Can a cracked frame be repaired?

[oldbeagle]

Got a lot of questions of late... Warmer weather coming soon...

My Superdart kart has a crack in the frame. I don't think it is bent, but just a partial cracking of the frame tubes on the bottom of frame. It's at the joint where the steering wheel hoop connects to the right side main frame rail and then an upper frame rail attaches at the top of the same joint.
Would a competent welder be able do a permanent fix on it? I will not restore or ride until until I get it repaired somehow. I have no idea how it can be fixed otherwise.

I did have an old 2seater kart once that had a hot 5hp engine on it and it cracked the motor mounts all the time until some angle iron was welded over the frame pipe where it cracked. I don't want that kind of crude repair on my superdart!

 

[colestreasures]

Either replace with chrome moly tubing the same size, or repair it and possibly support it . Where you say its cracked and probably should be supported IMHO, Either way your going to be doing some welding on it. JMO some pics would be nice also.
Cole

 

[jandj]

There aren't that many Superdarts left so my advice would be don't cut anything you don't have too.
A good welder can do the job just fine, maybe find out who the local stock car guys use.
They'll be able to repair it and you can grind it smooth so nobody will know it's been done.

 

[colestreasures]

I agree I wouldn't cut it up no no , but I also wouldn't let just anyone weld on it either, it would all depend on just how much ride time your going to be doing on it, it can be welded and be solid, but usually I said usually if it is rode alot and pretty hard st times it will eventually Crack again but not the same place, more then likely it will be beside the new weld, as time goes by that is, just saying whatever you do do it so that you don't take away from the value of the kart, like stated not that many of them left. Goodluck with whatever you end up doing. And I would really like to see the kart your working on.
Cole

 

[jandj]

http://www.diygokarts.com/vb/attachment.php?attachmentid=49692&d=1404691360
Here's his Superdart.
It's basically a Rupp A Bone with an extended porch and a few other tweaks.
It was built for dirt ovals which is why so many have had nerf bars and bumpers added.
Those wide wheels aren't stock either, it would have had Rupp Turbines or Van K wheels.
Being a dirt oval kart is also why so many have the stress cracks like his does.
Once it's repaired it should hold.
I doubt it will ever again be used as hard as it was during it's racing life.

 

[colestreasures]

http://www.diygokarts.com/vb/attachment.php?attachmentid=49692&d=1404691360
Here's his Superdart.
It's basically a Rupp A Bone with an extended porch and a few other tweaks.
It was built for dirt ovals which is why so many have had nerf bars and bumpers added.
Those wide wheels aren't stock either, it would have had Rupp Turbines or Van K wheels.
Being a dirt oval kart is also why so many have the stress cracks like his does.
Once it's repaired it should hold.
I doubt it will ever again be used as hard as it was during it's racing life.

Ok now that I have seen his kart , i was wondering how much it was like the A-bone, and i do agree where it's cracked a good welder should be able to fix that no problem, I was just a little concerned about how it would be rode never know. Just concerned over all that's it.
Cole

 

[jandj]

Understood!

 

[oldbeagle]

ok, with all this talk, I'm gonna get the superdart out of the shed and set it up and take lots of pics of it for you guys. It has margay 62 series wheels which I like although they use tubes. Did have it running shortly about 20 years ago. Currently sits stripped of paint and with light coat of primer.

 

[DeathMachine]

If you want to have a worry free repair, slug the frame. Chopper builder do this when they stretch or hard tail a frame.

All it is is a short length of steel round stock that is slipped into the frame. Select a size that is a snug fit, may have to turn it down or grind to fit. Cut it a few inches long. Cut the frame at the crack so you can insert the slug, drill a hole near, but not past, where each end of the slug will end up.

Insert the slug, weld it in where the hole was drilled, then slide the frame over the slug and weld the other end. Weld the joint, and grind and finish the joint smooth. It will be stronger than the original tube.