seedubb
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- Location
- Florida, US
Hey all. Long post incoming but I think it's worth the read — especially if you're an EX owner, considering buying one, or have dealt with Stark support on a drivetrain issue.
I love this bike. That's important context for everything that follows. The Varg EX is genuinely one of the most exciting things I've ridden and I want Stark to succeed. This post comes from that place, not from someone who wants to torch the brand.
The short version of my ownership history:
Four months in, seven support tickets. Check engine light on delivery from nearly no coolant. Arkenstone connectivity failure over Christmas that contributed to a small accident — I submitted 7 documented troubleshooting videos, YouTube analytics confirm 6 were never watched. Missing homologation kit hardware. Faulty chain adjuster. Screen protector shipped folded in half. Seat deformed under a cover at 70°F — warranty denied. And now an active, unresolved drivetrain issue that is the reason for this post.
Of those seven issues, Stark resolved two by shipping inexpensive replacement parts. Everything else was denied, unresolved, or fixed through my own research and effort.
The drivetrain issue — here's where I need your help:
I'm experiencing a rhythmic, periodic vibration with a fixed cycle of approximately 3 seconds at all speeds above 45 mph. Severity: just short of teeth-rattling on smooth tarmac. I also notice inconsistent power delivery at steady throttle — the bike perceptibly accelerates and decelerates with the throttle held constant. A second rider has independently confirmed both symptoms.
On performing a gear oil change I found:
I have a background in engineering and computer science. I wrote a Python optical flow analysis script and applied it to ride footage from a body-worn Insta360 GO 3S capturing movement of a bike-mounted Insta360 X5. The script measures frame-to-frame camera displacement as a proxy for chassis vibration.
Results across two clips:
Video:
Stark's response:
Initial guidance was to bring the bike to a dealer — 155 miles away in Tallahassee. When I asked if Stark could pre-coordinate with the dealer before I committed to a 310-mile round trip, the recommendation reversed to "probably fine, just ride normally."
Most recently, after I shared the optical flow analysis, Stark attributed the vibration to knobby tyres on tarmac and stated the service would not be covered under warranty. This contradicts a previous written statement from Stark in a ticket that bearing damage found despite proper maintenance would be covered in full.
Tyres do not put metal in gear oil. A 3-second periodic vibration that doesn't change with speed is not a tyre characteristic. I've disputed this formally and requested a video call with their engineering team.
What I'm looking for:
Happy to share the Python script and analysis methodology with anyone who wants it.
— C.W.
I love this bike. That's important context for everything that follows. The Varg EX is genuinely one of the most exciting things I've ridden and I want Stark to succeed. This post comes from that place, not from someone who wants to torch the brand.
The short version of my ownership history:
Four months in, seven support tickets. Check engine light on delivery from nearly no coolant. Arkenstone connectivity failure over Christmas that contributed to a small accident — I submitted 7 documented troubleshooting videos, YouTube analytics confirm 6 were never watched. Missing homologation kit hardware. Faulty chain adjuster. Screen protector shipped folded in half. Seat deformed under a cover at 70°F — warranty denied. And now an active, unresolved drivetrain issue that is the reason for this post.
Of those seven issues, Stark resolved two by shipping inexpensive replacement parts. Everything else was denied, unresolved, or fixed through my own research and effort.
The drivetrain issue — here's where I need your help:
I'm experiencing a rhythmic, periodic vibration with a fixed cycle of approximately 3 seconds at all speeds above 45 mph. Severity: just short of teeth-rattling on smooth tarmac. I also notice inconsistent power delivery at steady throttle — the bike perceptibly accelerates and decelerates with the throttle held constant. A second rider has independently confirmed both symptoms.
On performing a gear oil change I found:
- Visible metallic buildup on the magnetic drain plug
- Grey/metallic oil rather than clean fluid
- No obvious gear tooth damage on visual inspection of the right engine cover
I have a background in engineering and computer science. I wrote a Python optical flow analysis script and applied it to ride footage from a body-worn Insta360 GO 3S capturing movement of a bike-mounted Insta360 X5. The script measures frame-to-frame camera displacement as a proxy for chassis vibration.
Results across two clips:
- 28-second sample: 8 vibration peaks, mean cycle interval 3.70 seconds
- 38-minute extended ride: 198 vibration peaks, mean cycle interval 3.03 seconds
- The cycle interval remains consistent regardless of speed, road surface, and throttle input
Video:
Stark's response:
Initial guidance was to bring the bike to a dealer — 155 miles away in Tallahassee. When I asked if Stark could pre-coordinate with the dealer before I committed to a 310-mile round trip, the recommendation reversed to "probably fine, just ride normally."
Most recently, after I shared the optical flow analysis, Stark attributed the vibration to knobby tyres on tarmac and stated the service would not be covered under warranty. This contradicts a previous written statement from Stark in a ticket that bearing damage found despite proper maintenance would be covered in full.
Tyres do not put metal in gear oil. A 3-second periodic vibration that doesn't change with speed is not a tyre characteristic. I've disputed this formally and requested a video call with their engineering team.
What I'm looking for:
- Has anyone else — particularly EX owners — experienced a similar periodic vibration or found metallic debris on the drain plug?
- Has anyone had success getting Stark to engage seriously on a drivetrain issue, and what worked?
- Any EX owners who have dealt with Florida Motorsports in Tallahassee for warranty work?
Happy to share the Python script and analysis methodology with anyone who wants it.
— C.W.
