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Re: Help - I'm really overthinking wheel choice [Ryanppax] [ In reply to ]
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Ryanppax wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
Why didn't they wipe the dirt off of it?


My exact thought also. Why take the time to post an expensive disc wheel that is dirty.

Also, why I suggested not buying from someone who doesn't have 100% rating was for his situation, which is buying a big ticket item from an unknown source. Plus, if he gets it and it doesn't work for him, he's out of luck...and money.

I err on the side of caution when looking at reviews and pics of things, as well as percent rating. Under 98, an automatic no go for me.



How would you lose your money when buying from an eBay seller and the product is broken or doesn't work?


Not willing to find that out. There's typically a reason the ratings are the way they are...I do research their rating before buying or deciding not to buy. But, in the end, it my money and my call.



Have you ever read eBay's Money Back Guarantee?


Welcome to the Fuck around and find out portion of the story.

Both wheels were from the same seller.
Rear wheel showed a little warping in the rim bead..didn't seem too bad. Upon further inspection on another part of a wheel it is cracked. So we will see how good that money back guarantee is.
Front wheel looked fine but after finding a problem with the rear i gave it another look. Put it on the bike and it's very out of true.. Is this a show stopper or fixable.
Pics and vid attached.

https://photos.app.goo.gl/fX2Fczbhc9LFb7QT6


Edit: refund in the works with seller



The eBay Money Back Guarantee is as solid as it gets. If you file a SNAD complaint, you will get a 100% refund and the seller gets to pay for return shipping.

I purchased four sets of glassware (coupes, nick and nora, martini glasses) from a seller in Italy in December. All of them were chipped or broken in transit. I filed a SNAD complaint with eBay for each purchase and received all of my money back.

I have done this at least twenty times in the past ten years.
Last edited by: jimatbeyond: Jan 22, 24 23:14
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Re: Help - I'm really overthinking wheel choice [Mudge] [ In reply to ]
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Mudge wrote:
mathematics wrote:
DrAlexHarrison wrote:
What convinced you that 28mm was faster than 23 or 25mm when considering aero & rr? (and weight, but let's not get crazy down in the weeds just yet).

I'm curious because I was still of the mind that 25-27mm measured width might be faster than 28-30mm widths, in most cases. (Due to aero)

I might be behind the times.


This doesn't always hold true because there's a hundred different tyresand wheels, but generally having a tire that is narrower (when inflated, actual width) than the rim will be more aero than the other way around. To my understanding this is mainly due to the trailing edge, and how horribly inefficient a round body is at the back of the airflow.

You could run a 21-23mm on a 25mm rim, but the rolling resistance in most cases would outweigh the aero benefits. On a 27mm rim you could run a 25mm tyre and get lower rr for marginally worse aero. In all likelihood 21mm rims are faster at higher speeds and 27mm rims are faster at lower speeds, but again, very dependent on rim shape and tire selection.

I realize this isn't helpful at all.


It's not a given that a wider tire is faster when you make appropriate adjustments for pressures. There a number of useful charts in this test report, but so you don't have to do the mental gymnastics, there's a chart that already shows what happens when you make said appropriate adjustments to pressure as the tires get wider. Spoiler: the 23mm is fastest.

https://www.bicyclerollingresistance.com/...prix-5000-comparison

In these charts the minimum RR is the 32mm with 7.8w where the 23 was the slowest at 8.5w. They do a test with a 15% tire drop, but as they even state, that's not a great test as 15% of a 32mm is more than 15% of 23mm. One of the reasons for running wider tires is to reduce this drop and theoretically reduce rolling resistance. Right below that is a test with a 4mm drop that shows a straight line among tires. This is a better test, but keep in mind that a 4mm drop with static weight says nothing about the tire's ability to absorb road imperfections larger (or smaller) than the diamond plate roller. Stands to reason the 23 would be fastest on a wooden track at high psi and the 32 would be fastest on gravel at low psi, but we intuitively knew that already.

