LeMans III Clutch Issue

[MarkPell]

Hi All,

The clutch on my LeMans won't disengage. It was very grabby to begin with and was adjusted to engage with the lever almost completely out. I adjusted it even further with almost no adjustment left with no luck. I also recently changed the gear oil.
Is there anything else I can try before pulling the clutch assembly apart?

Thanks,
Mark

[fotoguzzi]

There's another adjustment point on the back of the transmission and a 3rd on the cable near your right foot.

[guzzisteve]

You could try flushing the bell housing w/mineral spirits.  Just plug the slot on bottom, use a funnel and fill through the inspection hole on R/H side. I used a wood wedge in the slot or an old piece of innertube. I made lot of extra money changing clutch hubs in the 80's, cause most every one was bad. Not the new parts so much till new hub came out on 93 models.

[MarkPell]

There's another adjustment point on the back of the transmission and a 3rd on the cable near your right foot.

Cable adjustments at both ends are pretty well maxed out. Considering it wasn't engaging until the lever was completely out, I would think it wasn't an adjustment issue to begin with, but I will try the 3rd one at the back of the tranny too.

[MarkPell]

You could try flushing the bell housing w/mineral spirits.  Just plug the slot on bottom, use a funnel and fill through the inspection hole on R/H side. I used a wood wedge in the slot or an old piece of innertube. I made lot of extra money changing clutch hubs in the 80's, cause most every one was bad. Not the new parts so much till new hub came out on 93 models.

Thanks Steve, I'll give that a shot. In the event I'm looking at a clutch hub issue, can it be removed with the engine in the frame?  Are there other improvements that could be done at the same time to increase clutch actuation and/or reduce the king kong pull needed to operate it?

[guzzisteve]

Engine stays if you crab the frame, updates are replace seals, gaskets & crush washers on the crankcase vent system, motor & trans while you have it apart. That's the short of it unless you seal up the cam plug on the back of the block. A good time to replace hoses to everything.  Research crabbing the frame. Oh, the fun of it.

[nyITguy]

Out of curiosity, I googled "crabbing frame," as I had no idea what that could mean. Found this great tutorial by Pete Roper and Rolf Johansen, maybe it saves someone some time:

http://www.thisoldtractor.com/guzzitech.dk/pdf/access-gearbox-clutch-big-twin-en-2004-07-04.pdf


Sent from my iPhone using Tapatalk

[pehayes]

How many miles on this machine?  The Guzzi double plate clutch is usually robust until nearing 100K miles.

Before you do all this big disassembly, make two inspections.

1-lay under the bike or place a mirror or use a friend.  Look at the action lever at the back of the transmission.  When you pull on the hand lever, does the transmission lever come in and abut any part of the transmission rear cover casting?  If so, adjust the pin in the center of the transmission lever to create some free space at full pull.

2-again under the bike.  Look at the relationship between the outer body of the throwout system and the rear cover casting around it.  At rest, the outer body should be just about flush.  If the outer body is substantially recessed into the casting it usually indicates some significant wear to throwout parts, usually the throwout radial bearing and race washers.  You should consider pulling and replacing the throwout bearing and race washers.  Easy to do with the swingarm off.  If the outer body is substantially exposed or proud of the surrounding casting it indicates wear to the clutch friction components themselves and then a full removal is in order.

Here is a pic of a recessed outer body.  Its a smallblock, but the parts and the visuals are pretty much the same.


Patrick Hayes
Fremont CA

[MarkPell]

How many miles on this machine?  The Guzzi double plate clutch is usually robust until nearing 100K miles.

Before you do all this big disassembly, make two inspections.

1-lay under the bike or place a mirror or use a friend.  Look at the action lever at the back of the transmission.  When you pull on the hand lever, does the transmission lever come in and abut any part of the transmission rear cover casting?  If so, adjust the pin in the center of the transmission lever to create some free space at full pull.

