Hard to Pull Clutch - Ideas? (2011)

Status
Not open for further replies.

Bonwit

Joined
Jul 20, 2009
Messages
217
Country flag
The clutch on my '74 850 is really hard to pull. Harder than normal, even for a Commando. Today I decided to try and find the problem. I knew the cable was not suspect since it's new. To rule out a routing problem, I detached the cable and ran it in a curving arc away from the bike and still had the problem. Then I decided to pull the clutch and check out the plates. The previous owner added new plates at some point, along with a belt drive conversion, but I don't know the brand. What I found was a set of 5 bronze colored pressure plates, 0.125" in thickness. The stack came within a 16th to 3/32 from being flush with the top of the basket. Someone told me that these bronze plates are not correct for a belt driven bike, since they were not intended to be run dry. Though the plates were not sticking together, I wonder if this could be my problem? Can anyone confirm for me if having these bronze plates might be an issue with a belt drive? Any advice on replacements?

Thanks
 
You can optimize as much as you want, but a Commando clutch with the concentric spring is a bear. They have hydraulic conversions for sale I understand.
 
I would not rule out the cable just because it's new. This is the kind of assumptions that leads to late nights in the shop with half the bike in pieces and later madness. Check everything from the lever on down through the transmission and out through the clutch rod. Everything matters from smooth cable routing to easy clutch rod operation.

I can't see how the thickness of your clutch plates or the type of plates you are running could cause the clutch pull action to bind up.
 
Hi!

The Commando clutch was designed to be have the plates dry. When the get oily, you can feel the clutch slip.

So, does not matter if one has a traditional chain with some oil to slop on it in the bottom of the primary, or if
one has a belt. Dry is dry.

Because you say you cable is routed properly, I would suspect that the lifting rod inside the great box has fallen.

If you take off the gear box inspection little cover and look in there, you will see where the end of the clutch cable
is attached to the end of the lifting rod. If is very important that the rod be in the right position before the
cable is attached to it. Your's be have been improperly put on a long time ago.

Commando clutches, when set up correctly, can have a nice light pull on them, mine is a two finger lever feel.

So, get your workshop manual out and read about how to make sure the clutch lifting arm is in the up position,
and has not fallen.

If you have never dealt with this before, see if you can find someone where you live, perhaps on this list. who
has experience setting your clutch up right. Your clutch pull should be very nice and smooth, and pretty easy!
 
montelatici said:
You can optimize as much as you want, but a Commando clutch with the concentric spring is a bear. They have hydraulic conversions for sale I understand.
Click to expand...

Strongly disagree! My Commando clutch with bronze plates is like butta!! Almost as easy to pull as the hydraulic clutch on my 96 Thunderbird. Tells me the standard Commando clutch can be set up to be very easy to pull. Now my Dominator, that's a different story!!
 
Bonwit
Your Clutch Pack stack height might not be correct. Check first. You need to oil your cable even if it’s new… if you haven’t done so. Also check your Gearbox Clutch Operating Lever # 33, 06-0715. Make sure it has not fallen down or is out of alignment with the cable entry. These should be looked at if you have difficult clutch pull at the lever. You should be able to pull your clutch lever with two fingers if set-up correctly.
Regards,
CNN
 
CanukNortonNut said:
Bonwit
Your Clutch Pack stack height might not be correct. Check first. You need to oil your cable even if it’s new… if you haven’t done so. Also check your Gearbox Clutch Operating Lever # 33, 06-0715. Make sure it has not fallen down or is out of alignment with the cable entry. These should be looked at if you have difficult clutch pull at the lever. You should be able to pull your clutch lever with two fingers if set-up correctly.
Regards,
CNN
Click to expand...

Two weak fingers.
 
swooshdave said:
CanukNortonNut said:
Bonwit
Your Clutch Pack stack height might not be correct. Check first. You need to oil your cable even if it’s new… if you haven’t done so. Also check your Gearbox Clutch Operating Lever # 33, 06-0715. Make sure it has not fallen down or is out of alignment with the cable entry. These should be looked at if you have difficult clutch pull at the lever. You should be able to pull your clutch lever with two fingers if set-up correctly.
Regards,
CNN
Click to expand...

Two weak fingers.
Click to expand...

Agreed. Two fingers. On a good day my old body can do it with one middle finger. Don't recall how I managed to get it to this point point, but if you go by the "tech digest" and experiment you'll get it. There is so much info out there on the clutch, it honestly surprises me that it's such a mystery. Keep trying, you'll get in.
 
In addition to what CanukNortonNut says, the locking ring at the clutch release arm can come loose disorienting the alignment to where the cable attaches to the arm.

