Seperated Rim Seam?
#26
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And here is what they say about the pin joint
PIN JOINT
Pin joint rim offers more stability. The two channels add more weight and stiffness to the profile. Pin joint rims and Internal safety line work together in one design unit.
Pin joint rim offers more stability. The two channels add more weight and stiffness to the profile. Pin joint rims and Internal safety line work together in one design unit.
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Gold Fever Three days of dirt in Colorado
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100% OK. this was the condition all along, and based on appearances, has been this way for a looooong time. No reason to think anything is going to change now.
Consider, the rim is being held together by the spoke induced compression, and kept from shifting sideways by the internal pin, and the force of the beads pressing on the sides. Where and how can anything move?
FWIW - the problem is that the extrusion was cut square, so there was a bit of a missing pie wedge when it was formed into a circle. This wasn't at all rare BITD, and has never caused issues, except for obsessive, paranoid, super finicky, forum reading cyclists.
Consider, the rim is being held together by the spoke induced compression, and kept from shifting sideways by the internal pin, and the force of the beads pressing on the sides. Where and how can anything move?
FWIW - the problem is that the extrusion was cut square, so there was a bit of a missing pie wedge when it was formed into a circle. This wasn't at all rare BITD, and has never caused issues, except for obsessive, paranoid, super finicky, forum reading cyclists.
I've heard of long-distance touring cyclists who have cut rims in half in order to carry them on long trips...Then they can rebuilt a wheel out in the field. The spokes hold it all together.
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Sailboats have sailed the harshest waters on this planet with masts just sitting either on a pin or in a cup and nothing more than rigging tension holding it in place. And in waters like the Southern Ocean, more than one boat has been rolled over 360 and those mast never fall out. Well they do break occasionally. (Wire rigging has a lot in common with the wire spokes we use to keep the rim where it belongs.)
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Not an obvious marker of a low end rim at all. Even welded rims are pinned. I’ve broken down many rims for scrapping and they all have pins. It’s how the rim is held together so that it can be welded.
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Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
#32
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After the extrusion is formed into a hoop, it moves to the drilling station
It's the operator's job to find the seam and orient it to a reference mark in the fixture. Since it's non-critical it's done to eyeball tolerance, and I expect that a decent worker can easily keep it within few millimeters on either side.
Sometimes they get distracted and miss.
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Here are a few images of such a line on a rim that failed.



Fortunately this was a rear wheel and the tire pressure held it together enough to get home on. When I deflated the tire to check the badly out of true rim the rim tacoed. I was really lucky that it didn't do that on the ride.
Also, to me it looks ike the beginning of a vertical crack between the letters M and I on the tire.
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Your rim is a different story. It was obviously in some sort of incident. I personally wouldn't ride it except maybe around the block.
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BITD, welded rims were the exception rather than the rule. Cheap pinned rims may not line up the ends of the extrusion well, causing a "thunk" when braking, every time the seam passes through the brake blocks. This can be fixed with a file, or, in the case of a front wheel, often just by turning the wheel around in the fork ends so the protruding lip trails the brake blocks rather than leading it.
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Did you say you are going to flip this bike? How much do you think you can get for it?
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.....
The dark line referenced s VERY unlikely to be the beginning of a crack, since it smoothly crosses the joint. It's most likely to be a rubber scuff from the brake shoes, or some tar tracked onto the rim.
The tire concern is likewise overblown, and seems to be no more than the kind of cosmetic scratch tires are prone to.
Of course the OP might give both a closer look, but he needs to insulate himself from overblown issues.
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“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
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#40
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The wheelset and groupset are worth more on a much prettier frame.
Pretty bikes that look newish puts noticable money in my pocket. Vintage crap does not (see a previous reply of mine on this thread.)
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I can't believe the amount of doom and gloom on this thread. Bicycles are not use once and discard items. They last a long time, and obviously will not stay in pristine condition forever
Of course the OP might give both a closer look, but he needs to insulate himself from overblown issues.
Of course the OP might give both a closer look, but he needs to insulate himself from overblown issues.
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About 20 years ago, I had a rear wheel on my recumbent that was making a mysterious thumping noise. Looked closer...

At Rusty Spoke a while ago, a customer brought in a 20-spoke aero road wheel where 5 of the spoke holes (25%) showed visible cracking and deformation. Became a parts donor in a hurry.

