Cracked Prince Albert :(

Discovered a crack in my Prince Albert…in the drive side chainstay:

Not sure how / why it’s on the top if the stay though – comments / sympathy greatly received 😥

Lay off the pies.?

I’d have to be necking a lot of pies to crack a steel frame through weight alone 😯

which version is it?

Never seen one crack before. A friend of mine had one for a wee while and lets just say he was familiar with the pie. 😯 That poor thing took some stick.

Is it under warranty.?

No unfortunately not – it’s about three years old (is that a MKII maybe ?). Mike at Dialled has kindly offered a replacement at trade price – I’m wondering whether a mate and his welder might suffice.

What’s trade price.?

Very good – £180 (with the frame returned). I’m just too skint this month 🙁

I had worse than that on a Mk1 Soul. My local welder did it for nothing and it’s still going strong after 18 mths.

That’s reassuring – cheers BigJohn. I’ve not snapped a frame since I trashed my Tomahawk back in 1979 🙂

To quote junior Kimbrough………. That’s bad, man!

My condolances…

I had a full week of mourning when my Mk1 went to the big shed in the sky.

The PA. A true prince among bikes.

Cheers chaps – I’ve no mechanical engineering experience but I would have logically thought the stresses would have been in the other direction…as in…your weight is coming down onto the pedals / bottom bracket, and let’s say the weld between your BB and chainstay went, wouldn’t the two come apart ‘towards the ground’ (does that make sense ? sorry…bad explanation).

It also stresses upwards as the rotation of the wheel tries to drive the rear triangle upwards at the seat post. A small plate and weld should provide enough strength.

what size is it? As I have a Mk1 frame that I am thinking of selling and if you are near Bristol and want to collect we could do a deal.

I’ve no mechanical engineering experience but I would have logically thought the stresses would have been in the other direction…as in…your weight is coming down onto the pedals / bottom bracket, and let’s say the weld between your BB and chainstay went, wouldn’t the two come apart ‘towards the ground’ (does that make sense ? sorry…bad explanation).

You’re ignoring the main force that goes through that area.

the rotation of the wheel tries to drive the rear triangle upwards at the seat post. A small plate and weld should provide enough strength.

Huh?

I have a Mk1 frame that I am thinking of selling and if you are near Bristol

thanks for the offer richc but I’m up north (Cumbria).

You’re ignoring the main force that goes through that area.

Thanks Brant – can you give me a idea of the force(s)…and wouldn’t a weld be more prone to weakness than the tube itself ?

can you give me a idea of the force(s)

The fact it’s the driveside chainstay is a clue.

Ah okay…it’s breaking inwards, towards the wheel.

Ah okay…it’s breaking inwards, towards the wheel.

OK – Why is it doing that?

Pretty sure I’ve got a Solidworks, FEA analysis image of this, just not on this machine, will try and find the zip disc ( 😕 ) with this on later and post it.

You need a three finger bridge 😉

OK – Why is it doing that?

I guess you’ve got the chain trying to pull the drive side of the wheel towards the front of the bike, with the chain and seat stays there to brace against that.

Well, you’re close.

What you’ve got is a cyclic compressive and bending load.
Cyclic with pedalling force.

Got any nice pictures of this brant?, can’t find my disc with the stuff on.

Fully detailed here

Solidworks my arse.

It was 7 years ago and (uni dissertation) hence the disc is hidden in the attic somewhere, only system the place had at the time 😉

Just though an FEA test picture would help explain what your saying.

Just wanted to conclude the thread with a big thank you (and highly recommended) to Mike at Dialled Bikes for the excellent customer service in organising a crash replacement for my broken Prince Albert.

The new frame has arrived 😀

not wanting to split hairs – but – putting ya prince albert in cracks is always gonna end in tears if its not bin lubed proppa

Result!

Great service as always rom Dialled

Have also been hugely impressed with the way Mike deals with his customers. He just helped me out with great deal on a replacement Alpine after I managed to damage it (no fault of the frame I might add). Hope to keep riding an Alpine for years to come.