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Greetings to all,
With the help of Bob and others on the forum I`ve got my Monza 250 just about ready for the road. To my surprise after putting it all back together I have a problem with my clutch cable.

I bought a rather rough 67 Monza 250 a few months ago. When first tried, the clutch lever & cable worked as they should. I rode the bike up and down my street five or six miles before I started to restore it, and it shifted just fine. I`ve since replaced the handle bars with new ones of similar profile. Also replaced the rusted levers with a set of vintage Tommaselli Matadors. The clutch cable was not replaced. Any work I`ve done was at the bar end of the cable. I never removed the engine side cover.

When I tried the new levers I couldn`t get the clutch to release, even using the full range of adjustment at the lever. Also the action was MUCH more stiff than before. When in neutral, the wheel, chain and sprockets turn freely. When placed in gear the clutch will not disengage. I figured the shape, size or geometry of the new levers required an adjustment at the other end of the cable.

Today I removed the side cover. Loosened the clutch cable clamp. Set the handle bar lever adjuster to fully "in" position. Then pulled the cable adjuster snug against the clutch arm and tightened it down.
I then turned the lever adjuster out several turns till I feel a good amount of tension. To my disappointment the clutch will still not disengage and the effort to pull the lever in against the grip is extreme, too stiff to operate even if the clutch did disengage ! With the side cover still removed I can see the clutch arm work in and out. It seems to move through the full range of motion
I checked the cable for binding and it slides freely with no hard bends in its routing.
I can`t understand why just changing the bars and levers would cause a problem while it worked fine before ??
Any ideas are most apreciated.
Cheers,
Rick

Hello Rick,
One thing that my singles do is the clutch will not disengage easily when they have sat for a while.
So I pull in the clutch and kick them slowly until the clutch plates free up and disengages. Then the clutch works fine.
They are wide case 450s. Not narrow case, so maybe they're the same?

The stiff hard pull sounds like the cable is routed so it's hard to pull.
Try routing it so it has the least bends as possible to test.
Or maybe the new levers don't have enough leverage?

Graeme

Thanks Greeme,
I have gone back and found some posts from 2010 on this issue. I have re routed the cable acording to Bob`s instructions in the old post.
I also figure that some how my clutch release trouble requires adjustment of the clutch push rod on the left side of the engine. I`ve played with this for quite a while , trying various settings to achieve what looks like a max pull on the arm. I now have an easier pull at the lever but the clutch still will not release !
I did try to gently rock the bike in gear with the clutch pulled in. I also tried to slowly kick the motor with the gear engaged and the clutch lever pulled in in the hope that it may be stuck. All this to no avail.

Here are pics of the clutch arm at rest and pulled in fully.
Does this show a problem unknown to me ?

The odd thing is that the clutch worked just fine a few months ago. If I had never ridden the bike I would think perhaps some part of the clutch mechanism was missing or improperly installed.
I`m very frustrated as this is the only issue preventing me from trying out the Monza for the first extended ride.

" I have gone back and found some posts from 2010 on this issue. "

____ It may've been helpful if you had posted from THAT thread, (so we could then realize what-all you've now been brought up to speed on).
__ Anyhow,, I don't know if either of these are what you had found but, here are a couple related previous/past threads with posts concerning this associated topic-matter...
viewtopic.php?f=3&t=368&p=2424&hilit#p2424
viewtopic.php?f=3&t=369&p=2460#p2460


" I also figure that some how my clutch release trouble requires adjustment of the clutch push rod on the left side of the engine. I`ve played with this for quite a while , trying various settings to achieve what looks like a max pull on the arm. "

