a roll of tape, wrapped the bottom bracket and two main tubes, before it gave to get me home.

 

[wafter]

I had one go there, and the picture posted is very similar to what mine looked like. Frame replaced by the manufacturer as it was less than six months old when it went.

Bought a roll of tape, wrapped the bottom bracket and two main tubes, before it gave to get me home.

Crikey - a failure there within 6 months is appalling!

 

[classic33]

Crikey - a failure there within 6 months is appalling!

That's what the bike shop said, it was they who got the manufacturer to supply the new frame. More annoying than anything else.

Even gave me free loan of a bike until they were able to rebuild the bike.

Part of it, think it's the top tube, resides in the shop still. Purely to show how the tubing is butted.

Quickest frame failure, less than 90 minutes after handing over the balance owing over. Right rear dropout parted company with the tubes it was attached to.

 

[wafter]

That's what the bike shop said, it was they who got the manufacturer to supply the new frame. More annoying than anything else.

Even gave me free loan of a bike until they were able to rebuild the bike.

Part of it, think it's the top tube, resides in the shop still. Purely to show how the tubing is butted.

Quickest frame failure, less than 90 minutes after handing over the balance owing over. Right rear dropout parted company with the tubes it was attached to.

Gash - hardly breeds confidence in one's kit does it?

 

[classic33]

Gash - hardly breeds confidence in one's kit does it?

These things happen.
Two seperate bike shops, the rear dropout parting company, was from a shop the insurance chose. The seat tube/bottom bracket bike was from a shop of my choice. Both had been fair with me.