Modern Vespa

I'm in the midst of re-installing my motor in my frame.

My motor is now "in gear" so when I turn my brake drum / wheel, the crank turns as well. However, when I press on my clutch lever (red arrow) manually, my wheel / crank continue to be engaged.

I would have thought that they would disengage when the clutch lever is pressed. But maybe the motor should be running, oiled, upright - I don't know.

Are you pressing the lever far enough to disengage the clutch? Takes a bit of force and travel past where the initial contact is felt. You should also be able to move it through the gears into neutral as you turn the hub or using the kick pedal. With the plug out. Is the batwing on the neutral notch ? Should work upside down.

Thanks for your reply. The shifter box / batwing is not installed yet so I can access the shifting shaft. I can shift it into gear or neutral from there no problem.

I've taken this whole motor apart except for splitting the cases and removing the clutch cover. As they say, "it ran before I took it apart" so I'm hoping I don't have to do any more disassembly.

I am curious to know how you did that ?

I know you're kidding, but after "critically" inspecting the crank and rod with my caliper fingers and determining that it was ok, I said that was far enough.

Same principle...

There is always some friction in the clutch, the hub isn't going to freewheel like its in neutral.

Is the cylinder & spark plug installed (are you getting compression)? If so and it doesn't slip when you rotate the hub, then something is binding in the clutch, or plunger wasn't installed, or the pressure plate isn't in there. Sometimes its easy to forget to put some of those bits in, especially after a few beers and working on it with your mates.

Otherwise if there is no compression, the friction in there while disengaged could totally cause the crank to rotate, but it should slip if you fix the crank.

Actually, no, I wasn't kidding.....

And you did this without removing the head , right ?

So what I did was:

* Drop the motor
* Pull the head, cylinder and piston
* Pull the carb and related
* Pull the flywheel

I did not:

* Remove the clutch cover
* Split the case

I also did not bother with timing but I did mark TDC when I installed the piston.

OK then.

It's probably fine. It's hard to disengage the clutch by hand like that and there will be friction connecting the two. If you put a plug in then compression will push back on the top end and help it slip, or you can lock the top end down and try to give it a proper slip test, but unless you have a cause for concern now it'll be easy to test on the bike with the kickstart and clutch cable strung up. Not that hard to take it back off with the engine mounted

Thanks for this. Now is the time if there was something wrong which is why I was concerned.

And thanks everybody else for their helpful comments. I'm moving forward with assembly.

I suppose the question i'd ask is, has the engine been out of the frame for a long period?

If so, sticky clutch plates are going to happen, and you dont have the spinning forces to free the clutch plates without a kickstart or the motor running, it'll still engage.

Its a perfect time to service the clutch whilst out of the frame. Check the plates for wear and make sure the plates are straight.