Frame bend: hopeless?
 

Wondering if this is hopeless or is it repairable?
https://cimg8.ibsrv.net/gimg/bikefor...02d9b1362.jpeg

Is the down tube bent? It’s hard to tell from the pic. Aluminum bikes are generally not fixable when it’s bent, and
this is kind of a low end aluminum frame so it’s not worth fixing anyways.

Nope. A wrinkle like that is not fixable in any frame material.

Agree, not fixable, metal too thin so would need an expert weld job, gussetting to improve strength all of which would
ruin the temper of the remaining aluminum setting it up for further failure. FWIW had this happen on a 531 steel frame
which was twice welded and eventually failed completely when I was 20 miles out leaving only the top tube holding
the wheels together. Dicey ride home that day.

Aluminum frames are welded together then heat treated with a soak at 800+F° for an hour with slow cool thereafter
to temper the frame.

I suspect a close exam of the top tube near the headtube will show some damage there as well.

It looks like it has taken a pretty hard front end hit. Meaning the frame needs to be stretched back out and either the tube repaired or replaced.

It is doubtful that any frame builder would touch it.

Also carefully inspect the top tube for similar damage.

Other than what likes a nick or scratch on the J, how did that happen without damaging any other area?

That is a very classic front end collision dent. It occurs behind any lugs or internal butting of the tubes (thicker tubing at ends).

In most cases, there will also be damage to the top tube, although in this case it doesn't appear very noticeable.

Some bikes will be rideable with the damage others won't. It can affect both head tube angle and front tire (or fender) clearance.

There is a lot of fear of sudden failure with aluminum and carbon fiber frames.

There is a Park tool (HTS-1) designed to fix this type of damage.

https://www.kurtkaminer.com/parkframestraightener2.jpg

However, it will leave much of the stress in the frame,and I don't think anybody would recommend using it on an aluminum frame. Perhaps straighten the frame, then add gussets as was mentioned above. But, it still would be quite a kluge.

Yes, Hopeless. strip the parts, scrap the frame

How was it welded?

The tubing would have initially been mandrel formed, or hydroformed to shape and thickness, thin in the middle, thick at the ends for welding (thus the bend away from the head tube.

The place that bent was thinner.

The tubes may have been left annealed after forming, or heat treated for strength.

Many of the alloys such as 6061 are weldable, with moderate reduction of strength.

The strength can be regained with heat treatment. I can't say everyone working with aluminum heat treats, but many apparently do.

Someone doing repairs likely could replicate the heat treating cycle, but that would also destroy 100% of the paint, and be an additional, fairly specialized step.

Thanks everyone. I figured it’s a lost cause. I’ve been stripping everything off.

it was actually a front end collision (whoever guessed that was spot on). My son “doing tricks” without a helmet. He ran into a parked trailer with the ramp up. Needless to say there was a hospital visit and 15 stitches to his scalp.

in an instant a $700 bike was reduced to parts. Odd thing was there was no other damage to the bike. Front rim was even fine. I’m still heartbroken about the bike though.

I'd hunt on your local Craigslist for a compatible frame that you could transfer most of your components over to. Not necessarily a Jamis, but something that works for you.

That’s what I’ve been doing. Nothing has come up, or I don’t know what will work.

Not advisable to use that on an aluminum frame. The only real repair option for the OP is replacing the down tube, which, unless the OP can do the work him/herself, is unlikely to be cost effective.

Add a location to your profile.

Is this your bike, or your kid's bike? What are the "specs" you're looking for?

I could probably dig around the bone yard to see if anything pops up. I have a dented aluminum frame that I'll probably never use. :)

It would take a lot of skills and tools to rescue this frame... Here's a safer modification to consider...


https://cimg9.ibsrv.net/gimg/bikefor...0493fd21d.jpeg

But seriously this frame is toast and unsafe even if fixed. Sadly this aluminium may only be worth 0.20 USD a pound stripped of the stem, crank, and bottom bracket...

sorry, I’m just outside of Madison, WI. Updated profile.

I still have to get the bottom bracket off and then will more.

was there a picture in your last post?

A little tongue in cheek, but the frame is real.

About 55cm top tube.
51cm center bottom bracket to top of top tube along seat post
56cm center bottom bracket to mast.

It is currently configured with Ultegra 24mm through BB cranks. I keep the groupset except for bottom bracket, and the seat post if you need it.

https://cimg0.ibsrv.net/gimg/bikefor...60f7f684a2.jpg
https://cimg2.ibsrv.net/gimg/bikefor...553010f9c8.jpg
https://cimg4.ibsrv.net/gimg/bikefor...270f23a1b3.jpg

Between a dime and nickel sized dent in the rear half of the top side of the top tube. The dent is a little sharp near the right edge of the frame.

The frame has been sitting for a while. I'd need to strip and inspect it. But, could make a deal on it.

I see, not a lot of good stuff around Madison.

This'd be fun!!!
https://milwaukee.craigslist.org/bop...298017543.html

There seem to be quite a few good frames in Chicago, for varying prices.

maybe you don’t check your messages on here much, Clifford, but I’m curious what you would want for the frame minus group set.