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Splines were good on this replacement coupler? Splines on the final drive are ok?

Any debris in the oil screen when you pulled it? A lot of clutch material might point to worn clutch discs. The recent antifreeze in the oil might have taken it out too. Then of course, it needs the correct oil for the wet clutch.

Chance it may be the clutch is worn out, or it's stuck. Coffee Grinder Syndrome is often a problem on this bike, many discussions on it. It happens when the clutch doesn't grab when you let the lever out, then grabs suddenly and unexpectedly.

I suppose it's possible the clutch pack could just stick in the released position and stay there. But if the clutch lever has spring action when you move it, then it's not likely stuck.
 

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I had the same/similar issue a few months back. I checked both the Clymer and Haynes manuals for how to adjust the cable but still needed some help from here (Thx Spockster).
Is that gap lined up for the clutch arm with the line on the engine case? I had to take it off and realign it to get the cable adjustment right.
Worth mentioning before you rip the clutch basket out.
 

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Discussion Starter #23
Yes- splines weren't worn on either of the replacement parts. I do not have any history on the clutch discs, or any experience to know by looking if they're worn out of not. Clutch does have a spring action.

All seems really bizarre to me. I'm going to check the oil screen before I pull the plug to repack the clutch, but otherwise it can't hurt anything to do so.

Splines were good on this replacement coupler? Splines on the final drive are ok?

Any debris in the oil screen when you pulled it? A lot of clutch material might point to worn clutch discs. The recent antifreeze in the oil might have taken it out too. Then of course, it needs the correct oil for the wet clutch.

Chance it may be the clutch is worn out, or it's stuck. Coffee Grinder Syndrome is often a problem on this bike, many discussions on it. It happens when the clutch doesn't grab when you let the lever out, then grabs suddenly and unexpectedly.

I suppose it's possible the clutch pack could just stick in the released position and stay there. But if the clutch lever has spring action when you move it, then it's not likely stuck.
 

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Discussion Starter #24
The gap was previously not aligned close, but I just aligned it when I attempted to take it for a test ride. Didn't yield any different results though. I was hopeful it might haha.

I had the same/similar issue a few months back. I checked both the Clymer and Haynes manuals for how to adjust the cable but still needed some help from here (Thx Spockster).
Is that gap lined up for the clutch arm with the line on the engine case? I had to take it off and realign it to get the cable adjustment right.
Worth mentioning before you rip the clutch basket out.
 

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If you don't mind taking the rear wheel off again, you can just look and see if the drive shaft is spinning when it's in gear.
Come to think of it, there's a rubber gasket at the swing arm where the drive shaft connects to the transmission. You can just pull that back with a screwdriver and see if the shaft is spinning without really disassembling anything. That would at least point you towards the right half of the drive train.
 

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Discussion Starter #26
I didnt even think of that. Would you recommend firing up the engine while the rear wheel is off to see the driveshaft spin? Or would that do damage?

If you don't mind taking the rear wheel off again, you can just look and see if the drive shaft is spinning when it's in gear.
Come to think of it, there's a rubber gasket at the swing arm where the drive shaft connects to the transmission. You can just pull that back with a screwdriver and see if the shaft is spinning without really disassembling anything. That would at least point you towards the right half of the drive train.
 

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I would think if the clutch plates where worn badly (but clutch otherwise seems to work) you would feel some resistance from the clutch plates.

I would have to think either the clutch assembly is not closing the gap between plates and disks (thats done by springs). that would be stuck pressure plate or all the springs broken/bad (all 5 of them?)

or the driveshaft is not connected properly to the splines at the front bevel, or the splines at the rear bevel are bad/not engaging the rear bevel. There is a spring that goes inside the coupler that will push the shaft to the front of bike to keep the front splines engaged

there is possibility of something in the transmission being fubar, but thats not common on these
 

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I would think if the clutch plates where worn badly (but clutch otherwise seems to work) you would feel some resistance from the clutch plates.

I would have to think either the clutch assembly is not closing the gap between plates and disks (thats done by springs). that would be stuck pressure plate or all the springs broken/bad (all 5 of them?)

or the driveshaft is not connected properly to the splines at the front bevel, or the splines at the rear bevel are bad/not engaging the rear bevel. There is a spring that goes inside the coupler that will push the shaft to the front of bike to keep the front splines engaged

there is possibility of something in the transmission being fubar, but thats not common on these
Good points. Second paragraph made me think of a broken clutch basket. Lever has spring action, but flexing of the basket prevents engagement?

