First XS650 Build, What to Look For

Ditto with 5twins. Here's a pressure plate travel thread:

http://www.xs650.com/threads/clutch-pressure-plate-travel.48508/

You can put the trans in 5th gear, and move the rear wheel while observing clutch action, see what it takes to release. Your friction plates have a dark color, like they were overheated at some time, which can make cork composition plates sticky, difficult to release. You can remove some of the sticky glazing by light sanding the plates on a flat surface. Otherwise, looks like you're experiencing the common "stuck clutch" syndrome.

Some insights in these:

http://www.xs650.com/threads/yamaha-xs650-experimental-clutch.47498/

http://www.xs650.com/threads/finding-neutral-while-stopped-and-in-gear.47568/
 
Haha, I see.

Question for you, what will doing this hopefully show? I've spoken with a few folks offline who mentioned that the plates are functioning normally, and don't always move in unison.

So I'm a bit lost as to what's happening. Hopefully the kicking with the clutch pulled will help show the problem, but as I've mentioned before the bike tries to move forward when I kick with the clutch pulled in. So something is causing the clutch the stick and not disengage, even with a ton of extra separation at the plate.
 
All the kicking does is show you whether the clutch is disengaging or stuck engaged (not releasing). Yours appears to be stuck but I don't know why. The parts look like they're moving as they should in your videos.
 
... the bike tries to move forward when I kick with the clutch pulled in. ..

Huh? Are you kicking it while it's in gear?

Can't do that on an XS650.

Must be in neutral to do the kickstart.


However, if you ARE in neutral, and the kickstart tries to rotate the rear wheel, this has now become a transmission problem...
 
Sorry I should have been more clear about that. I was referring to the testing method of putting the engine into 1st gear, pulling the clutch in and kicking it to see if it moves or not. In my case, it does move. This tells me the clutch is sticking.

As far as WHY it's sticking or HOW to fix the sticking, I have less ideas lol.

I'm wondering if new clutch plates are in order or would be helpful in this situation. I'll try removing the clutch plates altogether, putting it in first and kicking it. If the kicker slides through without moving the bike, then the plates are the problem. If the bike moves forward even without the plates, then I'm in even worse shape than I thought, but the plates are not the culprit.
 
You can't kickstart while it's in gear!

The kickstarter uses the transmission's 1st gearset to drive the clutch. You could completely remove the clutch assembly, and, if in gear, kickstarting WILL rotate the drive sprocket.

Do all your kickstarting while in neutral, ONLY....
 
Really? I'm almost positive that was a test procedure someone in this thread mentioned I should try.

Good to know though, I will skip that test and see if I can rock the bike back and forth to free up the clutch with it in first gear and the clutch pulled.
 
What a lot of us do is:

Put trans in neutral.
Pull-in the clutch lever.
Kick until the kicker swings free.
That unsticks the clutch.
Let out the clutch lever.
Kickstart the engine.
Drop it into 1st.
Terrorize the neighborhood...
 
It's normal for these bikes to be hard to push around in gear with the clutch pulled, or stepped on in your case. It's just the nature of this beast. There's lots of clutch drag.
 
Haha, I see.
Question for you, what will doing this hopefully show? I've spoken with a few folks offline who mentioned that the plates are functioning normally, and don't always move in unison.
So I'm a bit lost as to what's happening. Hopefully the kicking with the clutch pulled will help show the problem, but as I've mentioned before the bike tries to move forward when I kick with the clutch pulled in. So something is causing the clutch the stick and not disengage, even with a ton of extra separation at the plate.
Hi SM,
my perversion is different to yours; I left my controls alone but hung a sidecar on it.
This lets me check stuff without the bike falling over or in need of a helper to hold it up.
Bike in neutral, pull the clutch, the clutch slips when you kick it over.
Bike in ANY gear, pull the clutch, the clutch still slips on kickover but the bike moves along.
What dismantling the clutch one layer at a time and kicking it over will show is WTF is happening with it.
If (for instance) all the plates are removed the kicker CAN'T turn the engine over but if the transmission
ain't in neutral even if it thinks it is, the bike will still move along when it's kicked.
 
Thanks for the tips and the vote of confidence, I did have a chance to spend another night with the bike and got some good signs.

I took the plates out and sanded them on some 400 grit sandpaper taped to the flat garage floor. I sanded both sides of each plate and each metal plate as well.

After reinstalling them (but not torquing them to spec) I put the bike in first and pressed the clutch in and she rolled back and forth easily! Great news. At least I know nothing is binding up in there. Small victory but I'll take it.

