Calling all bike mechanics. Need help diagnosing a clutch problem.

[drewvanracer]

My 2007 was in a bad accident and was rebuilt as my monster, Frankenstein (Frankie).
I added a cheap set of aftermarket handlebar clutch and brake hardware. After the build the clutch kept requiring longer and longer lever travel for the first year. Last year the bikes clutch would drag a stoplights. Now it is dragging so bad it is not ridable. I have never felt the clutch slip when accelerating including drag racing the bike. I then started replacing parts.

Bleed the clutch, no help.
Replaced the clutch master cylinder, no help.
Rebuilt the clutch slave cylinder, no help.
Replace the clutch hydraulic line, no help.
Pulled clutch plates and soaked for three days, no help.
Installed the original clutch master cylinder, no help.
Next is to install a $350 slipper clutch. I’ll be pissed if that does not fix it.

What am I missing?

[Dan Cooper]

My 2007 was in a bad accident and was rebuilt as my monster, Frankenstein (Frankie).
I added a cheap set of aftermarket handlebar clutch and brake hardware. After the build the clutch kept requiring longer and longer lever travel for the first year. Last year the bikes clutch would drag a stoplights. Now it is dragging so bad it is not ridable. I have never felt the clutch slip when accelerating including drag racing the bike. I then started replacing parts.

Bleed the clutch, no help.
Replaced the clutch master cylinder, no help.
Rebuilt the clutch slave cylinder, no help.
Replace the clutch hydraulic line, no help.
Pulled clutch plates and soaked for three days, no help.
Installed the original clutch master cylinder, no help.
Next is to install a $350 slipper clutch. I’ll be pissed if that does not fix it.

What am I missing?

The little brass bushing in the clutch lever.

dan

[Festus]

Or the ball bearing at the end of the shaft?

[drewvanracer]

My 2007 was in a bad accident and was rebuilt as my monster, Frankenstein (Frankie).
I added a cheap set of aftermarket handlebar clutch and brake hardware. After the build the clutch kept requiring longer and longer lever travel for the first year. Last year the bikes clutch would drag a stoplights. Now it is dragging so bad it is not ridable. I have never felt the clutch slip when accelerating including drag racing the bike. I then started replacing parts.

Bleed the clutch, no help.
Replaced the clutch master cylinder, no help.
Rebuilt the clutch slave cylinder, no help.
Replace the clutch hydraulic line, no help.
Pulled clutch plates and soaked for three days, no help.
Installed the original clutch master cylinder, no help.
Next is to install a $350 slipper clutch. I’ll be pissed if that does not fix it.

What am I missing?

The little brass bushing in the clutch lever.

dan

Nope, the brass bushing is in the lever.

[drewvanracer]

Or the ball bearing at the end of the shaft?

That's a good question. The clutch side cover comes off easily so I will have to verify my ball is at the end of the push rod.
Thanks

[Boston]

The plunger shaft will punch a hole right through the brass bushing. You should take the brass out and have a look. Or you might see the plunger shaft sticking out the other side. To get you by in a pinch you can rotate the brass 180. If it has not gone all the way through. $0.02

[raYzerman]

Physically, in the clutch (plates, pressure plate, etc.) there shouldn't be much wrong with it..... might wanna check the thickness of the plates next time you're in there, and check for the ball bearing (although I'd think you'd have more problems than that if it was missing). In the slipper clutch, there is one plate you can get that is thicker, so if your plates are a wee bit worn, you could tune it up with that....

The brass bushing in the lever is the key, since you've done everything else. Could be scored, worn oval, worn through.... all of which will cause problems. As well, if you have fresh fluid, tie the lever to the bar overnight and see if that firms up the lever.

New bushing you can get from any bike, all the same and cost more than they're worth, lol.

[N4HHE]

Aftermarket clutch and brake hardware?

The displacement of the master cylinder varies by motorcycle model. A long throw suggests your master cylinder piston may be too small.

[Bounce]

Nope, the brass bushing is in the lever.

Are the OD or ID worn out out-of-round? Cleaned and lubed annually?

[drewvanracer]

Thanks for all the post on this.
I checked all the suggestions and everything looks good on my bike.
My plan is to put my 2004 and 2007 side by side and start swapping parts this weekend.
I will keep you updated on what fixes the problem.
Drew

Update: I put the 2004 and 2007 side by side and pulled the clutch covers. I then measured the amount of movement between the pressure plate and the clutch basket when I fully pulled in the clutch lever. The 2004 with the working clutch moved 2.1mm and the gears were fully disengaged. The 2007 with the bad clutch moved 2.6mm and the clutch was still heavily dragging but I could move the plates in the basket, WTF. Pulled the clutch on the 2007 and everything measured with in spec. and the hub and basket looked great. I pulled the clutch on the 2004 but found out it will not fit the 2007 bike. After lubing the 2007 clutch plates I put it back together. I was still as bad as ever.
My plan is to purchase a complete used clutch assembly off of eBay and install, I will let you know.

[raYzerman]

Clutches no different, except.... Gen1 had a larger bore slave and took more lever travel... Gen2 has a smaller diameter and takes less travel, but the effort increased. Gen3 I believe returned to the larger bore. The slipper reduced the effort by ~20-25% by all reports.

I don't know your mileage..... However, if you're going into the clutch itself, check the outer clutch basket, and see if there are any notches where the tabs of the friction plates ride. If there are, then a friction plate tab may hang up and not fully release or engage.... if not severe, this notching can be filed smooth.

If you've been slowly losing lever travel over years (and not sporadically), check the thickness of the friction plates and see if you're at minimum. If so, get new friction plates...... or, there is one plate that comes in three thicknesses, get the thick one. Also consider buying a new pressure plate spring.

[drewvanracer]

UPDATE:
Purchased a complete used slipper clutch from a 2017 and have installed it this weekend. I did not install the outside basket because it is the same as my 2007 clutch basket. (thanks TwoWheelObsession.) WORKS GREAT. After the install, I replaced with the stock master cylinder with the aftermarket clutch hydraulic master cylinder that was installed before and it still worked great. The new clutch has 1/2 the clutch pull and still lifts the front end at will in the first two gears.
My original clutch never slipped, but would not disengaged from the engine making stop lights downtown very difficult. I am afraid of the same thing happening again in the next year or two but going to enjoy it for now.
Thanks for all the suggestions.
Pictures of Frankie to follow.
Drew

[extrememarine]

Excellent - glad it's sorted out.