____ There is only one (best) setting for the clutch push-rod adjuster to be set at ! _ And that's so that the inner-cable's lever-arm is pushed outward as far as it can possibly go (with the eng.side-cover fully installed), without putting any pre-pressure against the clutch-springs.
__ This adjusting-process is best done with the right/rear eng.side-cover merely 'set' in it's normal place (but with none of it's screws installed),, that way, the job won't need to be redone-over again when afterwards it's possibly found that fully installing the cover then interferes with the lever-arm's newly set (& likely more outward) position.
So with the clutch adj.nut well loosened-outward, screw-in the clutch's threaded adj.rod until you see that the lever-arm has begun to push-out the eng.cover (outward & away from it's normal place against the motor-case). _ At THAT point (when the crack-line between the motor-case & eng.cover begins to widen & thus indicate separation is starting to occur between the two), the MAXIMUM lever-arm setting has then already been reached/surpassed ! _ Therefore you must next relax the adj.screw backward (so that the eng.cover can then once-again go-back into it's normal-place fully-back/tightly against the motor-case). _ So then next, try (lightly)- pressing the eng.cover back inward towards it's normal-position, and slowly relax -(loosen) the adj.screw until the eng.cover is then allowed to go-back to making full-contact against the motor-case. _ Now at this point, the lever-arm is merely in contact with the eng.cover (and the two are no-longer left causing interference with each-other). _ However even so,, (due to future clutch-plate wear), the lever-arm will require a little space (between where it & the eng.cover can come-into contact). _ So when relaxing the adj.screw outward,, then when the eng.cover has become fully flush with the motor-case, continue unscrewing it about an extra 1/2-turn (at least, but not much further than a whole turn), before next tightening-down the adj.screw-nut.
At this point, the clutch-adjuster lock-nut should then be fully tightened-down (without letting it's adj.screw turn any at all), and THEN the clutch-rod adjustment has been set OPTIMALLY (for best lever-arm leverage-action) !
__ Any extreme setting outside of this lever-arm's optimum-position, would then press it's (directly associated)- pushrod-pin somewhat-slightly FURTHER upward or downward (which is UNDESIRABLE), to a greater degree than necessary (while the lever-arm is only INTENDED to press INWARD) ! _ (Ya-see, since the lever-arm's pivot-point forces the arm to move in an 'arc', it must thus-then [unfortunately also] press the rod-pin upward & downward, [along with the DESIRED inward movement],, so you ought want to SET the lever-arm for minimum up & down pressure-advantage.)
When the lever-arm's position is set "optimally", then less effort gets wasted on forcing the lever-arm to press it's rod-pin (unnecessarily further) towards one of the undesirable directions (other than inward), which of-course the rod-pin obviously must refuse to move towards, (given it's restricted fitted-location) !
So-thus conversely, whenever the lever-arm has been (poorly) set to one of it's extreme settings, it then takes additional pressure to press the rod-pin inward.
So-therefore it pays-off to make sure that the lever-arm is set as optimally as it can possibly be, (which would then have the rod-pin being pressed 100% DIRECTLY INWARD [only], when the lever-arm is pulled-in HALF-way through it's working-arc !).
__ BTW, this clutch-rod adjustment-process should be done with the clutch-cable disconnected from the hand-lever,, and for best results, any excess inner-cable length should be cut-off (after all clutch & clutch-cable adjustment-work has been completed).



" I now have an easier pull at the lever but the clutch still will not release ! "

____ Do I understand you to mean that when you have the hand-lever pulled-back all the way to the handlebar-grip, the clutch-plates STILL remain fully engaged ? _ (Or perhaps you may mean that the clutch-springs are not pushing the hand-lever back into the released-position ?)


" I also tried to slowly kick the motor with the gear engaged and the clutch lever pulled in in the hope that it may be stuck. "

____ If you're meaning that the clutch-plates have become locked-up/adhered-seized together, then try placing it in neutral and push the Duke with the hand-lever pulled-in, then drop the shift-lever into 1st.gear, (with the ign.key off, of-course). _ The resulting compression-braking should brake-loose the stuck plates.


" Here are pics of the clutch arm at rest and pulled in fully. "

