So while I'm waiting on parts for my HQ 103 build, I pull my primary to install a SE compensator and a stiffer clutch spring. I see some metallic particles on the clutch hub as I pull everything out. Turns out the splines on the clutch hub are damaged, but only the first 3/8" or so. I bought the bike new and no one's been in the primary except the dealer. They replaced the stator under warranty. The damage appears to have been caused by mis alignment of the clutch during reassembly. Can someone with more experience tell me what else might have caused this kind of damage?

 

Deleted, due to incorrect explanation on what controls how far the hub sits on the shaft.
Ron

 

Yea all the teeth were damaged, I knocked the rest of them off with my finger! Since they were all held in place until I removed the hub I guess it would make sence that the hub was pushed on too far and the ends of the splines were damaged as they were forced into the tapered part of the main shaft.

 

Something just don't look right in the pics, at least compared to my 07. I need to inspect some of my old parts to see what it is.
Just checked and I was wrong in the first post. The depth that the hub can go on is controlled at the nut end by hitting the end of the shaft with an internal stop. Your pic does not show that the splines tried to climb the ramp and seems normal. Wear marks show full contact over the length, maybe a touch tighter toward the broken teeth area. . Early on it may have shown this with a different wear point, but over time after the teeth were cracked it used the whole spline. All you can do is check everything out carefully when you install it to find out how it fits.
Ron

 

I do not think the hub can go on the shaft too far back because of the front of the hub touching the end of the shaft. Looking at your shaft in the pic it does not appear that anything went up to the ramp on the shafts splines.

 

Isn't that strange. Pulled mine apart this last week to install SE comp and Evo Industies 49T and found the same thing. Ones that weren't broke off just knocked off with screw driver, same depth of 3/8".

 

Mine were the same. The original pic is how it looked when I pulled it out. after that I was able to knock the remaining pieces off with my finger. Really not sure what would cause this.

 

I suspect the problem is with the piece of crap stock compensator. The weak spring washers in the stock unit allow ramp up too quickly and it bangs on the whole primary. I also believe this is what is causing the starter ring gear problems and starting kickback problem that I and many others have had. This shock has got to affect the clutch basket. All I know is that when I changed out the stock for the SE compensator all my primary noise banging stopped from starting and the bike rode smoother. This is just my opinion.

 

Glad I don't run a compensator. Just hints toward my theory being correct that compensators do more harm than good. JMO

 

Well, gave the matter some thought and the best I can come up with is the shaft has some torquing or torsional effect happening. When you think about it, that small dia shaft has no choice but twist and rebound at high loads. Since the spline area will remain rigid in the hub, the only place it can twist is right at the end between the start of the splines and the ipb. This might be enough to crack the teeth off in this area of flex since it will be the first area to see this torsional load.
Good thing the shaft is tougher than the hub or things could get really expensive. I checked my stock hub again and it shows no distress in that area. Then again the 96 may not have the poop, plus I've never done a flaming burnout with it either. Just put a Rivera clutch on and it has a new spined hub, so have to wait and see how that works out, especially now that the hp/torque have been increased. I wonder how may more have this condition and don't know about it?
Ron