Bicycle Mechanics - cracked frame

I have a great old bianchi lugged steel road bike from the 1980's, but there has been a disturbing development. It seems to have developed a hairline fracture in the bottom bracket lug, about an inch and a half horizontally (i.e. from the left crank towards the right crank, right on the bottom). What is the prognosis for my italian beauty? I know that it's unsafe to ride a cracked frame, but do you guys think I'm in imminent danger? I have a co-worker that does some welding, and I'm thinking of seeing if he'll repair it, but he knows nothing about bikes. Would he be able to accomplish this? Any guidelines I would give him? How much would I expect to pay a bike shop for the job, and is this the right solution?

Thanks

Josh

Hey Josh

I'm no expert but if it was my bike I'd talk to someone that was knowledgable about welding.
Because the makeup of the tube (ie the carbon content of the steel) used can affect the strength and durability of the weld it's important to have it done properly.

If it's a lugged frame it's brazed not welded. Welding in not compatable with all steels since it can significantly lower the stength. Your best bet is to have a framebuilder replace the BB shell. It's a simple enough job and you can get a nice new paint job as well.

Dave

Josh,

Yes it is repairable, but I would have it sent
to a reputable frame maker to do so
(I know of a few that do this kind of thing).
Agree that welding is NOT a good idea,
a framebuilder will remove the tube (its the
seatube and not the BB right?), and replace
it, repaint etc.
If its the bottom bracket shell I'm not sure.
I can ask around on that one.

Marty

is this economically advisable, no matter how much money is put into a 1980's steel bike its value doesn't change.

is this economically advisable, no matter how much money is put into a 1980's steel bike its value doesn't change.

I'm assuming you ride your bike because you realy like it, not due to its value but he does have a point. On the other hand, the cost of the repair should still be less than going out and buying a comparable frame.

If she's your baby, then I say send her off to a framemaker for the repair.

By the way, I just noticed your full username and wanted to say...

SOYLENTJOSH IS MADE OF PEOPLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

It actually is the bottom bracket shell and not the seat tube. Does anyone know what price range this kind of repair is in?

Thanks!
Josh

Originally posted by stumpjumper
By the way, I just noticed your full username and wanted to say...

SOYLENTJOSH IS MADE OF PEOPLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Only in the film. :)

Josh,

A cracked bottom bracket shell is a bit more
complicated, have to remove seat, and downtubes and
chainstays. I'm guessing it can be done.
(I've started a query with some framebuilders)
Can you post pictures?
I'm guessing it wouldn't be cheap.
What model Bianchi? Superleggera?
if anything less than Campione I'd say probably not
worth it.
I'll let you know what I hear from framebuilders.
thanks,
Marty

I think I've seen on the Mercian site a price quoted for replacement of a BB shell

I got a few responses
if I may quote

Oh, it can be done... It's just "can you stand the tariff?"
Dale Brown
cycles de ORO, Inc.

"it's do-able but would cost more than the cost of the frame."
Richard Sachs
(yah that Richard Sachs).


Marty

Mercian quote £60 for a replacement BB shell and bridge ($100)

http://www.btinternet.com/~merciancycleslimited/pages/repairs.htm

Bob Jackson do it for

New Bottom Bracket Shell(Pressed) £68.75
New Bottom Bracket Shell(Cast) £93.00

http://www.bobjacksoncycles.co.uk/repairs.htm
but you have to repaint the bike as well.

Ugh...maybe I should investigate a new frame. Too bad. I'll start looking on ebay, but does anyone know a good deal on cheap frames?

Thanks!
Josh

j b weld yoour hairline crack its not worth anymore effort than that really if the crack is in the lug ride it till ya cant ride it no more lol

Josh,

Well its interesting, I've gotten a few responses from
other framebuilders who say that the BB shell can
be Welded, so it might be worthwhile to have a builder
look at the frame.
One thing is certain is that everyone said not to do
it yourself unless you really know what you're doing.

There are some nice frames out there,
check RBR, Rec.bicycles and of course e-buy.

Marty