Michelin Pilot Street 2 on the Lynx, is it safe?

[Jayzao]

Let's talk about the Michelin Pilot Street 2 on the Lynx.

Whereas I don't specifically have issues with the stock street tire that was shipped from eWheels on my new Lynx, I had previously installed the Michelin Pilot Street 2 tire on my Begode Master and found it to be sticky, well-rounded and balanced appropriately for that EUC. However, recently, I asked for guidance on appropriate tires, suggesting that tire for the Lynx, and was surprised to find out there may be problems with that specific tire and the Lynx. 

What I learned is that there have been some concerns raised within the EUC community regarding the Michelin Pilot Street tire, specifically the 80/90-17 model, when used on the Leaperkim Lynx. While there aren't many documented cases (that I could find), experienced, skilled riders are discussing the potential for high-speed wobbles or instability, particularly at higher speeds or under specific conditions like downhill riding. These wobbles can be especially dangerous, leading to crashes in severe cases and contributing to serious injuries in one case.

The root cause of these issues is a combination of factors related to the tire design and how it interacts with the Lynx's geometry and weight distribution. Some users have reported that the narrow and high position of the battery packs, combined with the tire's characteristics, might contribute to this instability. Adjusting tire pressure, using aftermarket pedal hangers to lower the center of gravity, and selecting tires with different tread patterns can mitigate these issues, but not entirely.

Folks on this forum understand that tire choice can significantly impact an EUC's handling characteristics. I have learned quite a bit here. What works well for one rider might not work for another. Riders have different preferences for stability, traction, and responsiveness, so it's crucial to consider these factors when choosing a tire.
I may not be a physicist, although I understand and can discuss the concepts well enough to examine the potential root cause(s) with the help of my deep experience here in the community. High-speed instability in Electric Unicycles (EUCs), particularly in the form of wobbles, is influenced by several physics principles. These include gyroscopic precession, resonance, aerodynamic forces, and mass distribution.
I certainly understand that our chosen sport can be subject to unjust scrutiny depending on where we ride and what local regulatory mechanisms are in place. This scrutiny is usually rooted in fear, uncertainty, and doubt. (FUD)

I would like feedback from the community on this issue, as personal injury (safety) is a high priority for every EUC rider—or it becomes a high priority when the universe makes it a priority. 

Does anyone know firsthand of a case where an event like this has occurred? 
Are there potential defects or flaws in manufacturing this particular tire?
Are there known cases where these events have occurred on EUCs aside from the Lynx, with the exact tire or other sizes of this tire in this line?


We have a thread that hints at this topic; however, no clear root cause seems to have been established. 

Happy Friday!
 

 

[RagingGrandpa]

"Unsafe" would mean a tire that doesn't stay seated on the rim during riding, due to mismatch with rim geometry. 
But I don't think any tires have been reported as coming unseated with Lynx.

Or, problems with durability: chunking, delamination, or other failure of the tire material.
Again, none reported.

Stability is a topic of personal preference. It's affected by rim shape, EUC shape, EUC weight, tire shape, tire pressure, firmware, and the rider. We'll all need to find an acceptable blend of these parameters... one person's answer isn't necessarily right for others.

[Clem604]

The Lynx would need a 80/90-14 tire. I can't speak for the Lynx but the Michelin PS2 has been great on my Sherman S.

Edited August 12 by Clem604

[Jayzao]

11 minutes ago, Clem604 said:

The Lynx would need a 80/90-14 tire. I can't speak for the Lynx but the Michelin PS2 has been great on my Sherman S.

I had great luck with the Michelin on my Begode Master v4.
I was interested in buying the same for the Lynx and heard that some folks had issues with the tire on the Lynx specifically. 

[Jayzao]

1 hour ago, RagingGrandpa said:

"Unsafe" would mean a tire that doesn't stay seated on the rim during riding, due to mismatch with rim geometry. 
But I don't think any tires have been reported as coming unseated with Lynx.

Or, problems with durability: chunking, delamination, or other failure of the tire material.
Again, none reported.

Stability is a topic of personal preference. It's affected by rim shape, EUC shape, EUC weight, tire shape, tire pressure, firmware, and the rider. We'll all need to find an acceptable blend of these parameters... one person's answer isn't necessarily right for others.

Perhaps 'unsafe' is not the best word choice. Thanks for the correction. 
I am asking to attempt to validate if, in fact, there is some underlying issue or if this was just a matter of preference. 
I assume it cannot be speed-related, so maybe rim geometry is the root cause. 
 

[techyiam]

In the tire comparo video below, three tires were tested on a Lynx, of which the Pliot Street 2 was one of the tires tested.

I found this video very informative. 

 

Edited August 13 by techyiam