Finally, and most importantly, all of these tests were done on a 700x17mm rim. That setup is going to heavily favor a narrower tire with the hysteresis losses on the ballooned out wide tire being comparatively greater than if they were on a wider rim. The cross sectional degrees that the tire encompasses are greater for a wider tire or narrower rim.
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Re: Help - I'm really overthinking wheel choice [Rocky M] [ In reply to ]
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When a company is having a problem getting their stickers to stick on a wheel. Not sure I’m going to have a lot of trust going down the hill at 40 miles an hour in that wheel

A few hundred bucks saved isn’t worth my life
Last edited by: MrTri123: Jan 23, 24 6:29
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Re: Help - I'm really overthinking wheel choice [mathematics] [ In reply to ]
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mathematics wrote:
Mudge wrote:
mathematics wrote:
DrAlexHarrison wrote:
What convinced you that 28mm was faster than 23 or 25mm when considering aero & rr? (and weight, but let's not get crazy down in the weeds just yet).

I'm curious because I was still of the mind that 25-27mm measured width might be faster than 28-30mm widths, in most cases. (Due to aero)

I might be behind the times.


This doesn't always hold true because there's a hundred different tyresand wheels, but generally having a tire that is narrower (when inflated, actual width) than the rim will be more aero than the other way around. To my understanding this is mainly due to the trailing edge, and how horribly inefficient a round body is at the back of the airflow.

You could run a 21-23mm on a 25mm rim, but the rolling resistance in most cases would outweigh the aero benefits. On a 27mm rim you could run a 25mm tyre and get lower rr for marginally worse aero. In all likelihood 21mm rims are faster at higher speeds and 27mm rims are faster at lower speeds, but again, very dependent on rim shape and tire selection.

I realize this isn't helpful at all.


It's not a given that a wider tire is faster when you make appropriate adjustments for pressures. There a number of useful charts in this test report, but so you don't have to do the mental gymnastics, there's a chart that already shows what happens when you make said appropriate adjustments to pressure as the tires get wider. Spoiler: the 23mm is fastest.

https://www.bicyclerollingresistance.com/...prix-5000-comparison


In these charts the minimum RR is the 32mm with 7.8w where the 23 was the slowest at 8.5w. They do a test with a 15% tire drop, but as they even state, that's not a great test as 15% of a 32mm is more than 15% of 23mm. One of the reasons for running wider tires is to reduce this drop and theoretically reduce rolling resistance. Right below that is a test with a 4mm drop that shows a straight line among tires. This is a better test, but keep in mind that a 4mm drop with static weight says nothing about the tire's ability to absorb road imperfections larger (or smaller) than the diamond plate roller. Stands to reason the 23 would be fastest on a wooden track at high psi and the 32 would be fastest on gravel at low psi, but we intuitively knew that already.

Finally, and most importantly, all of these tests were done on a 700x17mm rim. That setup is going to heavily favor a narrower tire with the hysteresis losses on the ballooned out wide tire being comparatively greater than if they were on a wider rim. The cross sectional degrees that the tire encompasses are greater for a wider tire or narrower rim.


The 7.8w minimum RR figure for the 32mm wide tire came at a pressure that no one would/could ever ride IRL, so that figure is meaningless. IOW, an untenable course of action is not a course of action. You can and should disregard that figure. Whether you want to use the simplistic 15% drop, or extrapolate the resistance by taking reasonable real life pressures from the earlier charts in the report, what you'll find is that for all intents and purposes, there's nothing in it. For a given tire model, when adjusting the pressures relative to the width, the rolling resistance differences are minimal. With that in mind, the question then becomes one of which tire/rim combo is aero optimized.

Given that a 28mm nominal width tire will balloon out to 30-32mm or more on a wider internal width rim, to get the magical 1.05 ratio, the outer width of the rim has to be pretty substantial. It's almost a given that such a rim won't work in a rim-brake bike. Seems to me that for most rims, even on disc brake set ups, the optimal nominal tire width would be a 25, as it will balloon out to 27-28mm or so when inflated. You'll get reasonable comfort/traction benefits, essentially identical rolling resistance, and far better aero drag figures than you would with an even wider tire.

