MZ/MuZ Riders

Now I've sorted this before on different bikes by getting the engine warm, putting the front wheel against a brick wall , pulling in the clutch and selecting first gear. This has previously resulted in a loud bang and a free clutch. It's never failed to work. However, I'm now (a lot) older and concerned that I may do some damage.
I guess I'm (hopefully) looking at a stalled engine if it doesn't free off or at worst it could result in mechanical damage.

Anyone freed off a clutch successfully on their 660? Anyone have a tale of trying and breaking something? I'm just trying to weigh up my options and convince myself to either give it a go or take it apart.

Maybe you know a better, less potentially destructive method? Anyone?

Before starting a big single or an older British motorcycle I pull in the clutch, shift to a higher gear and rock the bike back and forth with the clutch lever pulled till it frees up.
OMC

do be careful with the mz 125cc 4 strokes
you can take out the starter sprag clutch
if you push the bike backwards and the starter turns via the whole drive line

i was going up hill on wet grass and lost power and the engine died
i let out the clutch to stop bike and me from going down the hill backwards
as i could not get my foot on rear brake
BANG went the sprag
dave

Bad idea to bang it into gear with the clutch stuck.
It will take teeth off the trans. gears or round off the dogs guaranteed. i can post some ugly gear pix if you doubt it.
I have heard of cracking cases from this too.
The following unsticking recommendation assumes a properly adjusted clutch release:
If it won't rock free as previously posted, start it up, get it rolling , pull the clutch, and slip into first or second gear, and
while holding the clutch in buzz it and ride the rear brake.should break loose .
This can alternatively be done on a center stand , best getting the wheel spinning first.Having it in higher gears will work best.
Oftentimes , a mildly stuck clutch will free up by just pulling the clutch in and revving a couple times before attempting
engagement.
Some bikes (Brits esp.) stick bad while parked for a few days. Kludge remedy is to velcro strap the clutch lever to the bar
when the bike is parked for extended periods. This has been the magic cure for my Bud's '70s Bonnieville.
I am also assuming that your clutch works OK after breaking loose and warming up. If not , you have warped plates
or worn basket/hub. This will be manifested by dragging and hard shifting.
Good luck,
Jim

Unless the plates are warped, the wet clutch in the various versions of the Yamaha motor does not stick in the classical sense. I personally have never had warped plates in this engine.
It is just the "stickiness" of the cold oil dragging. After a few meters it will be fine and shifting into first after starting, altho it does jolt, does no damage.
the fainthearted can, as advised, put it in gear, pull the clutch and jostle back and forth a few times before starting. It will jolt anyway, perhaps not quite as badly.
Old brits have essentially dry clutches which sorta gets oily a bit ( if the oil level in the primary chain case is correct) and cork lines plates. These cork pads really do stick to the neighbor plate after a while.
Some "high-performance" engines from back then, mostly italians taken more or less from the circuit, have metal-metal (i.e.copper-steel) wet clutches which 13 and more plates and these either do not separate at all when cold or slip all the time, depending on the adjustment. Back then, one was in the habit for racers of heating the crankcase with a blowtorch or charcoal fire underneath, before starting the engine and even then thinner oil was in the thing until it was warm, the warming up done in the paddock, then the heavier Castrol 50 or 60 oil went in along with colder plugs and possibly with two strokes other jets. The clutch was fine once hot.

So is the XTZ clutch. there is no cure because it is not an ailment.
Using highest quality 10W50 synthetic oil does help a lot. cheap oils are much grabbier, not to mention what other damage they can cause.

I would concur with Bill, they will jolt a bit but I have found that if you are riding everyday this is not an issue. Let them sit for a week or more and you'll get a jolt, ride it everyday - no worries at all.

Just my 2p worth

Do not use "Energy Saving" oil. This will cause the plates to stick.

JK

what is energy saving oil?

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The old brits with their semi-dry clutches and separate gearboxes don't care but for more modern engine with wet clutches like ours, one should definitely not use service station oil for cars etc.
There are technical reasons for motorcycle oils based on the wet clutch, the fact that the cluster uses the same oil and also the many ballbearings. Especially the "grinding" action of the gear teeth breaks down car oil rapidly
They are more expensive for good reasons and not to rake in the dough.
That said I did try several different racing oils for cars in the racing engine without slipping clutch.
Silkolene 0W/40, AGIP and Motul 0W/40, Castrol OW/50...
Oil gets changed so often in competition motors that the degradation mentioned above is not a serious issue.

on North American oil containers, the API Service label indicates if an oil is a heavy duty type or "energy conserving"
Most of the car "energy" or "resource conserving" oils have anti friction additive packages which are not ideal for wet clutches.
Although I'd think this might alleviate clutch sticking !

Well I finally got round to trying this after sorting other stuff on the bike and there was no loud bang just a quiet "snick" as the plates released.
Now however I've got to buy a new waterpump/waterpump housing as both inlet and outlet (I presume that's what they are) are cracked. As soon as that's on it's MOT time.
On the plus side the engine starts easily, sounds quiet internally. It doesn't get too hot just standing ticking over without a fan. The noise from the Werkes exhaust however sounds very fruity but I may have to pack it before the MOT.

Bill Jurgenson wrote:what is energy saving oil?

What they call "friction modifiers" in the additive package - the stuff that messes up wet clutches.
Any motor oil that is H or J or M - anything after G. (I forget what the standard is, SAE or what.)

Bill Jurgenson wrote:That said I did try several different racing oils for cars in the racing engine without slipping clutch.
Silkolene 0W/40, AGIP and Motul 0W/40, Castrol OW/50...

Interesting - all 0W. I don't know what Motul has now that is 0W; I've only seen 10W.