____ The first-thing I notice is that you have a front brake-cable terminal-clamp (on your inner clutch-cable), with it's bolt-head busted-off.
While that type of cable-clamp isn't the cause of your issue, you'll probably need to install a new clutch-cable (to get things set right).
__ Concerning your pic showing the lever-arm in it's fully pulled-in position... it's obvious that it's been adjusted to one of the extremes I've warned of !
In THIS case, it's been set so that the lever-arm is pressing DOWNward on the rod-pin too much (as the rod-pin is also pushed inward) !
With the lever-arm's angle set so far inward like that, you thus-then have two separate (but somewhat combined) pressure-issues to overcome...
First, the lever-arm's concave-receptacle is being forced to push the rod-pin downward,, and second, the inner-cable is forced to pull upward, (not just inward, as is desired), on the lever-arm.
Both of these (UNDESIRED!) actions are definitely wasting exerted hand-pressure at the hand-lever, (not to mention being extra-hard on those three engaged parts) !
So you need to re-set the relationship of the cable to the lever-arm, (and that won't be very easy with your busted terminal-clamp) !
__ Does your clutch-cable happen to be much longer than it really needs to be (by several inches) ? _ If so, (then with a new terminal-clamp), you could then cut-down the outer-cable's length a bit, so that the desired relationship could then be obtained, (in the manor I've already directed [up-above] ).


Hopeful-Cheers,
DCT-Bob

Sharp of you to noticed the bolt head busted off the adjuster. This just happened today as I tried to adjust and re-adjust the cable. I have since cut off the busted clamp and replaced it with another.
Before tightening the new clamp, I have followed your instructions for optimal adjustment of the clutch lever arm. I have set the arm as instructed to the point of contacting and pushing the case outward, then turned in one half turn. I have then tightened the clutch rod lock nut and also drawn tight and tightened the cable clamp against the arm. This setting is further outward than I had previously set. Therefore the clutch arm pulls in less close to the engine than I had set before. I had (wrongly) figured if the clutch would not release then perhaps it was not being pulled inward enough. Now set as you instruct, the pull force is much lighter and the action is nice and smooth. I had set the handle bar lever adjustment fully in and then turned it out a turn or two to put a little tension on the cable.

My problem is that the clutch STILL will not release !! When I place the bike in first gear, then pull in the clutch lever fully against the handle bar.... nothing happens. That is the bike remains in gear and can not be moved forward.
I`ve had cars that sat for extended periods have the clutch plate lock to the flywheel. Although the bike has only sat for two months, I had thought a similar situation may have happened to the Monza. This is why I tried the rocking and kicking while in gear. I have only used gentle action thus far and had no success.
I `ll try to be a little more agressive with the pushing in neutral then dropping into first and see if that frees thing up.

Will report back shortly.

It should release with a bit more effort.
I assume narrow case engines have the clutch inspection cover to see the clutch is actually moving when you squeeze the clutch lever?
If my 450 doesn't have it's clutch freed by kicking it through with the clutch pulled in untill the kick lever is free, it will stall as soon as it is put into gear, just like the clutch wasn't pulled in.

I just pushed it down the driveway several times. I roll it in nuetral at a pretty good pace with the lever pulled in, then drop it into first gear. It will not roll free. Instead it turns the engine over against the compression even as I hold the lever fully against the handle bar.
When I look into the clutch window on the left side I can see the clutch plates move in and out when I pull at the lever. However I can not get the clutch release at all !

Sometimes the stack of clutch plates can really stick together, when unused for a long time.
If you are the careful type, you could remove the clutch cover to gain access to the clutch, and use a screwdriver to prise the plates apart with the clutch handlebar lever pulled in.
A quicker if riskier way is to run the engine in neutral, place foot on rear brake pedal and with clutch lever pulled in, put into first gear. I've done that and survived, but it's nerve-racking and there's no guarantee the gears won't be damaged!

Jordan

" I have set the arm as instructed to the point of contacting and pushing the case outward, then turned in one half turn. "

____ It seems you've understood that the clutch push-rod adjuster-screw must be 'set' inward as far as possible without causing the lever-arm to be pressed against the shifter-box/eng.cover -(not "the case"),, and that once contact has become obvious, the screw-adjuster should then be backed-off a little (so as to make-sure the lever-arm does-not remain bottomed-out against the eng.cover).
__ I hope you also realized that it's possible for the inner-cable & it's clamp to also interfere against the inside of the eng.cover (and thus possibly prevent the lever-arm from fully releasing it's pressure against the rod-pin).
Cuz if any such undesired pressure remains against the rod-pin, then it could possibly lead to some clutch-slippage.
You can tell if there's any such interference, because the shift-box/eng.cover will then not stay-put completely in-place up-against the motor-case, (when all cover-screws are removed).
So before the cover-screws are installed, ya should double-check your clearance work, by trying pulling-in the hand-lever and let it pop-back-out, so as to make-sure that the eng.cover doesn't then get bumped-outward from it's normal-place.
If then the eng.cover does get moved-away from it's place, it could simply be due to light-pressure merely from just leftover/excess inner-cable (which ought to be cut-off). _ However if the pressure (against the eng.cover) seems strong enough to be produced by the clutch-springs, then ya know that the clutch adj.screw has the lever-arm pressed too far outward (& against the cover).