Before anyone pipes in with "but the pros are going to 32s", keep in mind that they're only doing that for road racing, not time trials. The considerations change when drafting is introduced and pure aero optimization isn't so important.
Last edited by: Mudge: Jan 23, 24 8:33
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Re: Help - I'm really overthinking wheel choice [MrTri123] [ In reply to ]
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MrTri123 wrote:
When a company is having a problem getting their stickers to stick on a wheel. Not sure I’m going to have a lot of trust going down the hill at 40 miles an hour in that wheel

A few hundred bucks saved isn’t worth my life
Given your paucity of information it does not mean the wheel is the problem. It could entirely be the sticker manufacturer's glue. Cee Gees had batches of bad glue on their arm rests--does that mean you wouldn't use them ever because of it? I would hardly judge a brand off an issue with stickers. The reviews of LB were very good actually, even used by mountain bikers for AT riding. People probably shouldn't use Zipp wheels then either--because of the past hub & QR recalls/issues they had (and all the weight is on those two components of a bike)...
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Re: Help - I'm really overthinking wheel choice [Mudge] [ In reply to ]
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Mudge wrote:
mathematics wrote:
Mudge wrote:
mathematics wrote:
DrAlexHarrison wrote:
What convinced you that 28mm was faster than 23 or 25mm when considering aero & rr? (and weight, but let's not get crazy down in the weeds just yet).

I'm curious because I was still of the mind that 25-27mm measured width might be faster than 28-30mm widths, in most cases. (Due to aero)

I might be behind the times.


This doesn't always hold true because there's a hundred different tyresand wheels, but generally having a tire that is narrower (when inflated, actual width) than the rim will be more aero than the other way around. To my understanding this is mainly due to the trailing edge, and how horribly inefficient a round body is at the back of the airflow.

You could run a 21-23mm on a 25mm rim, but the rolling resistance in most cases would outweigh the aero benefits. On a 27mm rim you could run a 25mm tyre and get lower rr for marginally worse aero. In all likelihood 21mm rims are faster at higher speeds and 27mm rims are faster at lower speeds, but again, very dependent on rim shape and tire selection.

I realize this isn't helpful at all.


It's not a given that a wider tire is faster when you make appropriate adjustments for pressures. There a number of useful charts in this test report, but so you don't have to do the mental gymnastics, there's a chart that already shows what happens when you make said appropriate adjustments to pressure as the tires get wider. Spoiler: the 23mm is fastest.

https://www.bicyclerollingresistance.com/...prix-5000-comparison


In these charts the minimum RR is the 32mm with 7.8w where the 23 was the slowest at 8.5w. They do a test with a 15% tire drop, but as they even state, that's not a great test as 15% of a 32mm is more than 15% of 23mm. One of the reasons for running wider tires is to reduce this drop and theoretically reduce rolling resistance. Right below that is a test with a 4mm drop that shows a straight line among tires. This is a better test, but keep in mind that a 4mm drop with static weight says nothing about the tire's ability to absorb road imperfections larger (or smaller) than the diamond plate roller. Stands to reason the 23 would be fastest on a wooden track at high psi and the 32 would be fastest on gravel at low psi, but we intuitively knew that already.

Finally, and most importantly, all of these tests were done on a 700x17mm rim. That setup is going to heavily favor a narrower tire with the hysteresis losses on the ballooned out wide tire being comparatively greater than if they were on a wider rim. The cross sectional degrees that the tire encompasses are greater for a wider tire or narrower rim.


The 7.8w minimum RR figure for the 32mm wide tire came at a pressure that no one would/could ever ride IRL, so that figure is meaningless. IOW, an untenable course of action is not a course of action. You can and should disregard that figure. Whether you want to use the simplistic 15% drop, or extrapolate the resistance by taking reasonable real life pressures from the earlier charts in the report, what you'll find is that for all intents and purposes, there's nothing in it. For a given tire model, when adjusting the pressures relative to the width, the rolling resistance differences are minimal. With that in mind, the question then becomes one of which tire/rim combo is aero optimized.