At Rusty Spoke a while ago, a customer brought in a 20-spoke aero road wheel where 5 of the spoke holes (25%) showed visible cracking and deformation. Became a parts donor in a hurry.
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If you're curious about my work/local market these are the bikes i'm currently selling:
https://www.trademe.co.nz/a/search?m...isting=6820063
A New Zealand dollar is about 60 US cents.
Last edited by Soody; 12-08-22 at 06:37 PM.
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I know about the rim cracking issue. Tonnes of bikes come in with signs of cracks appearing or that are extremely concave. I agree it's not safe. Usually cut the spokes and take them to the metal recycling place every few months for $2/KG on allum or 20c/KG on steel
These ones are fine though on that front.
These ones are fine though on that front.
#46
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One way to learn better skills is focus on volume. Start working on new finds right away and complete them. Find good sources for parts and supplies, local and mail order. Don't have them turn into "project bikes" that will just stay in pieces forever and depress you.
The more you churn out, the better you get at tackling any repair like any good shop wrench. It's an amazing feeling you get when you've done your first headset overhaul, your first bottom bracket swap, or your first true wheel.
Get your finished bikes out to market fast. They should sell in reasonable time. It's ok to have a few unicorns that can take months to sell, but majority of your flips should sell within weeks if not days. Each one that turns into cash, makes room for the next one.
Flipping bikes is fun and can be profitable if your collection is made up of what sells and what people buy. That's exactly what a used bike shop is about.
There's one flipper in my town and all he does is unicorns and vintage. He has about 150 bikes in his house and sells about half dozen bikes a year. I keep tabs on him so I can remain in constant fear to never turn into that guy.
#47
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Keep it up.
One way to learn better skills is focus on volume. Start working on new finds right away and complete them. Find good sources for parts and supplies, local and mail order. Don't have them turn into "project bikes" that will just stay in pieces forever and depress you.
The more you churn out, the better you get at tackling any repair like any good shop wrench. It's an amazing feeling you get when you've done your first headset overhaul, your first bottom bracket swap, or your first true wheel.
Get your finished bikes out to market fast. They should sell in reasonable time. It's ok to have a few unicorns that can take months to sell, but majority of your flips should sell within weeks if not days. Each one that turns into cash, makes room for the next one.
Flipping bikes is fun and can be profitable if your collection is made up of what sells and what people buy. That's exactly what a used bike shop is about.
There's one flipper in my town and all he does is unicorns and vintage. He has about 150 bikes in his house and sells about half dozen bikes a year. I keep tabs on him so I can remain in constant fear to never turn into that guy.
One way to learn better skills is focus on volume. Start working on new finds right away and complete them. Find good sources for parts and supplies, local and mail order. Don't have them turn into "project bikes" that will just stay in pieces forever and depress you.
The more you churn out, the better you get at tackling any repair like any good shop wrench. It's an amazing feeling you get when you've done your first headset overhaul, your first bottom bracket swap, or your first true wheel.
Get your finished bikes out to market fast. They should sell in reasonable time. It's ok to have a few unicorns that can take months to sell, but majority of your flips should sell within weeks if not days. Each one that turns into cash, makes room for the next one.
Flipping bikes is fun and can be profitable if your collection is made up of what sells and what people buy. That's exactly what a used bike shop is about.
There's one flipper in my town and all he does is unicorns and vintage. He has about 150 bikes in his house and sells about half dozen bikes a year. I keep tabs on him so I can remain in constant fear to never turn into that guy.
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#48
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The thumping, in my experience, is more of a feeling (pulsation) in the brake lever, and is the earliest sign of impending rim separation along the brake track.

This one was thumping pretty good... also a rear wheel.

A more "radial" view.
#49
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I can't believe the amount of doom and gloom on this thread. Bicycles are not use once and discard items. They last a long time, and obviously will not stay in pristine condition forever
.....
The dark line referenced s VERY unlikely to be the beginning of a crack, since it smoothly crosses the joint. It's most likely to be a rubber scuff from the brake shoes, or some tar tracked onto the rim.
The tire concern is likewise overblown, and seems to be no more than the kind of cosmetic scratch tires are prone to.
Of course the OP might give both a closer look, but he needs to insulate himself from overblown issues.
.....
The dark line referenced s VERY unlikely to be the beginning of a crack, since it smoothly crosses the joint. It's most likely to be a rubber scuff from the brake shoes, or some tar tracked onto the rim.
The tire concern is likewise overblown, and seems to be no more than the kind of cosmetic scratch tires are prone to.
Of course the OP might give both a closer look, but he needs to insulate himself from overblown issues.
Can you be certain just from looking at the ops images that the dark line running along the rim near the top is NOT a crack nor the beginning of a crack? Wouldn't the OP be wise to check it to make sure?
Cheers
Cheers
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