Important 3rd paragraph - Coupler spring is in place, or missing? Previous owners might have been in there, sounds like you had some old grease on worn rusty splines.

New clutch plates have friction material approx. the thickness of 2-3 layers of cereal box. Plates that are worn put can have thickness of of one layer, but they can still move the bike, probably slipping when power is added.

If nothing MTB posted is amiss, your plates must be completely wiped smooth. However, I'm reminded of a bad clutch I had one miserable winter. I could start the car, put it in gear, get out to scrape the windows with the trans in gear, get back in to rev the engine. After a while the car would move and drive although the clutch slipped if I put on too much power. Drove to work a week this way. So even metal to metal, a clutch can still grab.

Does it look like the clutch has been opened up, like a new gasket, etc.? Somebody left a disc or steel out?
 

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I didnt even think of that. Would you recommend firing up the engine while the rear wheel is off to see the driveshaft spin? Or would that do damage?
Thinking on it more, I'd leave the tire on. An unsupported shaft could flop and shift and bang around horribly. Looking past that rubber gasket at the transmission should be fine on the center stand started in neutral then clutch released in 1st.
 

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Discussion Starter #30
Thanks for the info. The clutch pack is good and I soaked it overnight in a good oil. Put everything back together and still no deal.

Heres how this happened originally. The bike was running perfectly normal, then I pulled in the clutch while in 1st, and then the bike wouldnt move as it still does not.

Clutch cable tension has been adjusted as per the manual. The only possible thing could be the rear driveshaft coupler, however that looks in very good condition.
I would think if the clutch plates where worn badly (but clutch otherwise seems to work) you would feel some resistance from the clutch plates.

I would have to think either the clutch assembly is not closing the gap between plates and disks (thats done by springs). that would be stuck pressure plate or all the springs broken/bad (all 5 of them?)

or the driveshaft is not connected properly to the splines at the front bevel, or the splines at the rear bevel are bad/not engaging the rear bevel. There is a spring that goes inside the coupler that will push the shaft to the front of bike to keep the front splines engaged

there is possibility of something in the transmission being fubar, but thats not common on these
 

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You might pull the clutch cover and observe the clutch pack while moving the lever, but with the spring action I'm not sure it would show anything. It seems that it all should be moving, if it was broken or stuck, the hand lever should feel dead.

Yes, the driveshaft will flop around with the rear drive removed, it lays down against the swingarm tube when the gear is not installed. There's just nothing else holding it up.

Only part not checked is the bevel gear. There are dogs in there that lock up, with a spring to hold tension. With the bevel case removed, you should be able to rotate the driveshaft and see if the rear coupler and rear gear are engaged, or just spin the rear wheel by hand. Could be the front splines, but I've never heard of it.

Haven't heard of the trans breaking, but it's not impossible. I do recall some having troubles at the bevel gear, but don't recall exactly what. Broken dogs or shredded gears maybe. One poster did have the cover and seal pop off, he bought a can of soup and hammered the can in there to get home.
 

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Discussion Starter #32
The one thing I noticed with the clutch basket while packing it was that it spun freely (the bike was in neutral at this time) and I could not torque the spring bolts without putting it into 1st gear. I'm confident there are the right number of plates, etc.

I just took a peek under the rubber seal near the transmission, and the front splines appear the same while the bike is in neutral and 1st. It does seem that the problem lies in the engine.

When I replaced my head gaskets, I never pulled off the front bevel gear housing. I do know that the clutch pushrod is free and in good shape though.

I had the bike just in 1st gear on the centerstand, and with the clutch handle fully out, if I spun the rear wheel BACKWARDS with my foot, the wheel would sort of tick and slow itself dowm. That led me to believe that there is a little power being transferred in the engine?

Thanks for your continued help. The weather is finally nice here and I want to get riding!

You might pull the clutch cover and observe the clutch pack while moving the lever, but with the spring action I'm not sure it would show anything. It seems that it all should be moving, if it was broken or stuck, the hand lever should feel dead.

Yes, the driveshaft will flop around with the rear drive removed, it lays down against the swingarm tube when the gear is not installed. There's just nothing else holding it up.

