Modern Vespa

Not knowing the condition of the motor of my 1965 VBB barn find the only solution was to rebuild it so that I could put at ease any concern I had about bearings, seals, "O"rings, etc.
I learned as I went. Replaced the following:
The Cruciform gear selector,
The rear wheel seal,
Kick Starter seal, gear, spring and pads,
Springs within the cush drive and new needle bearings,
New main seals on fly side and clutch side,
New crank bearings on both fly side and clutch side,
New piston, wrist pin and clips,
New cylinder,
New head, and plug,
New clutch plates and basket,
New rear brakes, castle nut and clip,
New stator, points and condenser,
New Coil,
Needless to say new gaskets all the way around,
I did not replace the main mounting rubbers as they appeared to fine.
Actually the main bearings looked great too but while it was apart I
replaced everything. I'm still running the original crank and rod. All transmission gears and gear tree looked like new. No wear could be found. Original machining marks was still visible.
After the rebuild I rode the bike for a season then tore it apart to start the body restoration. After completion of it for some unknow reason the darn thing just wouldn't start. It was then that I decided to convert it to a 12V CDI system. That solved all the starting problems and added all the fringes that a 12V system allows such as better starting, hotter spark, brighter lights.

Good work! Welcome the endless process of learning that is old motorcycle ownership.

Did you pitch the old stator? If not I'd recommend hanging on to it. If you don't want it I'll take it.

That rear hub just needs a little brake parts cleaner and it'll be fine!

More Photos of this rebuild.
I have many more photos of this undertaking. I sort of revised it down for posting purposes.
After the engine rebuild it performed great during the last riding season. The bike starts on the 2nd or 3rd kick and never misses a beat. I am now quit sure this motor will last for many more years. Were there anything really bad in there? Well mostly no. But then there were issues that needed to be seen to such as there was no seal at the kick starter shaft. The kick starter bumpers were in bad shape. The original clutch was a shambles and of course there was the bad rear seal which could have been done without splitting the case. Not mention I wanted to go to a dome piston. The bearings were good but replace just the same. The seals were old, stiff and brittle and needed replaced. The cruciform also showed wear and was replace. So yes, it was a job that indeed needed done.

Nice looking work! This is clearly not your first rebuild.

Also, I couldn't help but notice this alignment of caption to the background of your next image...

What a fantastic posting. The re-build was meticulous and well done. The photographic documentation is superb. I followed your re-build and restoration and was very impressed with your work. The final outcome was a complete success. I have ridden this restored 1965 VBB and it rides and performs flawlessly. It is a joy to behold (including the body restoration and painting). Congratulations on a splendid job.

Great job - I have nothing to compare it to but isn't 100 PSI on the compression a little low ? The only reason I ask is. I recently checked the compression on my old un-rebuilt motor and found it to be 90 PSI. I thought the range of 120 PSI Is what we were looking for. Maybe once everything is seated it will change. I have no experience in this area.

I assume your bike is the one in your Avatar? where is your seat from? thanks.

Yes, the restoration I have outlined here is of the bike pictured in my Avatar. The seat pictured is from Scootermercato as were most parts used in the rebuild.
In regards to the compression number. Personally I view that number a moving target so to speak. When fitting the top end the first time I was very accurate in fitting the piston to cylinder and the ring gaps. They were done by the book 100%. However as I mentioned earlier I was having soft seize problems. At about the 6 mile out range it would soft seize 90% of the time. Needless to say I couldn't have that so the top end was torn down and both the piston to cylinder and ring gaps were relaxed a tad after which it has never seized again. I did not take a compression test before that adjustment so I can't post any numbers for it when set by the book specs.
Bottom line, I don't really know what a healthy '65 VBB 150's compression should be nor do I care. All I know is that this one runs beautifully and I wouldn't change a thing just to get obtain a number. It does have less than 500 miles on the rebuild so it is possible that the compression number may go up a little as it seats.
BTW, my brother has a 1963 Allstate 125 converted to a 150. His bike runs as good as mine and I believe his compression is in the 70's.

Chandlerman - you beat me to it.

Mickeyfan - Great pics and some really sweet details. Also - the motor pics were great too.

:-)

Seriously - awesome job - and thanks for all the tips and tricks.

nice work.