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Discussion Starter #1
2000 Suzuki Hayabusa

Extensive mod list including:
Brock's Clutch Mod
Vortex 16T front sprocket
(Front sprocket, OEM rear sprocket, and EK chain all replaced a couple of thousand miles ago)
/end

So, I bought this bike about 3 years ago with 4700 miles on it, it now currently has almost 11,500 and I've been dealing with this the entire time.
Before Brock's clutch mod:
If I were to let the clutch slip out sort of higher, say 4000+ rpm, the bike would jutter real bad, like the clutch was gripping/slipping/gripping/slipping/gripping and if it was on the edge of 4000rpm it would make this wrrrrrrrrrrrrr noise until the clutch lever was fully released at which point it would go away and ride normally. I don't race this bike so as long as I kept the RPMs below 4000 when setting off from a stop I was perfectly fine. The higher the RPM would go though, the more violent the jutter would be.

After Brock's clutch mod:
Exact same thing, but it went from happening at 4000+ rpm and got worse and started happening around 2500-2800+ rpm. The wrrrrrrrrr noise is still there when slipping it at the edge of where it wants to jutter and all. What I've noticed now though is sometimes it does it at 2800rpm, sometimes it does it damn near off idle.

Inspection:
Before I did the Brock's clutch mod, I took all the fibers and steels out to visually inspect them, the basket, and the pressure plate (All of which appear to be factory OEM). There is no real bad heat scoring to note, the fibers are all in great shape, pressure plate and basket surface looked fine, fingers on the basket are in good shape (I don't have the tools to measure any of this, I was just looking for anything that was out of the norm). Took a caliper to each of the fibers and steels and measured them, they all measured to pretty much new spec and the stack height is perfect. I put everything back together in order as the service manual states. I did soak the fibers for 24 hours in new oil which I later found out Brock's recommends against that due to possible swelling of the fibers and increased stack height. It made no difference at the time, clutch felt the same before and after.

Video:
I slapped together a quick video in an attempt to capture the wrrrrrr sound and the juttering. As I stated, the higher the RPM the worse it gets. It feels like the clutch is slipping and gripping very quickly making it very jerky.


My thoughts:
Because this is something that only happens when I'm touching the clutch lever, I have to think it's inside the basket itself, otherwise I feel it would give some sort of symptom at all times while riding. I want to say this is an issue with the steels/fibers, or maybe the pressure plate or surface of the basket where the first fiber goes, something... But I'm open to any/all ideas at this point.
 

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Do you like that aggravation on such a low mile bike when you don't even drag race?
I would yank that shit out of there and go back to stock so fast...
 

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Pull it all out and have a look. It's a whole lot easier to diagnose a clutch problem when the clutch is on a bench.

Sent from my SM-G975U using Tapatalk
 

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2000 Suzuki Hayabusa

Extensive mod list including:
Brock's Clutch Mod
Vortex 16T front sprocket
(Front sprocket, OEM rear sprocket, and EK chain all replaced a couple of thousand miles ago)
/end

So, I bought this bike about 3 years ago with 4700 miles on it, it now currently has almost 11,500 and I've been dealing with this the entire time.
Before Brock's clutch mod:
If I were to let the clutch slip out sort of higher, say 4000+ rpm, the bike would jutter real bad, like the clutch was gripping/slipping/gripping/slipping/gripping and if it was on the edge of 4000rpm it would make this wrrrrrrrrrrrrr noise until the clutch lever was fully released at which point it would go away and ride normally. I don't race this bike so as long as I kept the RPMs below 4000 when setting off from a stop I was perfectly fine. The higher the RPM would go though, the more violent the jutter would be.

After Brock's clutch mod:
Exact same thing, but it went from happening at 4000+ rpm and got worse and started happening around 2500-2800+ rpm. The wrrrrrrrrr noise is still there when slipping it at the edge of where it wants to jutter and all. What I've noticed now though is sometimes it does it at 2800rpm, sometimes it does it damn near off idle.

Inspection:
Before I did the Brock's clutch mod, I took all the fibers and steels out to visually inspect them, the basket, and the pressure plate (All of which appear to be factory OEM). There is no real bad heat scoring to note, the fibers are all in great shape, pressure plate and basket surface looked fine, fingers on the basket are in good shape (I don't have the tools to measure any of this, I was just looking for anything that was out of the norm). Took a caliper to each of the fibers and steels and measured them, they all measured to pretty much new spec and the stack height is perfect. I put everything back together in order as the service manual states. I did soak the fibers for 24 hours in new oil which I later found out Brock's recommends against that due to possible swelling of the fibers and increased stack height. It made no difference at the time, clutch felt the same before and after.

Video:
I slapped together a quick video in an attempt to capture the wrrrrrr sound and the juttering. As I stated, the higher the RPM the worse it gets. It feels like the clutch is slipping and gripping very quickly making it very jerky.


My thoughts:
Because this is something that only happens when I'm touching the clutch lever, I have to think it's inside the basket itself, otherwise I feel it would give some sort of symptom at all times while riding. I want to say this is an issue with the steels/fibers, or maybe the pressure plate or surface of the basket where the first fiber goes, something... But I'm open to any/all ideas at this point.
Juddering like that makes me think pieces are warped. I know you said this problem happened before the mod. Did you try a new set of steels and frictions?

They all may measure like they should in one spot, but are they actually flat all the way around? You could pull it all apart and lay the steels on a piece of glass to see if they wobble or not. But honestly if it were my bike I'd have order all new oe clutch pack.

If you are not the only person to have owned the bike check in the shop manual and make sure all the pieces taken out are oriented correctly. Good luck.
 
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