Derailleur sludge!

[vavavroom]

So the bike vendor sent replacement bearings. I warned my friend that there was only a slim chance they'd sens the correct bearings. They didn't. The original bearing is 20x42x12. They ordered him five 15x42x13.

When I removed the wheel and the original bearing I realized that one of the two screws that held the collar that's on the axle between the wheel and the axle bearing had broken off. More joy. I guess I'll try to extract and replace that one. Or maybe just leave it as is. This trike is doomed.



Old bearing and new bearing. Not only was the bearing they sent the wrong size but it was missing the dust seal on one side. I told him what bearing to order. The bike will be out of warranty in a couple of months. Not that the warranty has been any good so far!

 

[vavavroom]

I installed the new bearing into the rusty less than the one-year-old wheel. Pearls before swine. At least thing is running again - for now. I saw more sludge on the chain and derailleur.

 

[vavavroom]

Oh snap! My friend sent me a picture of his latest mishap with his Chinese e-trike. The chainstay snapped. It snapped of course while he was riding it. Like the Titanic, his ride was listing heavily and I'm pretty sure the left chainstay side suffered significant stress from being twisted when the right chainstay snapped. This is an aluminum frame. Pretty thin metal. Consider trike and rider top out at nearly 400 lbs (at stillstand and not counting inertial forces).

In my opinion, there's only one way to fix this and it's not worth it because getting this done will cost too much and that trike is going to suffer other structural failures soon anyway. One could replace both chainstays if one had access to a frame builder who's willing.

Other people suggested:

Just arc-weld it. Sure, you go ahead and arc-weld aluminum. I need to see that.

MIG or TIG-weld it. I'm sure you can learn how to MIG and TIG weld in 10 minutes. I need to see that.

Put a steel sleeve over and/or a steel rod inside the chainstay. That will surely work. Can't see new stress fractures happening anytime soon. I gotta see this.

Put a wide band clamp around. I don't see why not. He's going to wear full body armor and a helmet riding this thing until it disintegrates under him, right?

Cooler heads with smarter brains prevailed and, after a 5-minute brainstorming session, convinced him to approach the problem with JB Weld and a wide band clamp. That's surely the best idea yet. Why didn't I think of that?

I wish I was kidding, but that's where we stand. I told him he'll get maimed if he goes through with his plan. He acknowledged my concerns and proceeded to order JB Weld on Amazon.

 

[MRC01]

From what you've described about the rider/owner, he probably feels like he's got nothing to lose. Might as well have fun and live on the edge!

 

[vavavroom]

From what you've described about the rider/owner, he probably feels like he's got nothing to lose. Might as well have fun and live on the edge!

That's what worries me. The chainstay has been epoxied. I'll see if I can get him to send me a picture.

 

[MRC01]

When I was a kid I had a Huffy bike whose frame cracked where the front downtube joined the bottom bracket. My dad epoxied it with something similar to JB Weld, but it was more than 40 years ago so I don't know exactly what product he used. That bike broke in half while I was riding it a few weeks later.

PS: on the other hand, a friend of mine has a steel bike frame whose chainstays cracked similar to the photo you showed. He went to his dad's metal shop and they fabricated a bracing cage and welded it into place.

I wouldn't advise fixing that, but if I had to, I'd jam a steel rod of appropriate diameter through the center of the tubes so it press-fits together with a friction tight fit. Then wrap it with something. Maybe fiberglass cloth saturated with epoxy similar to some boats & airplanes. The epoxy cloth holds it together and the steel rod inside bears the load.

 

[vavavroom]

When I was a kid I had a Huffy bike whose frame cracked where the front downtube joined the bottom bracket. My dad epoxied it with something similar to JB Weld, but it was more than 40 years ago so I don't know exactly what product he used. That bike broke in half while I was riding it a few weeks later.

PS: on the other hand, a friend of mine has a steel bike frame whose chainstays cracked similar to the photo you showed. He went to his dad's metal shop and they fabricated a bracing cage and welded it into place.

I wouldn't advise fixing that, but if I had to, I'd jam a steel rod of appropriate diameter through the center of the tubes so it press-fits together with a friction tight fit. Then wrap it with something. Maybe fiberglass cloth saturated with epoxy similar to some boats & airplanes. The epoxy cloth holds it together and the steel rod inside bears the load.

I'm pretty sure that a steel rod insert (or an outer steel sleeve) will create new stress points and eventually a fracture where the rod/sleeve ends. Also, the other chainstay was twisted longitudinally and is on limited time also. I am convinced the bike was carefully designed to make it just past the 1-year warranty period. I have not yet received a picture of the "repair."

