Cracking lug structural advice

Hello,

I got really excited today getting a look at an *actual *track frame that was my size, and that I could afford. It was my first experience of that combo in a year & half of looking!

It was labelled up as a kuwahara, but both me and the seller agreed it was probably something else rebadged.

Well just before I jump up & click my heels, I notice some rusty hairline cracks in the paint around the headtube/top tube lug. Damnit! I keep telling myself its just waterpenetration, so the seller says its ok if I strip the paint off, so I do.

After cleaning up the worst was confirmed, and im rather gutted! As I had the perfect build in my head for days. Instead of going back to square one, Im hoping it might be cheaply repairable, but I need some advice on how sturdy/reliable its likely to be now & after a bodged repair. If the job is difficult & expensive?

The seller has been riding it for ages, no brakes, no crashes. And says if I dont buy it, hell just repaint it and continue riding it.

Yes its visible damage on BOTH sides!

But I still really like it. I need to let him no by tommorow as he needs the money for a replacement bike on ebay that ends then.

Prompt advice would be appreciated on whether this is worth pursuing.

Thankyou.

very odd. it's almost as if the lug is brittle, suggesting something went wrong heat/quench wise when the lugs were made. or perhaps there is little penetration with the brazing so there's no filler metal that far under the lug. i would have thought it would go further back on the top and down tubes or on the tubes just behind the lugs.
if it were mine i wouldn't ride it.

agreed. looks like the lugs were not made well, possibly just inferior steel, or what MrSmith said.

If this were someone else would you advise them? I might ride it with a repair if I already owned it, but I certainly would never buy a frame with a structural fault.

Fuck it ride it!

the lug was probably cracked when a headset was installed, or removed the wrong way. it is not repairable. sorry.

the lug was probably cracked when a headset was installed, or removed the wrong way. it is not repairable. sorry.

why are you sry ? hehe

you could, i guess, file the both cracks out down to the top tube and TIG weld it,
then file it back down again flush. a little like having a filling at the dentist.

proper skilled job that though, and im not sure as to it's viability.

looks good i love it!

you could, i guess, file the both cracks out down to the top tube and TIG weld it,
then file it back down again flush. a little like having a filling at the dentist.

proper skilled job that though, and im not sure as to it's viability.

i wouldn't do that too much heat involved with tig compared to brazing

Those lugs are pressed steel, so it's possible that it's damage done when they were made, but no reputable builder would have used them in that state, so you can rule that out. It's more likely to be damage from a crash.
A rebuild of the front end would cost you about £200, plus a respray. It's simply not worth the money.

agreed leave it alone, a different frame will come along that will make you far happier in the long run. how much was he selling it for just out of interest?

yeah, wait for a good frame... there's no way i'd ride that bike. get your money back and keep looking.

i wouldn't do that too much heat involved with tig compared to brazing

You can tig weld to repair cracks, but in this case the structural damage is going to be underneath the lug and the tig weld won't penetrate that far. Lugs really just hold everything in place, it's the bronze in the joint that gives it the strength.

Cracking lug structural advice
I don't think this advice is all that...

but the heat involved in tig welding is a lot higher than a with a gas torch. it will melt the filler metal either side of the crack and weaken the whole joint further.
or are you suggesting to re-braze after welding? which is a bit silly as you may as well replace the lug if you are.

actually having asked my father* about this (again) he said the bronze will contaminate the weld as you can't prepare the back of the joint area properly and whoever suggested this method doesn't know what they are talking about.

*was a welding technician/demonstrator at a technical college

Cracks = trouble and an unreliable frame. Take you loss and dump it.

actually the person to ask is walkersan, he makes lugged frames.

he's probably busy sorting my new frame for shipping!

anyway, lug replacement would be the only real answer, provided the tubing isn't crappy at the ends which you wouldn't find out till you started the job.

In short, leave it alone and buy something else.

If it is costing what a cracked frame should, buy it for some trashing fun, its probably worth 10 pounds.

Otherwise a cheap frame of none descript origin, made of none descript tubing with pressed lugs should probably run you about 80-100 elsewhere.

he's probably busy sorting my new frame for shipping!.

??

Your not getting rid of the chas ?

you could, i guess, file the both cracks out down to the top tube and TIG weld it,
then file it back down again flush. a little like having a filling at the dentist.

proper skilled job that though, and im not sure as to it's viability.

never ever file a tig wield smooth the ridges are an important structural part of the weld, filing them severely weakens the weld, and will lead to it breaking.

And I echo what MrSmith said about the heat.

The only way to repair the frame would be to remove the lug, find one of simalar dimensions, re file the tubing to fit the new lug, and re-braze. that is at least 3 blast of heat if the builder is good, and a lot of stress to put on a frame that has had a hard life. Also this would only be possible if the tubing is in really good condition, and a simalar lug can be found.

all in all its not worth it.

??

Your not getting rid of the chas ?

no way!

unless I get a better offer next season

The only way to repair the frame would be to remove the lug, find one of simalar dimensions, re file the tubing to fit the new lug, and re-braze. that is at least 3 blast of heat if the builder is good, and a lot of stress to put on a frame that has had a hard life. Also this would only be possible if the tubing is in really good condition, and a simalar lug can be found.

all in all its not worth it.

just out of interest if you were to do this you would have to take of both head tube lugs and the head tube off, replace the cracked one and then re braze them on to the frame, right?

agreed leave it alone, a different frame will come along that will make you far happier in the long run. how much was he selling it for just out of interest?

It was £140 for the whole bike before I stripped the paint and revealed the damage. I didn't discuss prices after that, as I knew the seller had their heart set on that specific amount of money to buy their new bike and would be upset by the huge drop in value of a cracking frame. I just said I was hugely dissapointed, and Ill think about it.