2-again under the bike.  Look at the relationship between the outer body of the throwout system and the rear cover casting around it.  At rest, the outer body should be just about flush.  If the outer body is substantially recessed into the casting it usually indicates some significant wear to throwout parts, usually the throwout radial bearing and race washers.  You should consider pulling and replacing the throwout bearing and race washers.  Easy to do with the swingarm off.  If the outer body is substantially exposed or proud of the surrounding casting it indicates wear to the clutch friction components themselves and then a full removal is in order.

Here is a pic of a recessed outer body.  Its a smallblock, but the parts and the visuals are pretty much the same.


Patrick Hayes
Fremont CA

Thanks Patrick.  There is only 17,000 miles on the bike so I am hoping your diagnosis is correct. I'll perform this inspection in the next day or so and follow up.

[pehayes]

Let me ask.  Have you been adjusting the clutch lever and cable so that it is taught?  Sure way to quickly disintegrate the throwout bearing.  That bearing is only intended for intermittent or momentary use and can't handle full-time load rotation.  Always adjust the clutch so that there is some freeplay in the system at rest to ensure that the bearing gets fully unloaded.

Patrick Hayes
Fremont CA

[Chuck in Indiana]

^^^^ that would be an easy fix. You can replace the throwout bearing without crabbing.

[MarkPell]

Let me ask.  Have you been adjusting the clutch lever and cable so that it is taught?  Sure way to quickly disintegrate the throwout bearing.  That bearing is only intended for intermittent or momentary use and can't handle full-time load rotation.  Always adjust the clutch so that there is some freeplay in the system at rest to ensure that the bearing gets fully unloaded.

Patrick Hayes
Fremont CA

I just bought the bike a couple of months ago and it was that tight to begin with. Have put about 500 miles since purchased but clutch was real grabby with engagement happening with lever all the way out.

[pete roper]

Sounds like a notchy input boss to me. Regardless of the mileage it's a 35 year old motorbike with an unknown service history, chances are it's been running in a shocking state of tune for a while at least. When were the carburettors last balanced accurately and what speed does it usually idle at? I'll bet London to a brick that the clutch hub and probably the flywheel are shot to shit.

Pete

[MarkPell]

Sounds like a notchy input boss to me. Regardless of the mileage it's a 35 year old motorbike with an unknown service history, chances are it's been running in a shocking state of tune for a while at least. When were the carburettors last balanced accurately and what speed does it usually idle at? I'll bet London to a brick that the clutch hub and probably the flywheel are shot to shit.

Pete

Bike starts right up and idles quite nice (around 900). Hiccups a bit at low rpms but pulls like a mule above 5,000. Had big bore kit done with cams and custom pipes done years ago.  It certainly needs some fine tuning but plugs are clean and it seems real happy pushing it in it's happy zone of 5000-7500 rpm.

[pete roper]

Bike starts right up and idles quite nice (around 900). Hiccups a bit at low rpms but pulls like a mule above 5,000. Had big bore kit done with cams and custom pipes done years ago.  It certainly needs some fine tuning but plugs are clean and it seems real happy pushing it in it's happy zone of 5000-7500 rpm.

900RPM is way too low and will contribute to clutch boss wear. The fact it's hiccuping would indicate the ignition timing is out. There a lots of 950 mid valve MkIII's out there with B10's or warmer cams, it should idle smoothly at about 1,000-1,100rpm. Any lower than that and the intermediate plate and friction plates will flog the bejasus out of the hub and flywheel when the clutch is pulled at a standstill. Poorly balanced carbs and improper ignition timing will exacerbate the issue. My guess is you'll need a new hub, (Go deep spline.) friction and intermediate plates, possibly a new flywheel and it definitely needs to be tuned properly.

Pete

[SED]

Mark,

My LMIII also had low miles (22,000) and a very grabby clutch so I'm thinking Pete is right.  (though I'd definitely try Pat Hayes's checks)  Mine was absolutely terrible to maneuver around city streets so I quit riding it.

The earlier clutches had shallow splines that wear quickly.  The splines in the plates wear into the hub in such a way to form a ramp that fights the settling of the plates when the pressure plate pinches them.  (I don't remember all the details, but I can post pictures when I get home.)  You will need a new deep-spline hub and matching clutch plates but it is a complete replacement.

