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Discussion Starter #1
I am sure most of y'all read about me dropping the LT in a 0mph incident this past weekend. Since it was lying down on a fairly banked curve, it took Kent, myself and another passerby to lift it up. FWIW, the bike was down on the road for maybe 5-7 minutes before we got it back up and straight.

After that, I now feel the clutch engagement very different. Earlier, it used to (dis)engage very quickly when I was pulling it in. Now, I have to pull it all the way in. Also, when starting from a full stop, in 1st gear, it feels jerky.

Someone suggested that I might want to check for air in those lines. Other than that, I did not notice any other difference in the bike's handling for the 400+ miles that I rode it back home. I haven't ridden the bike after I got home on Saturday night.

Any other pointers???

 

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Does the clutch lever feel spongy? If you pump it several times does it feel more firm? How long ago was the fluid changed? At what level was the clutch fluid in the reservoir before the drop, and is it at the same level now? Any sign of leaking fluid? In your get-off during the drop, did your knee or foot whack the handlebar anywhere near the lever?
 

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Did you bleed the clutch circuit well? That is the most likely thing to happen when laying the bike over, also often the brakes will need bleeding. The front brake will often be useless after a drop, but will normally self cure after sitting overnight. Happened to me once.
 

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While LT'ing in Alaska in 2004 I met up with another LT rider who described a similar experience. He cured it by bungie cording the clutch lever closed overnight which allowed the air to exit the system.
 

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Discussion Starter #5
Yes. It feels spongy. I did not try to pump it several times to fix it, but it did get used a lot in the 400 miles till I reached home :p

Fluids haven't been changed in a while, but I did the check and top off about 2K miles back. I haven't checked the level after drop. No sign of any fluid leaks and I did not hit the handlebars as I got off either.

was said:
Does the clutch lever feel spongy? If you pump it several times does it feel more firm? How long ago was the fluid changed? At what level was the clutch fluid in the reservoir before the drop, and is it at the same level now? Any sign of leaking fluid? In your get-off during the drop, did your knee or foot whack the handlebar anywhere near the lever?
 

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Discussion Starter #6
I haven't bled the clutch lines yet, but I plan to do that if this doesn't cure itself.

dshealey said:
Did you bleed the clutch circuit well? That is the most likely thing to happen when laying the bike over, also often the brakes will need bleeding. The front brake will often be useless after a drop, but will normally self cure after sitting overnight. Happened to me once.
 

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Since there seems to have been several pairs of hands on your bike while right upping her I would also check the adjusting knob located where the clutch lever hinges. It is possible that it had be changed by one click and could account for the different feel.
 

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Exact same thing happened to me last year.

Dave Shealey and Mark Neblitt suggested the "leave the bike overnight thing"

In my case I tied the clutch lever down, bike on centerstand, at full right lock and left it for 8 hrs. Everything was fine after that. Reservoir does not need to be opened.

Others have done the same procedure but with the lever out. Some opinions on position of the piston, pulling the air into the reservoir after release of the lever if tied - who knows. It worked for me.

Let us know how it does for you.
 

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Discussion Starter #9
zippy_gg said:
Since there seems to have been several pairs of hands on your bike while right upping her I would also check the adjusting knob located where the clutch lever hinges. It is possible that it had be changed by one click and could account for the different feel.

Good point. But, I've already tried that :)
 

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Discussion Starter #10
bowlesj said:
Exact same thing happened to me last year.

Dave Shealey and Mark Neblitt suggested the "leave the bike overnight thing"

In my case I tied the clutch lever down, bike on centerstand, at full right lock and left it for 8 hrs. Everything was fine after that. Reservoir does not need to be opened.

Others have done the same procedure but with the lever out. Some opinions on position of the piston, pulling the air into the reservoir after release of the lever if tied - who knows. It worked for me.

Let us know how it does for you.

I am going to try this tonight to see if it helps fix the problem.
 

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jkersh1 said:
While LT'ing in Alaska in 2004 I met up with another LT rider who described a similar experience. He cured it by bungie cording the clutch lever closed overnight which allowed the air to exit the system.
This gets my vote. I'm not sure that it matters, but if it were me I would remove the reservoir cover and after strapping down the lever, I would syringe out most of the fluid thus reducing the pressure from above.
 

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When the bike is laying on it's side the fluid in the reservoir will wash to one side, and depending on fluid level may not cover the port in the bottom of the reservoir. Because the port is open to the atmosphere at this point, if the clutch lever is pulled in while uprighting the bike a large bubble of air will be injected into the system.

The good news is that the bubble will be located near the reservoir so it should eventually clear itself. If not, a clutch fluid bleed is necessary.

The same principal also applies to the brakes. The prevention is to try to keep a presence of mind (yeah, sure) if the bike is dropped and not touch either lever until it is fully righted.
 

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jkersh1 said:
While LT'ing in Alaska in 2004 I met up with another LT rider who described a similar experience. He cured it by bungie cording the clutch lever closed overnight which allowed the air to exit the system.
That makes no sense at all! The fluid can only return to the master cylinder reservoir when the clutch handle is let all the way out. When the clutch lever is pulled in, the return passage to the reservoir is completely blocked by the master cylinder piston, else you could not build up pressure to release the clutch! When the handle is all the way out, the hole between the reservoir and the master cylinder is open, and no pressure on the system. Air bubbles can slowly work their way up the line and back into the reservoir. After you pull the lever in a little the piston closes off this hole so that pressure can be built up to force the slave cylinder out. When the handle is in, the pressure is maintained in the system.

The only thing I can think of is that if pressure is held overnight, and any bubbles do work their way up the line, then when the pressure is released the bubbles are pushed back into the reservoir instead of just working their way up normally with the handle left out.
 

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Discussion Starter #14
Thanks to all the suggestions. I left the clutch lever pulled in and bungee tied for 24 hours. Now there's life in the clutch lever!! It seems to be back in action like before!!

Now, another thing that I noticed. I was in the garage early this morning around 5 AM to see how the clutch felt. In the quietness of the garage, I could hear a faint "pop" sound as I pulled the clutch in every time. It almost sounds like there is air trying to escape/leak somewhere.
 

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no it does not make sense, but...

dshealey said:
That makes no sense at all! The fluid can only return to the master cylinder reservoir when the clutch handle is let all the way out. When the clutch lever is pulled in, the return passage to the reservoir is completely blocked by the master cylinder piston, else you could not build up pressure to release the clutch! When the handle is all the way out, the hole between the reservoir and the master cylinder is open, and no pressure on the system. Air bubbles can slowly work their way up the line and back into the reservoir. After you pull the lever in a little the piston closes off this hole so that pressure can be built up to force the slave cylinder out. When the handle is in, the pressure is maintained in the system.

The only thing I can think of is that if pressure is held overnight, and any bubbles do work their way up the line, then when the pressure is released the bubbles are pushed back into the reservoir instead of just working their way up normally with the handle left out.
I have to do the same thing to the front brake on my KTM. Bunge the lever overnight and magic. Don't ask me, but it does work.
 
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