Also, with the clutch pack assembled in the hub, check the distanct between the top off the clutch diaphram and the groove for the big snap ring. This distance should be around 30 to 50 thou. This picture shows way too much clearance and should be adjusted with an extra drive (steel)plate. In this state the diaphram has to be flexed up past it's center position to function. When positioned correctly the flex point is much closer to actuation and requires very little effort to work.
Hard to Pull Clutch - Ideas? (2011)
 
My clutch is not a 2 finger one, but not bad even for my aged hand muscles. If it is working right, you can feel the pressure plates break over their pressure and it becomes real easy to hold. Like everyone else says here, check the clutch op lever, if it is not right, you can ruin the cable in a hurry and the clutch operation is very strange and spongy. You also need to set the clutch rod with the adjuster nut, I usually make it a 1/4 or less turn off contact. You can feel this clearance straddling the bike, adjusting with the left and feeling the op rod/lever with the right. Tightening the lock nut will change the setting so it takes a few iterations, you want a very small amount of free play there. Check the clutch pack height, this is where mine is not optimal and could be improved. Mine has a small space before contacting the spring and if I reduced that space it would work lots better. Old Britts will sell you a bunch of spacers to try and then send the ones you don't use back for refund. Once those 3 items are correct, make sure the adjuster at the lever is set up correctly with the free play. That should be about it.

Dave
69S
 
Couldn't it be a worn Clutch Center? The plates could bind on the center causing a difficult, not-so-smooth pull.
 
Anglophile said:
Couldn't it be a worn Clutch Center? The plates could bind on the center causing a difficult, not-so-smooth pull.
Click to expand...

I don't think the notching will affect the pull feel. The spring will lift regardless of the plates. Unless they are severely stuck together.
 
Thanks for the helpful replies everyone. I checked everything you all suggested. Everything looks good except the clutch stack height. It's probably about .080 in. from being flush. This bike has a Norvil belt drive, and I see in their instructions where they suggest you add an additional plate, which apparently I don't have, and which is about that thickness. I just went ahead and ordered a new clutch pack from CNW. Hopefully, that will solve the problem.
 
Bonwit said:
Thanks for the helpful replies everyone. I checked everything you all suggested. Everything looks good except the clutch stack height. It's probably about .080 in. from being flush. This bike has a Norvil belt drive, and I see in their instructions where they suggest you add an additional plate, which apparently I don't have, and which is about that thickness. I just went ahead and ordered a new clutch pack from CNW. Hopefully, that will solve the problem.
Click to expand...
I really don't see how it would matter if it was a chain or belt in relation to clutch pull. Anyway, a fresh pack should resore pack height to spec. Being at .080, fresh stuff should add .030 to .040.
 
pvisseriii said:
Bonwit said:
Thanks for the helpful replies everyone. I checked everything you all suggested. Everything looks good except the clutch stack height. It's probably about .080 in. from being flush. This bike has a Norvil belt drive, and I see in their instructions where they suggest you add an additional plate, which apparently I don't have, and which is about that thickness. I just went ahead and ordered a new clutch pack from CNW. Hopefully, that will solve the problem.
Click to expand...
I really don't see how it would matter if it was a chain or belt in relation to clutch pull. Anyway, a fresh pack should resore pack height to spec. Being at .080, fresh stuff should add .030 to .040.
Click to expand...
Well, I think it's because the belt drive mod comes with its own clutch basket. It must be deeper than stock. Why, I don't know.
 
That's what I was thinking, the new belt drive clutch basket could be a different depth than the original. Might need a shim to bring the pack height up close to the spring. I'm not sure about the wear, that may be minimal, but I'm not the clutch expert, but after 13K on mine it works fine but could use a shim.

Dave
69S
 
Hey,

The Norvil clutch basket is in fact slightly deeper and designed to use an additional steel plate (1st one in). Then installing a full 850 stack (with the thinner 850 style pressure plate) will give you the right size stack. This will, compared to a std chain drive clutch, put your spring closer to its release and will therefore give you an easier clutch pull.

Matt / Colorado Norton Works
 
CNW said:
Hey,

The Norvil clutch basket is in fact slightly deeper and designed to use an additional steel plate (1st one in). Then installing a full 850 stack (with the thinner 850 style pressure plate) will give you the right size stack. This will, compared to a std chain drive clutch, put your spring closer to its release and will therefore give you an easier clutch pull.

Matt / Colorado Norton Works
Click to expand...
Update: The Barnett clutch plates (plus one additional plain plate) arrived from CNW. Installing them brought the clutch pack height up perfectly flush with the bottom of the snap ring grove. The result is like a new bike! I can actually pull the clutch with one finger, but not only that, the engagement is much smoother than before. The clutch actually has feel now.

Life is good. . . that is until I read Matt's comment. . . Matt, you said the extra steel plate should be the first one in the pack. I didn't do this, rather I started with an internally splined friction plate and alternated the stack as per the manual for a regular clutch stack (doah!). Now that I think about it, it kind of makes sense, but what difference does it really make? Should I do it over?
 
Glad you got it sorted and reported back. It's nice when things work out and a fix is available.

Thanks,
Dave
69S
 
Status
Not open for further replies.
Back
Top