" This setting is further outward than I had previously set. Therefore the clutch arm pulls in less close to the engine than I had set before. "

____ That's better and also as intended, now,, cuz before, you had the lever-arm set too far inward to take optimum-advantage of the peak fulcrum-point.


" Now set as you instruct, the pull force is much lighter and the action is nice and smooth. "

____ That's because not only are you now taking optimum advantage of the peak/center of the fulcrum-point's arc, you're no-longer having to waste a great portion of hand-lever effort towards forcing the lever-arm to press the rod-pin in a direction which it can-not go, and also, the inner-cable now pulls the lever-arm's tip-end in a direction which it is (much morely so) able to move towards, (instead of also towards a direction which it can-not move towards*) !
(* If you look-closely at your pic showing the lever-arm fully drawn-inward, it's obvious that the inner-cable is (undesirably!) trying to pull the lever-arm UPward [whilst also (desirably) pulling it inward], which wastes a fair-portion of hand-lever effort.)



" My problem is that the clutch STILL will not release !!
This is why I tried the rocking and kicking while in gear. "

____ It seems your clutch-plates have become stuck together.
__ While rocking the rear-wheel back & fourth with the hand-lever pulled-in while the transmission is engaged in 1st-gear, may help break-loose the stuck plates,, it's not so helpful to try using the kick-lever with the motor left "in gear". ...
The kick-lever turns-over the engine THROUGH the clutch,, so when the hand-lever is pulled-in, the kick-lever SHOULD then 'slip' as the clutch should also then be (normally) disengaged.
But with the motor put 'in gear', the kick-lever will then also try to turn the rear-wheel (regardless of the hand-lever's position), so that's of no added help !
__ So if the plates are not stuck-together very hard, then trying to kick-over the engine with the hand-lever pulled-in (while in neutral, [not 'in gear'] ), could possibly break-loose the stuck plates.


" I `ll try to be a little more agressive with the pushing in neutral then dropping into first and see if that frees thing up. "

____ While that process is more aggressive than trying the (above mentioned) kick-lever method, you could instead try push-starting your Duke by pushing it in neutral and then dropping the shift-lever into 1st.gear,, and then ride it for a while in 1st.gear while wacking the throttle open & shut, over & over with the hand-lever pulled-in,, until the warmed-up clutch finally brakes-loose.
THAT process always works (eventually) on a clutch which is stuck merely due to oil-adhesion between it's plates !



" I roll it in nuetral at a pretty good pace with the lever pulled in, then drop it into first gear. It will not roll free. Instead it turns the engine over against the compression even as I hold the lever fully against the handle bar. "

____ It seems your plates are REALLY stuck-together fairly hard for having been in normal-condition just a couple months back.
__ When was the last time the motor-oil was changed ?


" When I look into the clutch window on the left side I can see the clutch plates move in and out when I pull at the lever. However I can not get the clutch release at all ! "

____ Well that observation is certainly normal.
__ To get your clutch-plates freed-up,, you could try starting the engine in neutral, then while the motor idles, drop it into 1st.gear. _ It should then either lurch-forward a bit & stall, or, break-loose the plates.
If several attempts at this (at even higher idle) doesn't do it, then you'll have to take your Duke for a ride (left in 1st.gear) to get the clutch warmed-up & freed-loose, (as I've already mentioned above).


Hopeful-Cheers,
DCT-Bob

Thanks Bob, I`ll try and break the plates free with the engine running as you suggest. As for the oil change, I checked the oil level when I purchased the bike then ran it a few miles prior to taking it apart. I have no idea how old that oil was. I changed the oil recently and have only ran the engine maybe 15 minutes or so since. I haven`t ridden with the fresh oil due to this clutch issue.