Only part not checked is the bevel gear. There are dogs in there that lock up, with a spring to hold tension. With the bevel case removed, you should be able to rotate the driveshaft and see if the rear coupler and rear gear are engaged, or just spin the rear wheel by hand. Could be the front splines, but I've never heard of it.

Haven't heard of the trans breaking, but it's not impossible. I do recall some having troubles at the bevel gear, but don't recall exactly what. Broken dogs or shredded gears maybe. One poster did have the cover and seal pop off, he bought a can of soup and hammered the can in there to get home.
 

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Discussion Starter #33
The spring IS in place. The clutch plates i'd say have the thickness of between 1-2 layers, so not brand new.

Good points. Second paragraph made me think of a broken clutch basket. Lever has spring action, but flexing of the basket prevents engagement?

Important 3rd paragraph - Coupler spring is in place, or missing? Previous owners might have been in there, sounds like you had some old grease on worn rusty splines.

New clutch plates have friction material approx. the thickness of 2-3 layers of cereal box. Plates that are worn put can have thickness of of one layer, but they can still move the bike, probably slipping when power is added.

If nothing MTB posted is amiss, your plates must be completely wiped smooth. However, I'm reminded of a bad clutch I had one miserable winter. I could start the car, put it in gear, get out to scrape the windows with the trans in gear, get back in to rev the engine. After a while the car would move and drive although the clutch slipped if I put on too much power. Drove to work a week this way. So even metal to metal, a clutch can still grab.

Does it look like the clutch has been opened up, like a new gasket, etc.? Somebody left a disc or steel out?
 

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Discussion Starter #34
Just checked this out- the bike seems to behave the same way in neutral and 1st gear.

Thinking on it more, I'd leave the tire on. An unsupported shaft could flop and shift and bang around horribly. Looking past that rubber gasket at the transmission should be fine on the center stand started in neutral then clutch released in 1st.
 

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The one thing I noticed with the clutch basket while packing it was that it spun freely (the bike was in neutral at this time) and I could not torque the spring bolts without putting it into 1st gear. I'm confident there are the right number of plates, etc.

....
Makes me think there's a problem with one of the gears behind the clutch case. There's an idler gear in there, someone did have a problem with that.

The clutch should be locked to the engine via those gears. Right guys?
 

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Discussion Starter #36
Spockster- that was my understanding too, that the clutch basket shouldn't move. Looks like I should pull that side of the frame off and pop the cover?

Makes me think there's a problem with one of the gears behind the clutch case. There's an idler gear in there, someone did have a problem with that.

The clutch should be locked to the engine via those gears. Right guys?
 

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Spockster- that was my understanding too, that the clutch basket shouldn't move. Looks like I should pull that side of the frame off and pop the cover?
It's looking like you should check.

Just to be sure... The clutch would move with a wrench, but you would feel the engine rolling up onto the compression stroke for each cylinder. "Spinning freely" sounds like that doesn't happen.

Going to look through the manual, but I'm pretty sure there's a gear connecting the clutch and crankshaft, versus the clutch being on the end of the crank.

Edit: Section 5-9, bottom right pic, there's the gear on the crank ahead of the clutch.

Edit: Found a pic

 

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Discussion Starter #38
Yes, what you described is not happening. The clutch spins like a fan would.

I'll have to dig in then. I just noticed a rattling sound coming from that side of the engine, seeming like it was a nut that spun off. At that point I killed the engine.

Thanks so much.

It's looking like you should check.

Just to be sure... The clutch would move with a wrench, but you would feel the engine rolling up onto the compression stroke for each cylinder. "Spinning freely" sounds like that doesn't happen.

Going to look through the manual, but I'm pretty sure there's a gear connecting the clutch and crankshaft, versus the clutch being on the end of the crank.

Edit: Section 5-9, bottom right pic, there's the gear on the crank ahead of the clutch.
 

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Yes, what you described is not happening. The clutch spins like a fan would.

I'll have to dig in then. I just noticed a rattling sound coming from that side of the engine, seeming like it was a nut that spun off. At that point I killed the engine.

Thanks so much.
Pretty sure someone had a broken bolt on that crank gear. Edited in a pic below.

You're welcome. Hope you get there.
 

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With the clutch cover off, you could spin the back wheel to see if the driveshaft is connected, since the clutch seems to be disconnected from the engine. In gear, the clutch would spin with the back wheel.
 
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