Given that a 28mm nominal width tire will balloon out to 30-32mm or more on a wider internal width rim, to get the magical 1.05 ratio, the outer width of the rim has to be pretty substantial. It's almost a given that such a rim won't work in a rim-brake bike. Seems to me that for most rims, even on disc brake set ups, the optimal nominal tire width would be a 25, as it will balloon out to 27-28mm or so when inflated. You'll get reasonable comfort/traction benefits, essentially identical rolling resistance, and far better aero drag figures than you would with an even wider tire.

Before anyone pipes in with "but the pros are going to 32s", keep in mind that they're only doing that for road racing, not time trials. The considerations change when drafting is introduced and pure aero optimization isn't so important.

Yes, if we don't count the data showing the wider tires being faster then the skinnier tires are faster.

But to the original point, it's likely that the entire system efficiency would be better with a wider aero rim than with a skinny aero rim (disc brakes, as stipulated by OP) no matter the tire choice. Unless it's something ridiculous like a 19mm tire on a 30mm rim. Running a skinny tire on a wide rim may not be super comfortable but is still likely to have better aerodynamics than a wider tire on the same rim. It all comes down to the speed dependent relationship, RR is king at low speed, aero is king at high speed. At the 25ish mph most people tend to race at it's a bit of a toss up for which is more important. That makes sense, if there was a clear way to optimize with wider/narrower tires brands and racers would have shifted towards that.
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Re: Help - I'm really overthinking wheel choice [Ryanppax] [ In reply to ]
Quote | Reply
Ryanppax wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
Why didn't they wipe the dirt off of it?


My exact thought also. Why take the time to post an expensive disc wheel that is dirty.

Also, why I suggested not buying from someone who doesn't have 100% rating was for his situation, which is buying a big ticket item from an unknown source. Plus, if he gets it and it doesn't work for him, he's out of luck...and money.

I err on the side of caution when looking at reviews and pics of things, as well as percent rating. Under 98, an automatic no go for me.



How would you lose your money when buying from an eBay seller and the product is broken or doesn't work?


Not willing to find that out. There's typically a reason the ratings are the way they are...I do research their rating before buying or deciding not to buy. But, in the end, it my money and my call.



Have you ever read eBay's Money Back Guarantee?


Welcome to the Fuck around and find out portion of the story.

Both wheels were from the same seller.
Rear wheel showed a little warping in the rim bead..didn't seem too bad. Upon further inspection on another part of a wheel it is cracked. So we will see how good that money back guarantee is.
Front wheel looked fine but after finding a problem with the rear i gave it another look. Put it on the bike and it's very out of true.. Is this a show stopper or fixable.
Pics and vid attached.

https://photos.app.goo.gl/fX2Fczbhc9LFb7QT6


Edit: refund in the works with seller

That sucks. Sorry to hear about it. I always take a video while I open my big ticket items to document the issues-if any. Over the top, I'm sure, but just want anything and everything documented if needed.
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Re: Help - I'm really overthinking wheel choice [littlefoot] [ In reply to ]
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Seller claiming "ohh it must have been damaged in shipping I sent it in good condition, I had it insured.[circled a little dent in the pic of the box I sent him]..send it back and I'll do a claim"

sounds like hes just pulling shipping insurance scam. whatevs at least I get my money back. IDK how much they'll cost but my team's lbs owner offered to sell his 30mm wide CL50s for "cheap" still waiting for price and pics before I make the hour drive. If the deal is good enough I think I'll grab them. 1st choice is the CLX64 I see on the pros closet now for 700, but if the cl50 is cheap enough I may just do that and get a new disc.

IG - @ryanppax
http://www.geluminati.com
Use code ST5 for $5 off your order
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Re: Help - I'm really overthinking wheel choice [mathematics] [ In reply to ]
Quote | Reply
mathematics wrote:
Mudge wrote:
mathematics wrote:
Mudge wrote:
mathematics wrote:
DrAlexHarrison wrote:
What convinced you that 28mm was faster than 23 or 25mm when considering aero & rr? (and weight, but let's not get crazy down in the weeds just yet).

I'm curious because I was still of the mind that 25-27mm measured width might be faster than 28-30mm widths, in most cases. (Due to aero)

I might be behind the times.


