Modern Vespa

Greetings,

I decided to finally get my P200 back on the road. It has been sitting since 2018 as I've been busy w/ VW projects. I took it to a local mechanic and so far the crank is bad. (stock engine minus I believe the the sip road exhaust). The P/C are yet to be evaluated.

I only want to be able to run around town and maybe the occasional rally or even a trip to the beach(80miles - from Portland Or. ) Reliability is top concern, performance and mpg would be secondary.

I don't want to spend the big $$ on it but looking like a rebuild is in order. What would you guys recommend? TIA!

Tony

What did your mechanic recommend?

Hi Tony, I've rode many different routes from PDX to the beach. There's always hills and headwinds to contend with. My go-to engine builds have always been stock 200, 24/24 carb, short 4th gear, and a box exhaust (i still use a Sito+). I'll match the flow of the carb to the carb box and to the engine case, but no additional porting. Like it really doesn't get anymore reliable that that combo. And i'm REALLY going to push you towards installing that short 36t short 4th.

As for cranks, i'm not a fan of Mazzy or BGM. SIP makes a VERY nice 60mm long stroke crank that has similar inlet timings as stock. https://www.sip-scootershop.com/en/product/long-stroke-crankshaft-sip-performance_45021600?usrc=Racing%20Crankshafts%20-%20Disc%20Valve

I will definitely be taking his recommendations highly. He has only spent a few minutes to see that the crank was bad and to see if I wanted to go any further.

The next step is to open it up and check the rest to see how far we must go.

Thanks form your reply! The suggestions you make sound like what I'm looking for. Simple and reliable. I'm not commuting or racing, but want to enjoy the ride. And yes, we do have hills around here and out to great places to ride.

I've been reading and researching a bit and it seems many people are very happy with the short 36 tooth 4th. I don't need high top speed so this seems like a good way to go.

With a 60mm crank, are there other modifications that need to happen? (57mm is stock, yes)

Cheers,

You'll have to install a packer (spacer) either in between the case and the bottom of cylinder, or between the top of the cylinder and the head. The only reason i mentioned a 60mm crank is because i don't know who makes a quality stock 57mm crankshaft. And yes, a 57mm crank would be more simple than a 60mm.

And FYI, my top speeds have always been the highest (with my stock 200 engines) after i install a short 4th. So don't think for one second that you'll loose any top speed. Yes, the scooterhelp gearing calculator says different, but in real world conditions it's inaccurate.

Ok, that makes sense. I'm anxious to see what the rest of the engine looks like. I will report back! Appreciate your input!

And depending upon what portiion of your crank is damaged, there's a local guy who can rebuild them...

https://www.sip-scootershop.com/en/product/conrod-kit-mazzucchelli_BCO0502A?usrc=Cylinder%2C%20Piston

Right on! I'll keep that in mind. I like the idea of the 60mm crank, though and the short 4th. On the list.

More to follow.

I just thought I would update this build/project.

My mother has had some health issues and this was not a priority.

The case was bad and we could have 'adapted/converted" to reed valve, but I have found a good crankcase and the mechanic will rebuild for me. I'm going to stay stock and switch to a short 4th.

I appreciate everyones advice here. I am hoping to do a build to my 50 special as well pretty soon.

Cheers,

Tony