Modern Vespa

Hello
A bit of an exaggeration but I had the same problem a year ago. When i get hold of the flywheel it rocks up and down. There's play in the flywheel bearing. I rebuilt the engine with new bearings and seals a year ago.

The crankshaft is a year old. I had to buy a new one because a Transvestite welder ruined the old one getting the bearing off. The only reason I discovered the flywheel problem was when I removed it just now as I lost power to all my lights and indicators last night.

I found a broken wire in the alternator coil. It's a SIP Vape ignition and I have had other problems with it. I don't recommend them. My question is does play in the bearing matter? Do all P range engines do this?

This is all quite funny. It sounds like an episode of Benny Hill.

Is the flywheel rocking on the crankshaft (taper issue), or is the crankshaft rocking in the bearing?

This scooter is a disaster. I never had a single problem with my 1981 P200E.

Hello Mate. It's definitely the shaft in the bearing. The Taper is good, clean and torqued. I was to fit the DR top end as the 7500 mile service is about due when I have time.

How far does it rock up and down? I had maybe a 1/2 mm play up and down on a build I had back in the day. Brand new crank and bearings installed. You really had to work on wiggling it, but you could get a definite tapping sound out of it. Never had a problem with it but it scared me when I was looking at it.

Hello MJ.
It's a tiny amount of movement but it looks like a lot when looking at the top edge of the flywheel. I think the only course of action is when I'm next at a Rally is to go round wiggling Flywheels. I'm surprised I haven't received loads of replies from you all who went and tried moving your flywheels up and down just in case.

Whoops! Meant to say I had movement at the crank. Never had the flywheel attached when I was wiggling it.

If you pull the flywheel can you wiggle the crank enough to hear a light tapping in the bearing?

What's the inside of the flywheel cone look like? Rough inside there? Loose? Woodruff key smeared a bit?

Read here somewhere that you can test the bearing by pulling the clutch while holding the flywheel. Mine wiggles very slightly.
And that it isn't uncommon or dangerous.
Really going to make a point of not letting a transvestite welder pull my crank.

I vote for a dial gauge micrometer and checking for runout on both sides of the crankshaft while it is still in the bike.

While a new crank should be true, I have never seen on any of the parts sites guaranteeing it.

Tin foil hat version of events is your flywheel is unbalanced or was the taper is not centered/straight and it is bending cranks or chewing the bearing.