Crabbing the frame is not hard and gives plenty of access but the bike is balanced on the crankcase so a good idea to secure it from falling over.

I may have posted a photo essay on here when I did mine, but the photos have probably been lost to the photophucket black hole.

Shawn

[Antietam Classic Cycle]

The shallow splines weren't the problem, at least not all of it. Guzzi went through a period in the '80s where the hub wasn't heat-treated properly. Must have been done at the local pizzeria...

[SED]

The shallow splines weren't the problem, at least not all of it. Guzzi went through a period in the '80s where the hub wasn't heat-treated properly. Must have been done at the local pizzeria...

That explains why it seems like there was no problem with the earlier bikes.

Here's some pictures that might get Mark thinking about checking it out.  A great time to lube the u-joints!

free ebay image hosting

[MarkPell]

Well I tried Pat's suggestion and the operation of clutch cable/lever arm look clean so I guess I am resigned to a major repair.
I am pretty mechanically inclined but am seriously reluctant to take on a job like this so probably load it up on the trailer and off to the dealer.

I have AJ's in Gill, MA and or Seacoast Motorsports in Derry, NH as my 2 options (any others I may be missing?).

Have only purchased items from these 2 dealers, no servicing, but Seacoast is much bigger and seems to get good reviews.

Any thoughts?

Thank you all for you input so far!!

[fotoguzzi]

I am pretty mechanically

Any thoughts?

 

You can do this yourself! I'm not much of a mechanic but have done several.. I'll loan you my clutch compression tool.

[Tom]

I have the same problem on my MKIII LeMans.  Is yours white?  '83?  When I was on Oahu, I'd had problems with the clutch after letting it sit for a period of time.  The higher humidity had the clutch plates sticking together.  Bump starting got them to break loose.  Seeing that you're posting from Mass., this might be a solution.  Had to send some shock vibes into the transmission or have someone hold the clutch lever in and go through the inspection hole on the trans. to pry them apart.  Shooting mineral spirits/kerosene in there while you doing this probably wouldn't hurt either.

[MarkPell]

The bike is red but it had been sitting for years prior to my recent purchase of it. I will take yours and Steve's advise and try
kerosene and prying method before resorting to more drastic measures.  Thanks again!

[fotoguzzi]

The bike is red but it had been sitting for years prior to my recent purchase of it. I will take yours and Steve's advise and try
kerosene and prying method before resorting to more drastic measures.  Thanks again!

Umm,, not kerosene! use mineral spirits.

[MarkPell]

10-4!

[Tom]

I'll take back my response on the kerosene.  That could be too slippery for the clutch.  I'd try to pry apart first and see if that works.  Possibility that you might have to drill a drain hole into your trans. case.  Trying the prying first.  Go easy you don't want to tear things up.

[pete roper]

I really don't think the *Easy* solutions will work on this one.

Pete

[guzzisteve]

My 84 LM3 got real bad at 15K mi, notched hub looked just like the pics from SED. My 86 Cal2 started at 25K mi, I swapped it at 37K. Had a sidecar so I could keep the brakes on better so I didn't launch.

[MarkPell]

My 84 LM3 got real bad at 15K mi, notched hub looked just like the pics from SED. My 86 Cal2 started at 25K mi, I swapped it at 37K. Had a sidecar so I could keep the brakes on better so I didn't launch.

What were the symptoms when you say it got real bad?

[Antietam Classic Cycle]

I'll take back my response on the kerosene.  That could be too slippery for the clutch.  I'd try to pry apart first and see if that works.  Possibility that you might have to drill a drain hole into your trans. case.  Trying the prying first.  Go easy you don't want to tear things up.

No extra drain hole needed - there's already one. What are you going to pry apart? The plates are inside the flywheel, and there's nothing external that prying on will do any good.

[MarkPell]

I am resigned to thinking the major repair is likely needed based on the history of these bikes,
Any idea of the total material cost of all the items shown on the pics assuming that's what is needed?