Next I torqued them to spec with my torque wrench (7ft lbs). Now my torque wrench seems to put these bolts on WAY tighter than 7ftlbs. Idk why that is, maybe the springs alter the pressure reading? But I know that 7ft lbs is about hand tight plus another 1/8-1/4 of a turn. So I did that by hand and tried again. First gear, clutch pulled, bike doesn't roll smoothly but after pushing it back and forth a few times it does spin the basket freely and roll. Problem is, once I let go of the clutch and press it in again, same boat.

Here's what I want to try tonight when I go back over there.

I'll take the bike over to the slight hill by the garage, fire it up, get her rolling and drop her into second gear and see if I can get it to move under it's own power. From there, I believe pressing and releasing the clutch is the best way to go. Ride around for a bit and see if I can get it to wear down to where I don't have to do a running start to get her into gear and can actually sit in neutral with the engine running and shift it into first like a civilized human being lol.

More updates to come. Thanks for sticking with me guys.
 
Hi SM,
about torque wrenches, they are only accurate in the middle (~ 65%) of their range.
If your torque wrench is OK to set the 100+ ft/lbs needed for the larger fasteners
the 7 ft/lb setting will be right at the bottom of it's range and most likely won't be accurate.
 
You should have seen how long I sat with the two torque wrenches in my cart at checkout before deciding which I was more likely to need lol.

For the time being, I went with finger tight plus a quarter turn. Snug.
 
Alright guys, so I swung by the garage yesterday to see if I could get the clutch freed up and here's what I found.

I took the bike to the top of a slight hill, fired it up, got a good running start and dropped it into first and off I went! My god is this bike quick off the line. I guess that's to be expected with the 700 overbore and the fact that I've taken almost everything off of it besides what makes it go. Really tries to dump me off the back if I get on the throttle quickly! Took her for a spin on some backroads near my parents place (very few other cars or stop lights) and got her all the way up to fifth gear. What a rush! I can't believe it's finally at a point where the bike I found rotting in a backyard is now flying me down the street at 50+mph.

Ok, enough of the swooning. Let's talk about the clutch. With the bike in first and cruising, if I pull the clutch in it takes about a second for the plates to free up. You can hear it distinctly when they free up. It's like a rubbing noise, the same that I heard when I was pushing it back and forth with the clutch in in first gear in the driveway. So the process for shifting is the pull the clutch, wait a second or two for the disengagement, then shifting is easy. It goes between all gears smoothly once the plates separate.

That being said, stopping is not viable currently. I'm not sure what the exact issue is, but if I put her in neutral and being to slow down, I have to blip the throttle or she'll die out. This could be carb related, I did bend that tab over the float so maybe that's causing it? I'll have to pull that off next time I'm in the carb. I do suppose it could also be capacitor related, but the bike will idle after kickstarting and not die, so I'm thinking it's got something to do with the vacuum that occurs under deceleration. Again, seems like a carb issue. This is also more evident when rolling on throttle from idle. It tends to stutter and lag noticeably when speeding up (pilot and needle position circuits) whereas wide open throttle has no issues.

With regard to the manifold, I don't suspect any air leaks as there is no wandering idle when blipping the throttle nor is there any popping on deceleration. Just a sticky clutch and perhaps the wrong pilot jet?

Either way though, not sure what else can be done about these clutch plates, if that didn't unstick them I can't think of anything that would. Suggestions appreciated.

Thanks!

JHFWLwj.jpg
 
The slots in your main clutch hub that the friction plate tabs slide in may be all notched up. They look pretty bad in one of your videos. That can cause the plates to hang or stick. You can file the slots a little to smooth them out but I guess removing too much material is no good either. That makes the slots too wide. I'm not sure exactly what that does to the clutch operation but I guess it's not good. It may come down to having to replace it. If you're patient, you can often find whole clutch assemblies on eBay for about $30. If you go that route, I would recommend getting the '80 and later 6 plate unit, they work/engage smoother.
 
You should have seen how long I sat with the two torque wrenches in my cart at checkout before deciding which I was more likely to need lol.
For the time being, I went with finger tight plus a quarter turn. Snug.

Hi SM,
the sad reality is, you need two of them to get the torque ranges the bike's fasteners need in the accurate middle part of their settings.
One for the big bolts and another for the little bolts.
Nice looking baby blue chopper BTW. Pity that some death-wishing dimwit has removed it's front brake.
 
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