This doesn't always hold true because there's a hundred different tyresand wheels, but generally having a tire that is narrower (when inflated, actual width) than the rim will be more aero than the other way around. To my understanding this is mainly due to the trailing edge, and how horribly inefficient a round body is at the back of the airflow.

You could run a 21-23mm on a 25mm rim, but the rolling resistance in most cases would outweigh the aero benefits. On a 27mm rim you could run a 25mm tyre and get lower rr for marginally worse aero. In all likelihood 21mm rims are faster at higher speeds and 27mm rims are faster at lower speeds, but again, very dependent on rim shape and tire selection.

I realize this isn't helpful at all.


It's not a given that a wider tire is faster when you make appropriate adjustments for pressures. There a number of useful charts in this test report, but so you don't have to do the mental gymnastics, there's a chart that already shows what happens when you make said appropriate adjustments to pressure as the tires get wider. Spoiler: the 23mm is fastest.

https://www.bicyclerollingresistance.com/...prix-5000-comparison


In these charts the minimum RR is the 32mm with 7.8w where the 23 was the slowest at 8.5w. They do a test with a 15% tire drop, but as they even state, that's not a great test as 15% of a 32mm is more than 15% of 23mm. One of the reasons for running wider tires is to reduce this drop and theoretically reduce rolling resistance. Right below that is a test with a 4mm drop that shows a straight line among tires. This is a better test, but keep in mind that a 4mm drop with static weight says nothing about the tire's ability to absorb road imperfections larger (or smaller) than the diamond plate roller. Stands to reason the 23 would be fastest on a wooden track at high psi and the 32 would be fastest on gravel at low psi, but we intuitively knew that already.

Finally, and most importantly, all of these tests were done on a 700x17mm rim. That setup is going to heavily favor a narrower tire with the hysteresis losses on the ballooned out wide tire being comparatively greater than if they were on a wider rim. The cross sectional degrees that the tire encompasses are greater for a wider tire or narrower rim.


The 7.8w minimum RR figure for the 32mm wide tire came at a pressure that no one would/could ever ride IRL, so that figure is meaningless. IOW, an untenable course of action is not a course of action. You can and should disregard that figure. Whether you want to use the simplistic 15% drop, or extrapolate the resistance by taking reasonable real life pressures from the earlier charts in the report, what you'll find is that for all intents and purposes, there's nothing in it. For a given tire model, when adjusting the pressures relative to the width, the rolling resistance differences are minimal. With that in mind, the question then becomes one of which tire/rim combo is aero optimized.

Given that a 28mm nominal width tire will balloon out to 30-32mm or more on a wider internal width rim, to get the magical 1.05 ratio, the outer width of the rim has to be pretty substantial. It's almost a given that such a rim won't work in a rim-brake bike. Seems to me that for most rims, even on disc brake set ups, the optimal nominal tire width would be a 25, as it will balloon out to 27-28mm or so when inflated. You'll get reasonable comfort/traction benefits, essentially identical rolling resistance, and far better aero drag figures than you would with an even wider tire.

Before anyone pipes in with "but the pros are going to 32s", keep in mind that they're only doing that for road racing, not time trials. The considerations change when drafting is introduced and pure aero optimization isn't so important.


Yes, if we don't count the data showing the wider tires being faster then the skinnier tires are faster.

But to the original point, it's likely that the entire system efficiency would be better with a wider aero rim than with a skinny aero rim (disc brakes, as stipulated by OP) no matter the tire choice. Unless it's something ridiculous like a 19mm tire on a 30mm rim. Running a skinny tire on a wide rim may not be super comfortable but is still likely to have better aerodynamics than a wider tire on the same rim. It all comes down to the speed dependent relationship, RR is king at low speed, aero is king at high speed. At the 25ish mph most people tend to race at it's a bit of a toss up for which is more important. That makes sense, if there was a clear way to optimize with wider/narrower tires brands and racers would have shifted towards that.


I'm not discounting the data showing wider tires being faster, I'm factoring in the fact that the only way to get them to be faster is to inflate them to a pressure that is unrideable in the real world. IOW, an untenable course of action is not a course of action. In decision making terms, you stop even considering an untenable course of action.