 

[MRC01]

I'm pretty sure that a steel rod insert (or an outer steel sleeve) will create new stress points and eventually a fracture where the rod/sleeve ends. Also, the other chainstay was twisted longitudinally and is on limited time also. I am convinced the bike was carefully designed to make it just past the 1-year warranty period. I have not yet received a picture of the "repair."

You would of course taper the ends of the steel rod insert to reduce the stress at the ends. But yes, of course anything you do is temporary when the original structure is so poorly designed and built. And if the repair is strong enough, you're just getting the frame to the failure of the next weaker item.

 

[vavavroom]

The trike with the broken frame has been junked. My friend bought a Rad Power trike. I put it together for him a few days ago. It's of much better (Made in Taiwan) quality than the previous Chinesium and it comes with a manual with torque specs and local support is available. Single speed with 5 levels of power assist. The hub motor is weaker and the lack of a suspension fork should help with durability. The old trike could go 40mph while new one tops out at 15-20mph. Disc brake in the front, one coaster brake in the rear. If only I can get him to keep the chain clean. I showed him how to apply white Lightning chain lube and gave him a bottle. I hope this trike will last longer than one year.

 

[MRC01]

... The old trike could go 40mph while new one tops out at 15-20mph. ...

Where's the fun in that?

... My friend bought a Rad Power trike. ... If only I can get him to keep the chain clean. I showed him how to apply white Lightning chain lube and gave him a bottle. I hope this trike will last longer than one year.

Seems an ideal application for belt drive.

 

[vavavroom]

Where's the fun in that?

He's older with Parkinson's. His wife wanted him to stick with his electric wheelchair. He wanted an electric bicycle with pedal assist. He needs to exercise or his ability to walk will get worse. I suggested the three-wheeler as a compromise two years ago. He had much fun with the 3Score trike but it wasn't built for a guy his size or for the coastal environment, it did not have a service-friendly design, and there was a lack of support. They repeatedly sent the wrong spare parts. Things kept breaking.

Seems an ideal application for belt drive.

Belt drive doesn't need lube, does it? I wanted him to try White Lightning because it may keep the chain cleaner than the other options since it's supposed to be shedding dirt. More frequent reapplication will be easier for him than cleaning the chain all the time. He can't sit on the ground or kneel and get back up. He'd be flopping around like a fish on land. He rides his trike in a windy marine environment with sand and salty air and belt drive would be best but it's not available on e-trikes. Rad Power just rolled out their e-trike. The wait was one month. Will have to wait and see how it goes and make changes as needed.

I'd like to convert my Motobecane to belt drive, but I have not looked into compatibility with the Nexus-8. This combination would make for years of service-free operation.

 

[MRC01]

... Belt drive doesn't need lube, does it? I wanted him to try White Lightning because it may keep the chain cleaner than the other options since it's supposed to be shedding dirt. ...

Correct, belt drive is dry.
If you're going with wax for lube, the best practice is to remove the chain from the bike and fully degrease it, then soak the clean dry chain in melted wax overnight. After that, you can periodically reapply wax based lube without removing the chain from the bike.

 

[vavavroom]

Correct, belt drive is dry.
If you're going with wax for lube, the best practice is to remove the chain from the bike and fully degrease it, then soak the clean dry chain in melted wax overnight. After that, you can periodically reapply wax based lube without removing the chain from the bike.

I can't see him taking the chain off, cleaning it, soaking it in wax, and reinstalling it. He's got the shakes badly even on a good day. I can't be his bike mechanic on call. I live 50 miles from him and I go check on him in person maybe once a month. My concern with White Lightning is the potential for waxy buildup over time. However, I'm sure it will perform better than sticky lube that will be loaded with sand and dog fur. I think I posted a picture of the old trike's furry derailleur in this thread some time ago.

 

[vavavroom]

The new trike is not a 26" fat tire trike like the old one was. The old trike had an underdesigned aluminum frame, this one is steel and seems much more solidly built. The skimpy seat post strut has me a little worried. My friend is a heavyweight. This trike has the capacity to carry 350 lbs. The rear basket hasn't come in yet. Sand and more sand. Sand with dog turds and fur. It's unavoidable.

 

[853okg]

Boeshield is immeasurably better than White Lightning. I absolutely would not repair that trike, and my motto is safety third. But that’s a lost cause.

 

[vavavroom]

Boeshield is immeasurably better than White Lightning. I absolutely would not repair that trike, and my motto is safety third. But that’s a lost cause.

As I already mentioned the old trike has been junked. It took a lot of work to convince him to part with it.

 

[sk_pete]

LoL 3wd