Also, and I'd forgotten this, I had to cut it out of the motor because the front mounting bolt was completely frozen into the tube from riding in winter salt, so I had the joy of getting that out.
I rebuilt it back in 2011. It was the first motor I ever rebuilt, and it almost caused me to swear off working on scooters. It probably took me thirty hours to tear it down between having to learn every step of the way and not having any vespa-specific tools other than a flywheel puller.
The only performance upgrade I did was to put a 2-port Pinasco 177 on it. Tame, but decent torque.
I probably spent ten hours trying to get the rear hub castle nut loose, for example, whereas this time with the correct castle nut tool and my impact wrench, it took maybe thirty seconds.
So at this point, other than ordering new mounting buffers and the various other rebuild parts, I have a couple of actual engineering decisions to make.
First off is how much to even try and port this thing. The deck on the motor has almost NO room to expand, so if I do it, it's going to mean adding JBWeld and knowing I'll be cutting into that.
The more significant question is whether I can use the long stroke Mazzi crank I originally bought for my Sprint before switching it for one with a P-series flywheel taper. On the clutch side, though, the sprint crank has the bearing outside the seal.
Is it possible to swap the bearing/seal order to use the Sprint crank?
Either way, interestingly, the prior crank has already been cut to the same timings as the Mazzi (138°/6°).
Finally, I'll go for port timings of 124/172/26, same as my Sprint, assuming I can pull it off. The old port timings were 122/152/14, so the exhaust needs some serious work, but the transfers just need to lose the .25mm base gasket and I'm at like 123.3 on the transfers. The exhaust is going to need to be raised a good five mm to get to 172.
I'm going to aim for peak power at 7,000 RPM's since the 2mm rings will float at 8,000. I need to spend some time working out the intake milling and timing for that, still.
So lots going on, hopefully good
I now include a dog in as many pictures and videos as possible.
I made it look like this
The gasket is an exact match to the meat on the case ::
Dunno this crank brand. DE-MI?
Cut n' Color...I mean fill...
There's actually a gate over the port on the right (bottom) side of the transfers, so this would open that up.
Last edited by chandlerman on Mon Jan 04, 2021 6:20 am; edited 12 times in total