The conclusion of the test report spells it out:

"A bigger road bike tire (at least the Continental GP 4000 and GP 5000) provides a lower rolling resistance at the same air pressure. You do have to realize that at the same air pressure, a bigger tire will provide a less comfortable ride.
At the 15% tire drop air pressures, which are very close to the recommended air pressures for a given size, the tables are turned and a bigger road bike tire will have a higher rolling resistance."


And of course, there's this:
Rolling Resistance at the Same Comfort Level (4.5 mm tire drop)

Rolling Resistance at the Same Comfort Level (4.5 mm tire drop)TireGP 5000GP 5000GP 5000GP 5000Tire size23-62225-62228-62232-622Inner tubeButyl 100 grButyl 100 grButyl 130 grButyl 130 grTire drop4.5 mm4.5 mm4.5 mm4.5 mmAir pressure92 psi
6.3 bar87 psi
6.0 bar81 psi
5.6 bar75 psi
5.2 barRolling resistance11.3 Watts11.5 Watts11.4 Watts11.4 Watts
Tell me again who's ignoring data?

When normalized for reasonable real world pressures, the RR differences are quite minimal (well within the margin of error of the test). Worrying about the 0.1 W difference between tires when inflated to optimum pressure is akin to picking the fly shit out of the pepper. It certainly seems reasonable that once you've selected the right tire model, you select the size that optimizes drag reduction on your race wheels while inflated to the optimum pressure.
Last edited by: Mudge: Jan 23, 24 14:34
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Re: Help - I'm really overthinking wheel choice [mathematics] [ In reply to ]
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Not so sure it's true that the narrowest tire you can run on any given wheel is the fastest. There were some posts from Jim at ERO talking about enve wheels, saying they were slow with 23mm tires but got a lot faster with 25mm tires. Similarly, I suspect something like the new rapide wheels are faster with a 26-28mm tire than something narrower.
Quote Reply
Re: Help - I'm really overthinking wheel choice [littlefoot] [ In reply to ]
Quote | Reply
littlefoot wrote:
Ryanppax wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
littlefoot wrote:
jimatbeyond wrote:
Why didn't they wipe the dirt off of it?


My exact thought also. Why take the time to post an expensive disc wheel that is dirty.

Also, why I suggested not buying from someone who doesn't have 100% rating was for his situation, which is buying a big ticket item from an unknown source. Plus, if he gets it and it doesn't work for him, he's out of luck...and money.

I err on the side of caution when looking at reviews and pics of things, as well as percent rating. Under 98, an automatic no go for me.



How would you lose your money when buying from an eBay seller and the product is broken or doesn't work?


Not willing to find that out. There's typically a reason the ratings are the way they are...I do research their rating before buying or deciding not to buy. But, in the end, it my money and my call.



Have you ever read eBay's Money Back Guarantee?


Welcome to the Fuck around and find out portion of the story.

Both wheels were from the same seller.
Rear wheel showed a little warping in the rim bead..didn't seem too bad. Upon further inspection on another part of a wheel it is cracked. So we will see how good that money back guarantee is.
Front wheel looked fine but after finding a problem with the rear i gave it another look. Put it on the bike and it's very out of true.. Is this a show stopper or fixable.
Pics and vid attached.

https://photos.app.goo.gl/fX2Fczbhc9LFb7QT6


Edit: refund in the works with seller

That sucks. Sorry to hear about it. I always take a video while I open my big ticket items to document the issues-if any. Over the top, I'm sure, but just want anything and everything documented if needed.


eBay doesn't look at video. You only have to submit one picture of a damaged item.
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Re: Help - I'm really overthinking wheel choice [Ryanppax] [ In reply to ]
Quote | Reply
Ryanppax wrote:
Seller claiming "ohh it must have been damaged in shipping I sent it in good condition, I had it insured.[circled a little dent in the pic of the box I sent him]..send it back and I'll do a claim"

sounds like hes just pulling shipping insurance scam.


As soon as you ship it back to the seller, the seller's original insurance is void because the damage could have occurred during the return shipping. If the seller files an insurance claim, it will be denied.
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