Cracks in Aluminum Frames..
 

I pretty much know, My bike is trashed . Right..? I have what appears to be a crease on the side of my top tube , on the side mid-way between the seat post and the head tube.. It's about 19 mm in length and deep enough I can insert my thumb nail into it.. I will not know for sure if its a crack or a scratch until I remove the paint.. ?.. Once it appeared as just a scratch , but now the fold appears to be deeper..?
I hate this because I have an appreciation of Klein's for historic value.. Would my love of Klein bikes be worth attempting to repair my top tube or just a total waste of money. Should what appears to be a cracked frame be a real crack.
My club members say they know of a good Tig welder at some shop... .. Even so.. ? It would still be a waste..?
Thanks..

With Aluminium, wouldn't trust it, if it had a crack in it, especially on an ultra thin walled Klein. Also, if you did get this welded, you would have to ensure that it was correctly heat treated again, whcih is hard to do.

For historic value, that really depends on the color scheme it is in, as some are much rarer than others. Could make a good wall piece!

Should it be an actual crack, when will I know if its unsafe to ride.. ?.. Likely Now..?

The issue that arises is that almost all aluminum alloy tubed frames
are heat treated after assembly (welding).

This increases considerably their overall strength, but it makes
them, for all practical purposes, unweldable. The heat of welding
resets the area around the weld and unless you can retreat the
whole frame again in some kind of annealing oven, it will give
up pretty quickly somewhere near that spot.

Even putting some kind of sleeve over that part of your tube thus
becomes impossible.

When I was a glassblower, we used large annealing ovens that might
fit a bike frame, but you still end up with painting issues and I'm not
100% sure of the heat treating temps required for your particular
tubing.......or if it early enough in history, whether it was heat treated
at all.

I wouldn't personally ride it now. You might be able to sleeve the area
with some sort of cut to measure alloy sleeve attached with a cold
process.....like epoxy. If you try this (and I would advise against it),
make sure the sleeve is pretty snug and that you have removed the paint
and roughed the surface in the area of the sleeve.

Nothing is forever, my friend.:(

You really should stop riding it immediately. With a frame that is not damaged, you can be sure that it almost definitely won't immediately snap in half and throw you under an SUV. But with a damaged frame, the risk goes up drastically.

SUV? Why not a natural gas powered bus, a hybrid, a Tesla, or a trolley passing by?

=8-)

I have not been able to deterimine a correlation between my hypothesis about SUVs and electric cars... the sample size is too small. Don't worry, though. As soon as more electric cars are on the road than SUVs, you might get run over by one of those instead.

Where are the pictures ? Are you sure it's gotten worse ? Or maybe it just bothers you more now.

Indeed. I am now the proud owner/driver of one of these:

http://upload.wikimedia.org/wikipedi...earl_White.jpg

and it is just as quiet and deadly as you all imagine it to be.:twitchy:

Be afraid........be very afraid.:p

Very cool! What is the range between charges?

That's the truth actually...there have already been reports of people getting hit by them in crosswalks - with the complaint noted afterwards by survivors that they didn't hear 'em coming. I think I've already read one report that hybrids/electrics may be required in the future to have "sound" generating devices that mimic the sound of an oncoming car for safety purposes.

Wouldn't matter for a deaf guy like me though!

:D

=8-)

I would have.......Pictures later.. I am away from home and my bikes for a couple weeks ..

Gauge says @115 miles on fully charged, now pretty much brand new batteries.
They will, like all batteries, degrade with time. Nissan warrants them for 8 or 10
years (I forget which) to take enough charge to take you 80% of that....so toward
the end of the life cycle probably 85-90 miles.

From flat discharged to full takes about 4-5 hours on a 220 charger, pretty much
overnight on a 110 circuit. Thing is, range is not the issue for a lot of us....not me
anyway. What is an issue is the little sucker goes like a bat out of hell and handles
about that well, too. Steering is very quick and the bulk of the weight (batteries)
is along the length of the floor pan, so it really holds the road.

As an only partially reformed delinquent, it requires considerable self control not
to drive a little more aggressively than might be prudent.:o

It's a genuine issue. I try to play George Thorogood and the Destroyers
or the equivalent at full volume on the stereo when I drive in town, but
like you say, anyone with hearing impairment is at considerable risk.

I think after the last few months the novelty of having a very quick,
responsive car is wearing off and I might be able to slow down somewhat.
If I actually hit a cyclist, I might as well commit Seppuku.....I will be
completely ostracized here in the Big Tomato.

Danged near got wiped by one in the parking lot at my workplace. Silent killers..... Seriously, they are SO quiet that I can understand that there would be added danger to pedestrians. "Situational Awareness" is so important as a cyclist, and these silent cars are just one more reason why.

These just move the exhaust from the tailpipe to the smoke stack of the coal fired plant.

Not that getting the emissions out of the population centers isn't benefit enough, but it's also a lot easier to fix a single scrubber to a coal plant to reduce NOX than a thousand to cars.

Plus, you are helping to create support for a new distribution system, one that can be switched over to electricity generated from cleaner options, like solar, wind, biomass or burning human flesh.

^^^^^^^^^^^^^^^^^^What he said. ^^^^^^^^^^^^^^

If you live in California, moving emissions to a central point where
they can be scrubbed is a huge step forward. You'd realize this
if you lived in the Central Valley or in L.A.

And if we ever pull our heads out of our asses here with regard
to energy conservation and use, we are ideally suited in my state
to generate electricity in cleaner and renewable ways. We have
inherited a huge hydroelectric system here, and if we were able to
use power more rationally (large if), it would go a long way.

Thats right.. and since most people with eCars would be charging the at night, the electrical stations that run all the time (like nukes) can charge batteries while the power isn't being used for anything else.

But those huge rechargeable batteries make these cars the most environmentally unfriendly cars ever produced by an order of magnitude.
Disposing of a rechargeable cell phone battery or 2 AA's is already a problem. And if you want a car that does a 100 miles (50 if it's cold out and need the heater),
and have to buy new batteries (make an new toxic waste battery pack) for $5-7000 after a few years have fun.

:love:

Given the current paradigm for automotive transportation
and its complete dependence on fossil fuels, I'm gonna
hazard a guess that you don't really believe in global warming
either?:lol:

At any rate, it would appear any further discussion here in
the mech's forum on what started out as a perfectly reasonable
"can i fix this or will it eventually hurt me" thread is a major
hijack that heads nowhere but P+R, so I'm out.

For the record, in case it's not clear enough, unless you
can sleeve the area with either some kind of mechanical clamp
or cold process epoxied sleeve reinforcement ( and you might
still want to mechanically clamp that one, until you are
certain it is truly bonded)......it might be time to recycle
the Klein.:(

I would try to have it welded. You have nothing to loose. I had the opportunity recently to use a Miller MIG Welder with an aluminum wire feed attachment and I am certain that it would provide a good repair in this case. Despite what others have stated the heating is very localized and the heat treating does not come into play for this type of repair. Just take it to a good welder, you'll be fine.

THere are many things wrong with your comments.

To the OP: please disregard brokencase's ideas. You DO have something to lose. No MIG welding of bike frames. Welding DOES affect heat treatment (even if only in an isolated area) and that could be a problem.

Help Commerce, eat your losses, Recycle the frame as Scrap, and go shopping.
:innocent:

Ozone belcher!
Stay away from my rubber tires and brake hoods!:eek::p

Chombi